Lol, a change from flowers, birds and fungi! Caught this Asian Elephant at the Calgary Zoo having a dust bath a couple of days ago. I've just read some interesting information on the Calgary Zoo website, link below.

 

"Asian elephants differ from their African cousins in that they have smaller ears, a less sloped back, only one 'finger' on their trunk, and the hind foot has 4 nails (rather than 3). Many think that the difference exists in their tusks (which are actually modified incisor teeth), since female Asian elephants appear not to have tusks. This is not true as female Asian elephants have tiny tusks under their trunk called tushes. It is also a misconception that all males have tusks because only about 20% of bulls actually do. These males are colloquially known as 'tuskers'.

 

Asian elephants rank as one of the smartest animals in the world and are capable of self-recognition. They live in herds of all females and their offspring is led by an elderly female called the matriarch. The females are usually related because females never leave the group that they are born into. Males get a little too rowdy for their parents during their teenage years. These teenage years roughly coincide with ours (12-14) because elephants have a similar lifespan of about 70 years.

 

There is a long history of elephants being hunted by humanity for meat, ivory, and domestication. The ivory trade continues to decimate wild populations, while their habitat is being destroyed for agriculture. Because of these factors, elephants have already disappeared from much of their former range (such as China)."

 

www.calgaryzoo.org/index.php?option=com_content&task=...

Asian Elephant

Elephas maximus

 

Asian elephants are smaller than their African cousins, and Intelligent and sociable, they live together in family groups and are usually led by the oldest female. Their most distinctive feature is of course their long trunks which can be very powerful, but also very delicate when needed to forage for food.

 

They need to eat a lot and can spend two thirds of a day feeding. They eat grasses, tree bark, roots, leaves and the like.

 

Their ivory tusks help with digging, stripping bark from trees and fighting. Not all male Asian elephants have tusks! But both males and females can have tushes, which are incisor teeth that grow to just below the bottom lip.

 

An elephant’s ears are used to keep the animal cool as they radiate heat, and Asian elephants have smaller ears than African ones. Despite the fact that their trunks are sophisticated long noses, Asian elephants have a finger at the end enabling the elephant to handle small items. African elephants have two fingers at the end of their trunks.

 

Elephants spend almost 22 months pregnant with a calf. That’s the longest amount of time for any mammal! Female elephants (cows), give birth to one calf every two to four years.

The Southeast African cheetah (Acinonyx jubatus jubatus) is the nominate cheetah subspecies native to East and Southern Africa. The Southern African cheetah lives mainly in the lowland areas and deserts of the Kalahari, the savannahs of Okavango Delta, and the grasslands of the Transvaal region in South Africa. In Namibia, cheetahs are mostly found in farmlands.

 

The cheetah is a medium-sized cat. An adult male cheetah's total size can measure from 168 to 200 cm (66 to 79 in) and 162 to 213 cm (64 to 84 in) for females. Adult cheetahs are 70 to 90 cm (28 to 35 in) tall at the shoulder. Males are slightly taller than females and have slightly bigger heads with wider incisors and longer mandibles.

 

The cheetah has a bright yellow or sometimes a golden coat, and its fur is slightly thicker than that of other subspecies. The white underside is very distinct, especially on the neck and breast, and it has less spotting on its belly. The spots on the face are more pronounced, and as a whole its spots seem more dense than those of most other subspecies. The tear marks are notably thicker at the corners of the mouth, and almost all of them have distinct brown mustache markings. Like the Asiatic cheetah, it is known to have fur behind its tail and have both white and black tips at the end of its tail. However, the cheetah may also have only a black tip at the end of its tail.

The pygmy hippopotamus looks like a mini version of its larger relative, the hippopotamus The pygmy hippo has adaptations for spending time in the water but is much less aquatic than the hippo. Its nose and ears close underwater just like a hippo's do, but its head is rounder and narrower, its neck is proportionally longer, and its eyes are not on the top of its head. The pygmy hippo's feet are less webbed and its toes more free than those of the hippo, and its legs are longer than its huge cousin's. The pygmy hippo's teeth are also different: it only has one pair of incisors, while the hippo has two or three.

Sony DSC-S75; Carl Zeiss Vario Sonnar, 2/7-21

 

In questo palazzo del XVI secolo è stato scoperto di recente un affresco che riproduce la Stanza di Eliodoro di Raffaello Sanzio (Musei Vaticani). Quasi certamente è stato eseguito da Ugo da Carpi, noto incisore e artista della cerchia di Raffaello.

 

In this building dated XVI century, few years ago was discovered a fresco, copy of "Stanza di Eliodoro" of Raffaello Sanzio (in Vatican Museum), painted by Ugo da Carpi, an artist working with Raffaello.

 

I diritti delle mie immagini sono riservati. E' vietato qualsiasi uso, senza il mio preventivo consenso:

mattia.camellini@alice.it

Sagui

Callitrichinae (também chamada Hapalinae) é uma subfamília de Macacos do Novo Mundo, da família Cebidae. Popularmente, são conhecidos por saguis, soim ou sauim, apesar de que para o gênero Leontopithecus, é mais comum o termo mico-leão.

 

Sagui-de-tufos-pretos

 

Um sagui[1][2] (do tupi sauín), soim ou mico são as designações comuns dadas a várias espécies de pequenos macacos pertencentes à família Callitrichidae. A palavra sagui tem origem no tupi e sua pronúncia é feita observando-se o som da vogal "u".

 

Estes primatas são representados por várias espécies em território brasileiro. Todos os quais possuem o dedo polegar da mão muito curto e não oponível, as unhas em forma de garras, e dentes molares de fórmula 2/2. São espécies de pequeno porte e de cauda longa.

 

São os menores símios do mundo, estão dispersos por toda a América do Sul e vivem geralmente em bandos que se hospedam em árvores, como os esquilos. Travessos e ágeis, movem-se em saltos bruscos, emitindo guinchos e assobios que são ouvidos de longe.

 

The black-tufted marmoset (Callithrix penicillata), also known as Mico-estrela in Portuguese, is a species of New World monkey that lives primarily in the Neo-tropical gallery forests of the Brazilian Central Plateau. It ranges from Bahia to Paraná,[3] and as far inland as Goiás, between 14 and 25 degrees south of the equator. This marmoset typically resides in rainforests, living an arboreal life high in the trees, but below the canopy. They are only rarely spotted near the ground.

 

Physical description:

 

The black-tufted marmoset is characterized by black tufts of hair around their ears. It typically has some sparse white hairs on its face. It usually has a brown or black head and its limbs and upper body are gray, as well as its abdomen, while its rump and underside are usually black. Its tail is ringed with black and white and is not prehensile, but is used for balance. It does not have an opposable thumb and its nails tend to have a claw-like appearance. The black-tufted marmoset reaches a size of 19 to 22 cm and weighs up to 350 g.

 

Behavior:

 

Diurnal and arboreal, the black-tufted marmoset has a lifestyle very similar to other marmosets. It typically lives in family groups of 2 to 14. The groups usually consist of a reproductive couple and their offspring. Twins are very common among this species and the males, as well as juvenile offspring, often assist the female in the raising of the young.

 

Though the black-tufted marmoset lives in small family groups, it is believed that they share their food source, sap trees, with other marmoset groups. Scent marking does occur within these groups, but it is believed that the marking is to deter other species rather than other black-tufted marmoset groups, because other groups typically ignore these markings. They also appear to be migratory, often moving in relation to the wet or dry seasons, however, the extent of their migration is unknown.

 

Though communication between black-tufted marmosets has not been studied thoroughly, it is believed that it communicates through vocalizations. It has known predator-specific cries and appears to vocalize frequently outside of predator cries.

 

Food and predation:

 

The Black-tufted Marmoset diet consists primarily of tree sap which it gets by nibbling the bark with its long lower incisors. In periods of drought, it will also include fruit and insects in its diet. In periods of serious drought it has also been known to eat small arthropods, molluscs, bird eggs, baby birds and small vertebrates.

 

Large birds of prey are the greatest threat to the black-tufted marmoset, however, snakes and wild cats also pose a danger to them. Predator-specific vocalizations and visual scanning are its only anti-predation techniques.

 

Reproduction:

 

The black-tufted marmoset is monogamous and lives in family groups. It reproduces twice a year, producing 1 to 4 offspring, though most often just twins. Its gestation period is 150 days and offspring are weaned after 8 weeks. There is considerable parental investment by this species, with both parents, as well as older juveniles, helping to raise the young. The offspring are extremely dependent on their parents and though they are sexually mature at 18 months, they typically do not mate until much later, staying with their family group until they do.

 

Ecosystem roles and conservation status:

 

The black-tufted marmoset is a mutualist with many species of fruit trees because it distributes the seeds from the fruit it consumes throughout the forests. However, it is a parasite on other species of trees because it creates sores in trees in order to extract sap, while offering no apparent benefit to the trees. Though this marmoset is not a main food source to any specific species, it is a food source to a number of different species, specifically large birds of prey, wild cats, and snakes.

 

While there are no known negative effects of marmosets towards humans, it carries specific positive effects by being a highly valuable exotic pet. It is also used in zoo exhibits and scientific research.

 

The black-tufted marmoset is listed as having no special status on the IUCN Red List or the United States Endangered Species Act List. It is listed in Appendix II of CITES and is not currently considered an endangered or threatened species.

BIG5 Elephant. Jock Safari Lodge. Kruger National Park. South Africa. Dec/2020

 

Elephant

Elephants are large mammals of the family Elephantidae and the order Proboscidea. Three species are currently recognised: the African bush elephant (Loxodonta africana), the African forest elephant (L. cyclotis), and the Asian elephant (Elephas maximus). Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia. Elephantidae is the only surviving family of the order Proboscidea; other, now extinct, members of the order include deinotheres, gomphotheres, mammoths, and mastodons.

All elephants have several distinctive features, the most notable of which is a long trunk (also called a proboscis), used for many purposes, particularly breathing, lifting water, and grasping objects. Their incisors grow into tusks, which can serve as weapons and as tools for moving objects and digging. Elephants' large ear flaps help to control their body temperature. Their pillar-like legs can carry their great weight. African elephants have larger ears and concave backs while Asian elephants have smaller ears and convex or level backs.

Elephants are herbivorous and can be found in different habitats including savannahs, forests, deserts, and marshes. They prefer to stay near water. They are considered to be a keystone species due to their impact on their environments. Other animals tend to keep their distance from elephants while predators, such as lions, tigers, hyenas, and any wild dogs, usually target only young elephants (or "calves"). Elephants have a fission–fusion society in which multiple family groups come together to socialise. Females ("cows") tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups are led by an individual known as the matriarch, often the oldest cow.

Males ("bulls") leave their family groups when they reach puberty and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate and enter a state of increased testosterone and aggression known as musth, which helps them gain dominance and reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell, and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness and show empathyfor dying or dead individuals of their kind.

Source: Wikipedia

Elefante

Os elefantes são animais herbívoros, alimentando-se de ervas, gramíneas, frutas e folhas de árvores. Dado o seu tamanho, um elefante adulto pode ingerir entre 70 a 150 kg de alimentos por dia. As fêmeas vivem em manadas de 10 a 15 animais, lideradas por uma matriarca, compostas por várias reprodutoras e crias de variadas idades. O período de gestação das fêmeas é longo (20 a 22 meses), assim como o desenvolvimento do animal que leva anos a atingir a idade adulta. Os filhotes podem nascer com 90 kg. Os machos adolescentes tendem a viver em pequenos bandos e os machos adultos isolados, encontrando-se com as fêmeas apenas no período reprodutivo.

Devido ao seu porte, os elefantes têm poucos predadores. Exercem uma forte influência sobre as savanas, pois mantêm árvores e arbustos sob controle, permitindo que pastagens dominem o ambiente. Eles vivem cerca de 60 anos e morrem quando seus molares caem, impedindo que se alimentem de plantas.

Os elefantes-africanos são maiores que as variedades asiáticas e têm orelhas mais desenvolvidas, uma adaptação que permite libertar calor em condições de altas temperaturas. Outra diferença importante é a ausência de presas de marfim nas fêmeas dos elefantes asiáticos.

Durante a época de acasalamento, o aumento da produção de testosterona deixa os elefantes extremamente agressivos, fazendo-os atacar até humanos. Acidentes com elefantes utilizados em rituais geralmente são causados por esse motivo. Cerca de 400 humanos são mortos por elefantes a cada ano.

Elefante é o termo genérico e popular pelo qual são denominados os membros da família Elephantidae, um grupo de mamíferos proboscídeoselefantídeos, de grande porte, do qual há três espécies no mundo atual, duas africanas (Loxodonta sp.) e uma asiática (Elephas sp.). Há ainda os mamutes (Mammuthus sp.), hoje extintos. Até recentemente, acreditava-se que havia apenas duas espécies vivas de elefantes, o elefante-africano e o elefante-asiático, uma espécie menor. Entretanto, estudos recentes de DNA sugerem que havia, na verdade, duas espécies de elefante-africano: Loxodonta africana, da savana, e Loxodonta cyclotis, que vive nas florestas. Os elefantes são os maiores animais terrestres da actualidade, com a massa entre 4 a 6 toneladas e medindo em média quatro metros de altura, podem levantar até 10.000 kg. As suas características mais distintivas são as presas de marfim

Fonte: Wikipedia

  

Jock Safari Lodge

Located within 6, 000 ha of pristine bushveld, Jock Safari Lodge is an exclusive private concession, perfectly positioned in the southern part of the Kruger National Park, South Africa’s largest national park. The wildlife within this region have survived undisturbed without negative impact from mankind, encouraged to thrive. Jock Safari Lodge emerges where the Mitomeni and Biyamiti rivers flow as one – this natural unbroken landscape offers guests one of the best Big Five game viewing experiences in South Africa with its exclusive riverbed traversing rights. Steeped in history, Jock Safari Lodge was the first private concession granted within the Kruger National Park and is named after local legend, Jock of the Bushveld, the canine hero of Sir Percy FitzPatrick’s famous story of courage and loyalty that is set during South Africa’s first gold rush era. Relive one of South Africa’s cultural heritages through this wonderful story and view the original mementoes on display at the Main Lodge.

Source: jocksafarilodge.com/

Jock Safari Lodge

Localizado em 6.000 ha de savana intocada, o Jock Safari Lodge é uma concessão privada exclusiva, perfeitamente posicionada ao sul do Parque Nacional Kruger, o maior parque nacional da África do Sul. A vida selvagem nesta região sobreviveu sem ser perturbada, sem impacto negativo da humanidade, encorajada a prosperar. O Jock Safari Lodge surge onde os rios Mitomeni e Biyamiti fluem como um só - esta paisagem natural contínua oferece aos hóspedes uma das melhores experiências de observação do Big Five na África do Sul com seus direitos exclusivos de travessia do leito do rio. Repleto de história, Jock Safari Lodge foi a primeira concessão privada concedida dentro do Parque Nacional Kruger e leva o nome de uma lenda local, Jock of the Bushveld, o herói canino da famosa história de coragem e lealdade de Sir Percy FitzPatrick que se passa durante o primeiro era da corrida do ouro. Reviva uma das heranças culturais da África do Sul por meio desta história maravilhosa e veja as lembranças originais em exibição no Main Lodge.

Fonte: jocksafarilodge.com/ (tradução livre)

 

Yet again, another Wood Frog.

The low boardwalk (literally planks on the ground) near one of the ponds on the Chatham trails allowed a very low angle. The use of a long lens made that angle even lower, and F16 made for a nice sharp reflection. The sun shining through some light clouds, and the blue sky overhead was a bonus! - Morris County Environmental Education Center, The Great Swamp, Southern Blvd Entrance, Chatham, New Jersey

View On Black

 

This image is one of my most popular images

click on the following link to see a slideshow of Dah Professor's Top 100 Images

South Africa.

Kruger Park.

Game Drive in open jeep.

 

WATCH THE VIDEO

 

Body stripes are less numerous and broader than that of the Cape Mountain Zebra, whereas body stripes extend around the belly. Leg striping is less prominent. Measures 1.3 to 1.4 metres at the shoulder and weighs 300-320 Kg. They have rounded ears approximately 160-170 mm long. Front portion of mane forms a black tuft between the ears. Diet: Predominantly a grazer, feeding in areas with short grass. Zebra have a strong sensitive upper lip with which it gathers herbage by collecting the grass between the lip and the lower incisors before plucking the harvest.

www.krugerpark.co.za/africa_burchells_zebra.html

Elephants usually have 26 teeth: the incisors, known as the tusks, 12 deciduous premolars, and 12 molars. Unlike most mammals, which grow baby teeth and then replace them with a single permanent set of adult teeth, elephants have cycles of tooth rotation throughout their lives. The chewing teeth are replaced six times in a typical elephant's lifetime. Teeth are not replaced by new ones emerging from the jaws vertically as in most mammals. Instead, new teeth grow in at the back of the mouth and move forward to push out the old ones. The first chewing tooth on each side of the jaw falls out when the elephant is two to three years old. The second set of chewing teeth falls out when the elephant is four to six years old. The third set is lost at 9–15 years of age, and set four lasts until 18–28 years of age. The fifth set of teeth lasts until the elephant is in its early 40s. The sixth (and usually final) set must last the elephant the rest of its life. Old elephants try to clean their food from dust in order to protect their last teeth. The African elephant is facing the greatest crisis in decades. Reports of mass elephant killings in the media vividly illustrate the situation across many African elephant range States.

 

For any form of publication, please include the link to this page: www.grida.no/resources/2322

 

This photo has been graciously provided to be used in the GRID-Arendal resources library by: Peter Prokosch

The ring-tailed lemur (Lemur catta) is a medium- to larger-sized strepsirrhine (wet-nosed) primate, and the most internationally-recognized lemur species, owing to its long, black-and-white, ringed tail. It belongs to Lemuridae, one of five lemur families, and is the only member of the Lemur genus. Like all lemurs, it is endemic to the island of Madagascar, where it is endangered. Known locally in Malagasy as maky ([makʲ] ⓘ, spelled maki in French) or hira, it ranges from gallery forests to spiny scrub in the southern regions of the island. It is omnivorous, as well as the most adapted to living terrestrially of the extant lemurs.

 

The ring-tailed lemur is highly social, living in groups of up to 30 individuals. It is also a female-dominant species, a commonality among lemurs. To keep warm and reaffirm social bonds, groups will huddle together. Mutual grooming is another vital aspect of lemur socialization (as with all primates), reaffirming social and familial connections, while also helping rid each other of any potential insects. Ring-tailed lemurs are strictly diurnal, being active exclusively during daylight hours. Due to this lifestyle, they also sunbathe; the lemurs can be observed sitting upright on their tails, exposing their soft, white belly fur towards the sun. They will often also have their palms open and eyes gently closed. Like other lemurs, this species relies strongly on their sense of smell, and territorial marking, with scent glands, provides communication signals throughout a group’s home range. The glands are located near the eyes, as well as near the anus. The males perform a unique scent-marking behavior called spur-marking, and will participate in stink fights by dousing their tails with their pheromones and “wafting” it at opponents. Additionally, lemurs of both sexes will scent-mark trees, logs, rocks or other objects by simply rubbing their faces and bodies onto it, not unlike a domestic cat.

 

As one of the most vocal primates, the ring-tailed lemur uses numerous vocalizations, including calling for group cohesion and predator alarm calls. Experiments have shown that the ring-tailed lemur, despite the lack of a large brain (relative to simiiform primates), can organize sequences, understand basic arithmetic operations, and preferentially select tools based on functional qualities.

 

Despite adapting to and breeding easily under captive care (and being the most popular species of lemur in zoos worldwide, with more than 2,000 captive-raised individuals), the wild population of ring-tailed lemur is listed as endangered by the IUCN Red List, due to habitat destruction, local hunting for bushmeat and the exotic pet trade. As of early 2017, the population in the wild is believed to have crashed to as low as 2,000 individuals due to these reasons, making them far more critically endangered. Local Malagasy farmers and logging industries frequently make use of slash and burn deforestation techniques, with smoke being visible on the horizon on most days in Madagascar, in an effort to accommodate livestock and to cultivate larger fields of crops.

 

Etymology

Although the term "lemur" was first intended for slender lorises, it was soon limited to the endemic Malagasy primates, which have been known as "lemurs" ever since. The name derives from the Latin term lemures, which refers to specters or ghosts that were exorcised during the Lemuria festival of ancient Rome. According to Carl Linnaeus's own explanation, the name was selected because of the nocturnal activity and slow movements of the slender loris. Being familiar with the works of Virgil and Ovid and seeing an analogy that fit with his naming scheme, Linnaeus adapted the term "lemur" for these nocturnal primates. However, it has been commonly and falsely assumed that Linnaeus was referring to the ghost-like appearance, reflective eyes, and ghostly cries of lemurs. It has also been speculated that Linnaeus may also have known that some Malagasy people have held legends that lemurs are the souls of their ancestors, but this is unlikely given that the name was selected for slender lorises from India. The species name, catta, refers to the ring-tailed lemur's cat-like appearance. Its purring vocalization is similar to that of the domestic cat.

 

Following Linnaeus's species description, the common name "ring-tailed maucauco" was first penned in 1771 by Welsh naturalist Thomas Pennant, who made note of its characteristic long, banded tail. (The term "maucauco" was a very common term for lemurs at this time.) The now universal English name "ring-tailed lemur" was first used by George Shaw in his illustrated scientific publication covering the Leverian collection, which was published between 1792 and 1796.

 

Evolutionary history

All mammalian fossils from Madagascar come from recent times.[11] Thus, little is known about the evolution of the ring-tailed lemur, let alone the rest of the lemur clade, which comprises the entire endemic primate population of the island. However, chromosomal and molecular evidence suggest that lemurs are more closely related to each other than to other strepsirrhine primates. For this to have happened, it is thought that a very small ancestral population came to Madagascar via a single rafting event between 50 and 80 million years ago. Subsequent evolutionary radiation and speciation has created the diversity of Malagasy lemurs seen today.

 

According to analysis of amino acid sequences, the branching of the family Lemuridae has been dated to 26.1 ±3.3 mya while rRNA sequences of mtDNA place the split at 24.9 ±3.6 mya. The ruffed lemurs are the first genus to split away (most basal) in the family, a view that is further supported by analysis of DNA sequences and karyotypes. Additionally, Molecular data suggests a deep genetic divergence and sister group relationship between the true lemurs (Eulemur) and the other two genera: Lemur and Hapalemur.

 

The ring-tailed lemur is thought to share closer affinities to the bamboo lemurs of the genus Hapalemur than to the other two genera in its family. This has been supported by comparisons in communication, chromosomes, genetics, and several morphological traits, such as scent gland similarities. However, other data concerning immunology and other morphological traits fail to support this close relationship. For example, Hapalemur species have short snouts, while the ring-tailed lemur and the rest of Lemuridae have long snouts. However, differences in the relationship between the orbit (eye socket) and the muzzle suggest that the ring-tailed lemur and the true lemurs evolved their elongated faces independently.

 

The relationship between the ring-tailed lemur and bamboo lemurs is the least understood. Molecular analysis suggests that either the bamboo lemurs diverged from the ring-tailed lemur, making the group monophyletic and supporting the current two-genera taxonomy, or that the ring-tailed lemur is nested in with the bamboo lemurs, requiring Hapalemur simus to be split off into its own genus, Prolemur.

 

The karyotype of the ring-tailed lemur has 56 chromosomes, of which four are metacentric (arms of nearly equal length), four are submetacentric (arms of unequal length), and 46 are acrocentric (the short arm is hardly observable). The X chromosome is metacentric and the Y chromosome is acrocentric.

 

Taxonomic classification

Linnaeus first used the genus name Lemur to describe "Lemur tardigradus" (the red slender loris, now known as Loris tardigradus) in his 1754 catalog of the Museum of King Adolf Frederick. In 1758, his 10th edition of Systema Naturae listed the genus Lemur with three included species, only one of which is still considered to be a lemur while another is no longer considered to be a primate. These species include: Lemur tardigradus, Lemur catta (the ring-tailed lemur), and Lemur volans (the Philippine colugo, now known as Cynocephalus volans). In 1911, Oldfield Thomas made Lemur catta the type species for the genus, despite the term initially being used to describe lorises. On January 10, 1929, the International Commission on Zoological Nomenclature (ICZN) formalized this decision in its publication of Opinion 122.

 

The ring-tailed lemur shares many similarities with ruffed lemurs (genus Varecia) and true lemurs (genus Eulemur), and its skeleton is nearly indistinguishable from that of the true lemurs. Consequently, the three genera were once grouped together in the genus Lemur and more recently are sometimes referred to as subfamily Lemurinae (within family Lemuridae). However, ruffed lemurs were reassigned to the genus Varecia in 1962, and due to similarities between the ring-tailed lemur and the bamboo lemurs, particularly in regards to molecular evidence and scent glands similarities, the true lemurs were moved to the genus Eulemur by Yves Rumpler and Elwyn L. Simons (1988) as well as Colin Groves and Robert H. Eaglen (1988). In 1991, Ian Tattersall and Jeffrey H. Schwartz reviewed the evidence and came to a different conclusion, instead favoring to return the members of Eulemur and Varecia to the genus Lemur. However, this view was not widely accepted and the genus Lemur remained monotypic, containing only the ring-tailed lemur. Because the differences in molecular data are so minute between the ring-tailed lemur and both genera of bamboo lemurs, it has been suggested that all three genera be merged.

 

Because of the difficulty in discerning the relationships within family Lemuridae, not all authorities agree on the taxonomy, although the majority of the primatological community favors the current classification.

 

Taxonomy of family LemuridaePhylogeny of family Lemuridae

Family Lemuridae

Genus Lemur: the ring-tailed lemur

Genus Eulemur: brown lemurs

Genus Varecia: ruffed lemurs

Genus Hapalemur: lesser gentle or bamboo lemurs

Genus Prolemur: the greater bamboo lemur

Lemuridae

Varecia (ruffed lemurs)

Lemur (ring-tailed lemur)

Hapalemur (lesser bamboo lemurs)

Eulemur (true lemurs)

 

In 1996, researchers Steven Goodman and Olivier Langrand suggested that the ring-tailed lemur may demonstrate regional variations, particularly a high mountain population at Andringitra Massif that has a thicker coat, lighter coloration, and variations in its tail rings. In 2001, primatologist Colin Groves concluded that this does not represent a locally occurring subspecies. This decision was later supported by further fieldwork that showed that the differences fell within the normal range of variation for the species. The thicker coat was considered a local adaptation to extreme low temperatures in the region, and the fading of the fur was attributed to increased exposure to solar radiation. Additional genetic studies in 2000 further supported the conclusion that population did not vary significantly from the other ring-tailed lemur populations on the island.

 

Anatomy and physiology

The ring-tailed lemur is a strepsirrhine primate, with a protruding muzzle and a wet nose. Top is the skull.

The ring-tailed lemur is a relatively large lemur. Its average weight is 2.2 kilograms (4.9 lb). Its head–body length ranges between 39 and 46 cm (15 and 18 in), its tail length is 56 and 63 cm (22 and 25 in), and its total length is 95 and 110 cm (37 and 43 in). Other measurements include a hind foot length of 102 and 113 mm (4.0 and 4.4 in), ear length of 40 and 48 mm (1.6 and 1.9 in), and cranium length of 78 and 88 mm (3.1 and 3.5 in).

 

The species has a slender frame and narrow face, fox-like muzzle. The ring-tailed lemur's trademark—a long, bushy tail—is ringed in alternating black and white transverse bands, numbering 12 or 13 white rings and 13 or 14 black rings, and always ending in a black tip. The total number of rings nearly matches the approximate number of caudal vertebrae Its tail is longer than its body and is not prehensile. Instead, it is only used for balance, communication, and group cohesion.

 

The pelage (fur) is so dense that it can clog electric clippers. The ventral (chest) coat and throat are white or cream. The dorsal (back) coat varies from gray to rosy-brown, sometimes with a brown pygal patch around the tail region, where the fur grades to pale gray or grayish brown. The dorsal coloration is slightly darker around the neck and crown. The hair on the throat, cheeks, and ears is white or off-white and also less dense, allowing the dark skin underneath to show through. The muzzle is dark grayish and the nose is black, and the eyes are encompassed by black triangular patches. Facial vibrissae (whiskers) are developed and found above the lips (mystacal), on the cheeks (genal), and on the eyebrow (superciliary). Vibrissae are also found slightly above the wrist on the underside of the forearm. The ears are relatively large compared to other lemurs and are covered in hair, which has only small tufts if any. Although slight pattern variations in the facial region may be seen between individuals, there are no obvious differences between the sexes.

 

Unlike most diurnal primates, but like all strepsirrhine primates, the ring-tailed lemur has a tapetum lucidum, or reflective layer behind the retina of the eye, that enhances night vision. The tapetum is highly visible in this species because the pigmentation of the ocular fundus (back surface of the eye), which is present in—but varies between—all lemurs, is very spotty. The ring-tailed lemur also has a rudimentary foveal depression on the retina. Another shared characteristic with the other strepsirrhine primates is the rhinarium, a moist, naked, glandular nose supported by the upper jaw and protruding beyond the chin. The rhinarium continues down where it divides the upper lip. The upper lip is attached to the premaxilla, preventing the lip from protruding and thus requiring the lemur to lap water rather than using suction.

 

The skin of the ring-tailed lemur is dark gray or black in color, even in places where the fur is white. It is exposed on the nose, palms, soles, eyelids, lips, and genitalia. The skin is smooth, but the leathery texture of the hands and feet facilitate terrestrial movement. The anus, located at the joint of the tail, is covered when the tail is lowered. The area around the anus (circumanal area) and the perineum are covered in fur. In males, the scrotum lacks fur, is covered in small, horny spines, and the two sacs of the scrotum are divided. The penis is nearly cylindrical in shape and is covered in small spines, as well as having two pairs of larger spines on both sides. Males have a relatively small baculum (penis bone) compared to their size. The scrotum, penis, and prepuce are usually coated with a foul-smelling secretion. Females have a thick, elongated clitoris that protrudes from the labia of the vulva. The opening of the urethra is closer to the clitoris than the vagina, forming a "drip tip".

 

Females have two pairs of mammary glands (four nipples), but only one pair is functional. The anterior pair (closest to the head) are very close to the axillae (armpit). Furless scent glands are present on both males and females. Both sexes have small, dark antebrachial (forearm) glands measuring 1 cm long and located on the inner surface of the forearm nearly 25 cm (9.8 in) above the wrist joint. (This trait is shared between the Lemur and Hapalemur genera.) The gland is soft and compressible, bears fine dermal ridges (like fingerprints), and is connected to the palm by a fine, 2 mm–high, hairless strip. However, only the male has a horny spur that overlays this scent gland. The spur develops with age through the accumulation of secretions from an underlying gland that may connect through the skin through as many as a thousand minuscule ducts. The males also have brachial (arm) glands on the axillary surface of their shoulders (near the armpit). The brachial gland is larger than the antebrachial gland, covered in short hair around the periphery, and has a naked crescent-shaped orifice near the center. The gland secretes a foul-smelling, brown, sticky substance. The brachial gland is barely developed if present at all in females. Both sexes also have apocrine and sebaceous glands in their genital or perianal regions, which are covered in fur.

 

Its fingers are slender, padded, mostly lacking webbing, and semi-dexterous with flat, human-like nails. The thumb is both short and widely separated from the other fingers. Despite being set at a right angle to the palm, the thumb is not opposable since the ball of the joint is fixed in place. As with all strepsirrhines, the hand is ectaxonic (the axis passes through the fourth digit) rather than mesaxonic (the axis passing through the third digit) as seen in monkeys and apes. The fourth digit is the longest, and only slightly longer than the second digit. Likewise, the fifth digit is only slightly longer than the second. The palms are long and leathery, and like other primates, they have dermal ridges to improve grip. The feet are semi-digitigrade and more specialized than the hands. The big toe is opposable and is smaller than the big toe of other lemurs, which are more arboreal. The second toe is short, has a small terminal pad, and has a toilet-claw (sometimes referred to as a grooming claw) specialized for personal grooming, specifically to rake through fur that is unreachable by the mouth. The toilet-claw is a trait shared among nearly all living strepsirrhine primates. Unlike other lemurs, the ring-tailed lemur's heel is not covered by fur.

 

Close-up of a ring-tailed lemur's toes, showing a claw-like nail on the second toe (compared to the nail on the third toe next to it)

Close-up of a ring-tailed lemur's hands, showing black skin and dermal ridges

Close-up of a ring-tailed lemur's foot, showing black skin and a lack of fur on the heel

Like other lemurs, the ring-tailed lemur has a claw-like nail (toilet-claw) on its second toe (left) and dermal ridges on its hands to improve its grip (center). Unlike other lemurs, it lacks fur on its heel (right).

Dentition

Close-up of the front, bottom teeth of a ring-tailed lemur, showing the first six teeth pointing directly forward instead of up-and-down like the canine-like premolar behind them.

The front, lower dentition includes a toothcomb (4 incisors and 2 canine teeth), while the first premolars resemble canines.

The ring-tailed lemur has a dentition of

2.1.3.3

2.1.3.3

 × 2 = 36, meaning that on each side of the jaw it has two incisors, one canine tooth, three premolars, and three molar teeth.[3] Its deciduous dentition is

2.1.3

2.1.3

 × 2 = 24. The permanent teeth erupt in the following order: m 1/1 (first molars), i 2/2 (first incisors), i 3/3 (second incisors), C1 (upper canines), m 2/2 (second molars), c1 (lower canines), m 3/3 (third molars), p 4/4 (third premolars), p 3/3 (second premolars), p 2/2 (first premolars).

 

Its lower incisors (i1 and i2) are long, narrow, and finely spaced while pointing almost straight forward in the mouth (procumbent). Together with the incisor-shaped (incisiform) lower canines (c1), which are slightly larger and also procumbent, form a structure called a toothcomb, a trait unique to nearly all strepsirrhine primates. The toothcomb is used during oral grooming, which involves licking and tooth-scraping. It may also be used for grasping small fruits, removing leaves from the stem when eating, and possibly scraping sap and gum from tree bark. The toothcomb is kept clean using a sublingual organ—a thin, flat, fibrous plate that covers a large part of the base of the tongue. The first lower premolar (p2) following the toothcomb is shaped like a canine (caniniform) and occludes the upper canine, essentially filling the role of the incisiform lower canine. There is also a diastema (gap) between the second and third premolars.

 

The upper incisors are small, with the first incisors space widely from each other, yet closely to the second incisors . Both are compressed buccolingually (between the cheek and the tongue). The upper canines (C1) are long, have a broad base, and curve down and back (recurved). The upper canines exhibit slight sexual dimorphism, with males exhibiting slightly larger canines than females. Both sexes use them in combat by slashing with them. There is a small diastema between the upper canine and the first premolar (P2), which is smaller and more caniniform than the other premolars. Unlike other lemurs, the first two upper molars (M1 and M2) have prominent lingual cingulae, yet do not have a protostyle.

 

Ecology

The ring-tailed lemur is diurnal and semi-terrestrial. It is the most terrestrial of lemur species, spending as much as 33% of its time on the ground. However it is still considerably arboreal, spending 23% of its time in the mid-level canopy, 25% in the upper-level canopy, 6% in the emergent layer and 13% in small bushes. Troop travel is 70% terrestrial.

 

Troop size, home range, and population density vary by region and food availability. Troops typically range in size from 6 to 25, although troops with over 30 individuals have been recorded. The average troop contains 13 to 15 individuals. Home range size varies between 6 and 35 hectares (15 and 86 acres). Troops of the ring-tailed lemur will maintain a territory, but overlap is often high. When encounters occur, they are agonistic, or hostile in nature. A troop will usually occupy the same part of its range for three or four days before moving. When it does move, the average traveling distance is 1 km (0.62 mi). Population density ranges from 100 individuals per 1 km2 (0.39 sq mi) in dry forests to 250–600 individuals per km2 in gallery and secondary forests.

 

The ring-tailed lemur has both native and introduced predators. Native predators include the fossa (Cryptoprocta ferox), the Madagascar harrier-hawk (Polyboroides radiatus), the Madagascar buzzard (Buteo brachypterus) and the Madagascar ground boa (Acrantophis madagascariensis). Introduced predators include the small Indian civet (Viverricula indica), the domestic cat and the domestic dog.

 

Geographic range and habitat

Endemic to southern and southwestern Madagascar, the ring-tailed lemur ranges further into highland areas than other lemurs. It inhabits deciduous forests, dry scrub, montane humid forests, and gallery forests (forests along riverbanks). It strongly favors gallery forests, but such forests have now been cleared from much of Madagascar in order to create pasture for livestock. Depending on location, temperatures within its geographic range can vary from −12 °C (10 °F) at Andringitra Massif to 48 °C (118 °F) in the spiny forests of Beza Mahafaly Special Reserve.

 

This species is found as far east as Tôlanaro, inland towards the mountains of Andringitra on the southeastern plateau, among the spiny forests of the southern part of the island, and north along the west coast to the town of Belo sur Mer. Historically, the northern limits of its range in the west extended to the Morondava River near Morondava. It can still be found in Kirindy Mitea National Park, just south of Morondava, though at very low densities. It does not occur in Kirindy Forest Reserve, north of Morondava. Its distribution throughout the rest of its range is very spotty, with population densities varying widely.

 

The ring-tailed lemur can be easily seen in five national parks in Madagascar: Andohahela National Park, Andringitra National Park, Isalo National Park, Tsimanampetsotse National Park, and Zombitse-Vohibasia National Park. It can also be found in Beza-Mahafaly Special Reserve, Kalambatritra Special Reserve, Pic d'Ivohibe Special Reserve, Amboasary Sud, Berenty Private Reserve, Anja Community Reserve, and marginally at Kirindy Mitea National Park. Unprotected forests that the species has been reported in include Ankoba, Ankodida, Anjatsikolo, Anbatotsilongolongo, Mahazoarivo, Masiabiby, and Mikea.

 

Within the protected regions it is known to inhabit, the ring-tailed lemur is sympatric (shares its range) with as many as 24 species of lemur, covering every living genus except Allocebus, Indri, and Varecia. Historically, the species used to be sympatric with the critically endangered southern black-and-white ruffed lemur (Varecia variegata editorum), which was once found at Andringitra National Park; however, no sightings of the ruffed lemur have been reported in recent years.

 

List of species sympatric with the ring-tailed lemur[38]

Verreaux's sifaka

(Propithecus verreauxi)

Milne-Edwards' sifaka

(Propithecus edwardsi)

Peyrieras' woolly lemur

(Avahi peyrierasi)

Gray mouse lemur

(Microcebus murinus)

Brown mouse lemur

(Microcebus rufus)

Reddish-gray mouse lemur

(Microcebus griseorufus)

Aye-aye

(Daubentonia madagascariensis)

Fat-tailed dwarf lemur

(Cheirogaleus medius)

Greater dwarf lemur

(Cheirogaleus major)

White-footed sportive lemur

(Lepilemur leucopus)

Small-toothed sportive lemur

(Lepilemur microdon)

Petter's sportive lemur

(Lepilemur petteri)

Red-tailed sportive lemur

(Lepilemur ruficaudatus)

Wright's sportive lemur

(Lepilemur wrightae)

Hubbard's sportive lemur

(Lepilemur hubbardorum)

Golden bamboo lemur

(Hapalemur aureus)

Southern lesser bamboo lemur

(Hapalemur meridionalis)

Greater bamboo lemur

(Prolemur simus)

Common brown lemur

(Eulemur fulvus)

Red-fronted lemur

(Eulemur rufifrons)

Red-bellied lemur

(Eulemur rubriventer)

Collared brown lemur

(Eulemur collaris)

Coquerel's giant mouse lemur

(Mirza coquereli)

Pale fork-marked lemur

(Phaner pallescens)[N 6]

In western Madagascar, sympatric ring-tailed lemurs and red-fronted lemurs (Eulemur rufifrons) have been studied together. Little interaction takes place between the two species. While the diets of the two species overlap, they eat in different proportions since the ring-tailed lemur has a more varied diet and spends more time on the ground.

 

Diet

The ring-tailed lemur is an opportunistic omnivore primarily eating fruits and leaves, particularly those of the tamarind tree (Tamarindus indica), known natively as kily. When available, tamarind makes up as much as 50% of the diet, especially during the dry, winter season. The ring-tailed lemur eats from as many as three dozen different plant species, and its diet includes flowers, herbs, bark and sap. It has been observed eating decayed wood, earth, spider webs, insect cocoons, arthropods (spiders, caterpillars, cicadas and grasshoppers) and small vertebrates (birds and chameleons). During the dry season it becomes increasingly opportunistic.

 

Behavior

Social systems

Troops are classified as multi-male groups, with a matriline as the core group. As with most lemurs, females socially dominate males in all circumstances, including feeding priority. Dominance is enforced by lunging, chasing, cuffing, grabbing and biting. Young females do not always inherit their mother's rank and young males leave the troop between three and five years of age. Both sexes have separate dominance hierarchies; females have a distinct hierarchy while male rank is correlated with age. Each troop has one to three central, high-ranking adult males who interact with females more than other group males and lead the troop procession with high-ranking females. Recently transferred males, old males or young adult males that have not yet left their natal group are often lower ranking. Staying at the periphery of the group they tend to be marginalized from group activity.

 

A group of three ring-tailed lemurs rest in the sun, with two sitting upright, facing the sun, with their arms to their sides.

The ring-tailed lemur will sit facing the sun to warm itself in the mornings.

For males, social structure changes can be seasonal. During the six-month period between December and May a few males migrate between groups. Established males transfer on average every 3.5 years, although young males may transfer approximately every 1.4 years. Group fission occurs when groups get too large and resources become scarce.

 

In the mornings the ring-tailed lemur sunbathes to warm itself. It faces the sun sitting in what is frequently described as a "sun-worshipping" posture or lotus position. However, it sits with its legs extended outward, not cross-legged, and will often support itself on nearby branches. Sunning is often a group activity, particularly during the cold mornings. At night, troops will split into sleeping parties huddling closely together to keep warm.

 

Despite being quadrupedal the ring-tailed lemur can rear up and balance on its hind legs, usually for aggressive displays. When threatened the ring-tailed lemur may jump in the air and strike out with its short nails and sharp upper canine teeth in a behaviour termed jump fighting. This is extremely rare outside of the breeding season when tensions are high and competition for mates is intense. Other aggressive behaviours include a threat-stare, used to intimidate or start a fight, and a submissive gesture known as pulled-back lips.

 

Border disputes with rival troops occur occasionally and it is the dominant female's responsibility to defend the troop's home range. Agonistic encounters include staring, lunging approaches and occasional physical aggression, and conclude with troop members retreating toward the center of the home range.

 

Olfactory communication

Olfactory communication is critically important for strepsirrhines like the ring-tailed lemur. Males and females scent mark both vertical and horizontal surfaces at the overlaps in their home ranges using their anogenital scent glands. The ring-tailed lemur will perform a handstand to mark vertical surfaces, grasping the highest point with its feet while it applies its scent. Use of scent marking varies by age, sex and social status. Male lemurs use their antebrachial and brachial glands to demarcate territories and maintain intragroup dominance hierarchies. The thorny spur that overlays the antebrachial gland on each wrist is scraped against tree trunks to create grooves anointed with their scent. This is known as spur-marking.

 

In displays of aggression, males engage in a social display behaviour called stink fighting, which involves impregnating their tails with secretions from the antebrachial and brachial glands and waving the scented tail at male rivals.

 

Ring-tailed lemurs have also been shown to mark using urine. Behaviorally, there is a difference between regular urination, where the tail is slightly raised and a stream of urine is produced, and the urine marking behavior, where the tail is held up in display and only a few drops of urine are used. The urine-marking behavior is typically used by females to mark territory, and has been observed primarily at the edges of the troop's territory and in areas where other troops may frequent. The urine marking behavior also is most frequent during the mating season, and may play a role in reproductive communication between groups.

 

Breeding and reproduction

The ring-tailed lemur is polygynandrous, although the dominant male in the troop typically breeds with more females than other males. Fighting is most common during the breeding season. A receptive female may initiate mating by presenting her backside, lifting her tail and looking at the desired male over her shoulder. Males may inspect the female's genitals to determine receptiveness. Females typically mate within their troop, but may seek outside males.

 

The breeding season runs from mid-April to mid-May. Estrus lasts 4 to 6 hours, and females mate with multiple males during this period. Within a troop, females stagger their receptivity so that each female comes into season on a different day during the breeding season, reducing competition for male attention. Females lactate during the wet season, from December through April, when resources are readily available. Females gestate during the dry season, from May through September, when resources are low. Females give birth during seasons where resources, such as flowers, are in peak. Gestation lasts for about 135 days, and parturition occurs in September or occasionally October. In the wild, one offspring is the norm, although twins may occur. Ring-tailed lemur infants have a birth weight of 70 g (2.5 oz) and are carried ventrally (on the chest) for the first 1 to 2 weeks, then dorsally (on the back).

 

The young lemurs begin to eat solid food after two months and are fully weaned after five months. Sexual maturity is reached between 2.5 and 3 years. Male involvement in infant rearing is limited, although the entire troop, regardless of age or sex, can be seen caring for the young. Alloparenting between troop females has been reported. Kidnapping by females and infanticide by males also occur occasionally. Due to harsh environmental conditions, predation and accidents such as falls, infant mortality can be as high as 50% within the first year and as few as 30% may reach adulthood. The longest-lived ring-tailed lemur in the wild was a female at the Berenty Reserve who lived for 20 years. In the wild, females rarely live past the age of 16, whereas the life expectancy of males is not known due to their social structure. The longest-lived male was reported to be 15 years old. The maximum lifespan reported in captivity was 27 years.

 

Cognitive abilities and tool use

Historically, the studies of learning and cognition in non-human primates have focused on simians (monkeys and apes), while strepsirrhine primates, such as the ring-tailed lemur and its allies, have been overlooked and popularly dismissed as unintelligent. A couple of factors stemming from early experiments have played a role in the development of this assumption. First, the experimental design of older tests may have favored the natural behavior and ecology of simians over that of strepsirrhines, making the experimental tasks inappropriate for lemurs. For example, simians are known for their manipulative play with non-food objects, whereas lemurs are only known to manipulate non-food objects in captivity. This behaviour is usually connected with food association. Also, lemurs are known to displace objects with their nose or mouth more so than with their hands. Therefore, an experiment requiring a lemur to manipulate an object without prior training would favor simians over strepsirrhines. Second, individual ring-tailed lemurs accustomed to living in a troop may not respond well to isolation for laboratory testing. Past studies have reported hysterical behaviour in such scenarios.

 

The notion that lemurs are unintelligent has been perpetuated by the view that the neocortex ratio (as a measure of brain size) indicates intelligence. In fact, primatologist Alison Jolly noted early in her academic career that some lemur species, such as the ring-tailed lemur, have evolved a social complexity similar to that of cercopithecine monkeys, but not the corresponding intelligence. After years of observations of wild ring-tailed lemur populations at the Berenty Reserve in Madagascar and as well as baboons in Africa, she more recently concluded that this highly social lemur species does not demonstrate the equivalent social complexity of cercopithecine monkeys, despite general appearances.

 

Regardless, research has continued to illuminate the complexity of the lemur mind, with emphasis on the cognitive abilities of the ring-tailed lemur. As early as the mid-1970s, studies had demonstrated that they could be trained through operant conditioning using standard schedules of reinforcement. The species has been shown to be capable of learning pattern, brightness, and object discrimination, skills common among vertebrates. The ring-tailed lemur has also been shown to learn a variety of complex tasks often equaling, if not exceeding, the performance of simians.

 

More recently, research at the Duke Lemur Center has shown that the ring-tailed lemur can organize sequences in memory and retrieve ordered sequences without language. The experimental design demonstrated that the lemurs were using internal representation of the sequence to guide their responses and not simply following a trained sequence, where one item in the sequence cues the selection of the next. But this is not the limit of the ring-tailed lemur's reasoning skills. Another study, performed at the Myakka City Lemur Reserve, suggests that this species along with several other closely related lemur species understand simple arithmetic operations.

 

Since tool use is considered to be a key feature of primate intelligence, the apparent lack of this behavior in wild lemurs, as well as the lack of non-food object play, has helped reinforce the perception that lemurs are less intelligent than their simian cousins. However, another study at the Myakka City Lemur Reserve examined the representation of tool functionality in both the ring-tailed lemur and the common brown lemur and discovered that, like monkeys, they used tools with functional properties (e.g., tool orientation or ease of use) instead of tools with nonfunctional features (e.g., color or texture). Although the ring-tailed lemur may not use tools in the wild, it can not only be trained to use a tool, but will preferentially select tools based on their functional qualities. Therefore, the conceptual competence to use a tool may have been present in the common primate ancestor, even though the use of tools may not have appeared until much later.

 

Conservation status

In addition to being listed as endangered in 2014 by the IUCN, the ring-tailed lemur has been listed since 1977 by CITES under Appendix I, which makes trade of wild-caught specimens illegal. Although there are more endangered species of lemur, the ring-tailed lemur is considered a flagship species due to its recognizability. As of 2017, only about 2,000 ring-tailed lemurs are estimated to be left in the wild, making the threat of extinction far more serious for them than previously believed.

 

hree factors threaten ring-tailed lemurs. First and foremost is habitat destruction. Starting nearly 2,000 years ago with the introduction of humans to the island, forests have been cleared to produce pasture and agricultural land. Extraction of hardwoods for fuel and lumber, as well mining and overgrazing, have also taken their toll. Today, it is estimated that 90% of Madagascar's original forest cover has been lost.[61] Rising populations have created even greater demand in the southwest portion of the island for fuel wood, charcoal, and lumber. Fires from the clearing of grasslands, as well as slash-and-burn agriculture destroy forests. Another threat to the species is harvesting either for food (bushmeat), fur clothing or pets. Finally, periodic drought common to southern Madagascar can impact populations already in decline. In 1991 and 1992, for example, a severe drought caused an abnormally high mortality rate among infants and females at the Beza Mahafaly Special Reserve. Two years later, the population had declined by 31% and took nearly four years to start to recover.

 

The ring-tailed lemur resides in several protected areas within its range, each offering varying levels of protection. At the Beza Mahafaly Special Reserve, a holistic approach to in-situ conservation has been taken. Not only does field research and resource management involve international students and local people (including school children), livestock management is used at the peripheral zones of the reserve and ecotourism benefits the local people.

 

Outside of its diminishing habitat and other threats, the ring-tailed lemur reproduces readily and has fared well in captivity. For this reason, along with its popularity, it has become the most populous lemur in zoos worldwide, with more than 2500 in captivity as of 2009. It is also the most common of all captive primates. Ex situ facilities actively involved in the conservation of the ring-tailed lemur include the Duke Lemur Center in Durham, North Carolina, the Lemur Conservation Foundation in Myakka City, Florida, and the Madagascar Fauna Group headquartered at the Saint Louis Zoo. Due to the high success of captive breeding, reintroduction is a possibility if wild populations were to crash. Although experimental releases have met success on St. Catherines Island in Georgia, demonstrating that captive lemurs can readily adapt to their environment and exhibit a full range of natural behaviors, captive release is not currently being considered.

 

Ring-tailed lemur populations can also benefit from drought intervention, due to the availability of watering troughs and introduced fruit trees, as seen at the Berenty Private Reserve in southern Madagascar. However, these interventions are not always seen favorably, since natural population fluctuations are not permitted. The species is thought to have evolved its high fecundity due to its harsh environment.

 

Cultural references

The ring-tailed lemur is known locally in Malagasy as maky (pronounced [ˈmakʲi̥], and spelled maki in French) or hira (pronounced [ˈhirə] or colloquially [ˈir]). Being the most widely recognized endemic primate on the island, it has been selected as the symbol for Madagascar National Parks (formerly known as ANGAP). The Maki brand, which started by selling T-shirts in Madagascar and now sells clothing across the Indian Ocean islands, is named after this lemur due to its popularity, even though the company's logo portrays the face of a sifaka and its name uses the French spelling.

 

The first mention of the ring-tailed lemur in Western literature came in 1625 when English traveller and writer Samuel Purchas described them as being comparable in size to a monkey and having a fox-like long tail with black and white rings. Charles Catton included the species in his 1788 book Animals Drawn from Nature and Engraved in Aqua-tinta, calling it the "Maucauco" and regarding it as a type of monkey.

 

A Ring-tailed lemur named Dotty regularly appeared with Jonny Morris on the BBC television programme Animal Magic.

 

The species was further popularized by the Animal Planet television series Lemur Street, as well as by the character King Julien in the animated Madagascar film and TV franchise.[69] The ring-tailed lemur was also the focus of the 1996 Nature documentary A Lemur's Tale, which was filmed at the Berenty Reserve and followed a troop of lemurs. The troop included a special infant named Sapphire, who was nearly albino, with white fur, bright blue eyes, and the characteristic ringed tail.

 

A Ring-tailed lemur played a role in the 1997 comedy film Fierce Creatures, starring John Cleese, who has a passion for lemurs. Cleese later hosted the 1998 BBC documentary In the Wild: Operation Lemur with John Cleese, which tracked the progress of a reintroduction of black-and-white ruffed lemurs back into the Betampona Reserve in Madagascar. The project had been partly funded by Cleese's donation of the proceeds from the London premier of Fierce Creatures.

Mursi woman without her giant lip plate, a sign of beauty in Mursi tribe, like in Surma one. When they are ready to marry, they start to make a hole in the lip with a wood stick.

It will be kept for one night , and is removed to put a bigger one. This is very painful at this time... Few months after, the lip plate has its full size, and the girl is seen as beautiful by the men.

The lip plate made of wood or terracotta, and they have to remove the lower incisors to let some space for the disc. it's amazing to see them speak without any trouble, put it and remove it as a classic jewel.

Sometimes the lip is broken by the pressure of the lip plate. This is a very big problem for the girl cos men will consider her as ugly, she won't be able to marry anyone in the tribe apart the old men or the sick people...

On this picture, a Mursi, the most agressive tribe i met.

Agressive in the way that when you come to see them (after hours of 4x4 on a very bad track), they only think about the money they can get from you! The craziest thing is that they ask for a fee to park the car (20 euros!) at the entrance of the village!!

They tend to use more and more things to decorate themselves and attract photographers!

You may have seen or read books about this area by great photographers those last years, and many of the people inside are just "disguised"...

But at the end, those tribes really live like in the primitives times, whitout anything around apart their cattle, and still fighting with other tribes to catch cows and women...

This is a daily reality in this area of the world!

7 000 tourists visit the mursis every year. It makes an average of 20 by day in a very big area, so it's very few.But as 70% are from Spain and pay a low fee to the tour operator, some tribes start to settle close to "hotels" or campings to get money from the photographers.

I had the chance to go in Omo valley with a guide who avoid those touristic spots.

The women are shaved, like the men, cos they hate hairiness!

 

© Eric Lafforgue

www.ericlafforgue.com

The brown-throated sloth (Bradypus variegatus) is a species of three-toed sloth found in the neotropical ecozone.

 

It is the most common of the four species of three-toed sloth, and is found in the forests of South and Central America.

 

The brown-throated sloth is of similar size and build to most other species of three-toed sloth, with both males and females being 42 to 80 centimetres (17 to 31 in) in total body length. The tail is relatively short, only 2.5 to 9 cm (1.0 to 3.5 in) long. Adults weigh from 2.25 to 6.3 kg (5.0 to 13.9 lb), with no significant size difference between males and females. Each foot has three fingers, ending in long, curved claws, which are 7 to 8 cm (2.8 to 3.1 in) long on the fore feet, and 5 to 5.5 cm (2.0 to 2.2 in) on the hind feet.

 

The head is rounded, with a blunt nose and inconspicuous ears. As with other sloths, the brown-throated sloth has no incisor or canine teeth, and the cheek teeth are simple and peg-like. They have no gall bladder, cecum, or appendix.

 

The brown-throated sloth has grayish-brown to beige-color fur over the body, with darker brown fur on the throat, the sides of the face, and the forehead. The face is generally paler in colour, with a stripe of very dark fur running beneath the eyes.

 

The guard hairs are very coarse and stiff, and overlie a much softer layer of dense under-fur. The hairs are unusual in lacking a central medulla, and have numerous microscopic cracks across their surfaces. These cracks are host to a number of commensal species of algae, including Rufusia pillicola, Dictyococcus bradypodis, and Chlorococcum choloepodis. The algae are generally absent in the hair of young sloths, and may also be absent in particularly old individuals, where the outer cuticle of the hair has been lost. Sloth hair also harbours a rich fungal flora.

 

Over parts of its range, the brown-throated sloth overlaps the range of Hoffmann's two-toed sloth. Where this overlap occurs, the three-toed sloth tends to be smaller and more numerous than its relative, being more active in moving through the forest and maintaining more diurnal activity.

 

This image was taken in near Lake Maica, close to Santarem, along the Amazon River in Brazil. The Sloth was very very slowly climbing down from the top of the tree.

The Alaska moose (Alces alces gigas) or giant moose or Alaskan moose is a subspecies of moose that ranges from Alaska to western Yukon. The Alaska moose is the largest subspecies of moose. Alaska moose inhabit boreal forests and mixed deciduous forests throughout most of Alaska and most of Western Yukon. Like all moose species, the Alaska moose is usually solitary but sometimes will form small herds. Typically, they only come into contact with other moose for mating or competition for mates. During mating season, in autumn and winter, male Alaska moose become very aggressive and prone to attacking when startled.

 

The Alaska moose ranges throughout Alaska, to most of the western Yukon, Canada. Due to its large range, humans frequently come into contact with the moose. Alaska moose inhabit isolated forests, which helps the moose hide from predators such as wolves. There is a large population of about 225,000 individuals. To keep the Alaska moose have a similar diet to other moose subspecies, consisting of terrestrial vegetation forbs and shoots from trees such as willow and birch.

 

Alaska moose require a daily intake of 9770 calories (32 kg). Alaska moose lack upper front teeth but have eight sharp incisors on their lower jaw. They also have a tough tongue, gums and lips to help chew woody vegetation. of Alaska moose in balance, they are routinely hunted by people every autumn and winter.

 

Male Alaska moose can stand over 2.1 m (6.9 ft) at the shoulder, and weigh over 634.5 kg (1,399 lb). The antlers on average have a span of 1.8 m (5.9 ft). Female Alaska moose stand on average 1.8 m (5.9 ft) at the shoulder and can weigh close to 478 kg (1,054 lb).[1] The largest Alaska moose was shot in western Yukon in September 1897; it weighed 820 kg (1,808 lb), and was 2.33 m (7.6 ft) tall at the shoulder. Alaska moose with the Chukotka moose, matches the extinct Irish elk as the largest deer of all time.

 

This image was taken in Denali, Alaska

Fish, any of approximately 34,000 species of vertebrate animals (phylum Chordata) found in the fresh and salt waters of the world. Living species range from the primitive jawless lampreys and hagfishes through the cartilaginous sharks, skates, and rays to the abundant and diverse bony fishes. Most fish species are cold-blooded; however, one species, the opah (Lampris guttatus), is warm-blooded.

 

The term fish is applied to a variety of vertebrates of several evolutionary lines. It describes a life-form rather than a taxonomic group. As members of the phylum Chordata, fish share certain features with other vertebrates. These features are gill slits at some point in the life cycle, a notochord, or skeletal supporting rod, a dorsal hollow nerve cord, and a tail. Living fishes represent some five classes, which are as distinct from one another as are the four classes of familiar air-breathing animals—amphibians, reptiles, birds, and mammals. For example, the jawless fishes (Agnatha) have gills in pouches and lack limb girdles. Extant agnathans are the lampreys and the hagfishes. As the name implies, the skeletons of fishes of the class Chondrichthyes (from chondr, “cartilage,” and ichthyes, “fish”) are made entirely of cartilage. Modern fish of this class lack a swim bladder, and their scales and teeth are made up of the same placoid material. Sharks, skates, and rays are examples of cartilaginous fishes. The bony fishes are by far the largest class. Examples range from the tiny seahorse to the 450-kg (1,000-pound) blue marlin, from the flattened soles and flounders to the boxy puffers and ocean sunfishes. Unlike the scales of the cartilaginous fishes, those of bony fishes, when present, grow throughout life and are made up of thin overlapping plates of bone. Bony fishes also have an operculum that covers the gill slits.

 

The study of fishes, the science of ichthyology, is of broad importance. Fishes are of interest to humans for many reasons, the most important being their relationship with and dependence on the environment. A more obvious reason for interest in fishes is their role as a moderate but important part of the world’s food supply. This resource, once thought unlimited, is now realized to be finite and in delicate balance with the biological, chemical, and physical factors of the aquatic environment. Overfishing, pollution, and alteration of the environment are the chief enemies of proper fisheries management, both in fresh waters and in the ocean. (For a detailed discussion of the technology and economics of fisheries, see commercial fishing.) Another practical reason for studying fishes is their use in disease control. As predators on mosquito larvae, they help curb malaria and other mosquito-borne diseases.

 

Fishes are valuable laboratory animals in many aspects of medical and biological research. For example, the readiness of many fishes to acclimate to captivity has allowed biologists to study behaviour, physiology, and even ecology under relatively natural conditions. Fishes have been especially important in the study of animal behaviour, where research on fishes has provided a broad base for the understanding of the more flexible behaviour of the higher vertebrates. The zebra fish is used as a model in studies of gene expression.

 

There are aesthetic and recreational reasons for an interest in fishes. Millions of people keep live fishes in home aquariums for the simple pleasure of observing the beauty and behaviour of animals otherwise unfamiliar to them. Aquarium fishes provide a personal challenge to many aquarists, allowing them to test their ability to keep a small section of the natural environment in their homes. Sportfishing is another way of enjoying the natural environment, also indulged in by millions of people every year. Interest in aquarium fishes and sportfishing supports multimillion-dollar industries throughout the world.

 

Fishes have been in existence for more than 450 million years, during which time they have evolved repeatedly to fit into almost every conceivable type of aquatic habitat. In a sense, land vertebrates are simply highly modified fishes: when fishes colonized the land habitat, they became tetrapod (four-legged) land vertebrates. The popular conception of a fish as a slippery, streamlined aquatic animal that possesses fins and breathes by gills applies to many fishes, but far more fishes deviate from that conception than conform to it. For example, the body is elongate in many forms and greatly shortened in others; the body is flattened in some (principally in bottom-dwelling fishes) and laterally compressed in many others; the fins may be elaborately extended, forming intricate shapes, or they may be reduced or even lost; and the positions of the mouth, eyes, nostrils, and gill openings vary widely. Air breathers have appeared in several evolutionary lines.

 

Many fishes are cryptically coloured and shaped, closely matching their respective environments; others are among the most brilliantly coloured of all organisms, with a wide range of hues, often of striking intensity, on a single individual. The brilliance of pigments may be enhanced by the surface structure of the fish, so that it almost seems to glow. A number of unrelated fishes have actual light-producing organs. Many fishes are able to alter their coloration—some for the purpose of camouflage, others for the enhancement of behavioral signals.

 

Fishes range in adult length from less than 10 mm (0.4 inch) to more than 20 metres (60 feet) and in weight from about 1.5 grams (less than 0.06 ounce) to many thousands of kilograms. Some live in shallow thermal springs at temperatures slightly above 42 °C (100 °F), others in cold Arctic seas a few degrees below 0 °C (32 °F) or in cold deep waters more than 4,000 metres (13,100 feet) beneath the ocean surface. The structural and, especially, the physiological adaptations for life at such extremes are relatively poorly known and provide the scientifically curious with great incentive for study.

 

Almost all natural bodies of water bear fish life, the exceptions being very hot thermal ponds and extremely salt-alkaline lakes, such as the Dead Sea in Asia and the Great Salt Lake in North America. The present distribution of fishes is a result of the geological history and development of Earth as well as the ability of fishes to undergo evolutionary change and to adapt to the available habitats. Fishes may be seen to be distributed according to habitat and according to geographical area. Major habitat differences are marine and freshwater. For the most part, the fishes in a marine habitat differ from those in a freshwater habitat, even in adjacent areas, but some, such as the salmon, migrate from one to the other. The freshwater habitats may be seen to be of many kinds. Fishes found in mountain torrents, Arctic lakes, tropical lakes, temperate streams, and tropical rivers will all differ from each other, both in obvious gross structure and in physiological attributes. Even in closely adjacent habitats where, for example, a tropical mountain torrent enters a lowland stream, the fish fauna will differ. The marine habitats can be divided into deep ocean floors (benthic), mid-water oceanic (bathypelagic), surface oceanic (pelagic), rocky coast, sandy coast, muddy shores, bays, estuaries, and others. Also, for example, rocky coastal shores in tropical and temperate regions will have different fish faunas, even when such habitats occur along the same coastline.

 

Although much is known about the present geographical distribution of fishes, far less is known about how that distribution came about. Many parts of the fish fauna of the fresh waters of North America and Eurasia are related and undoubtedly have a common origin. The faunas of Africa and South America are related, extremely old, and probably an expression of the drifting apart of the two continents. The fauna of southern Asia is related to that of Central Asia, and some of it appears to have entered Africa. The extremely large shore-fish faunas of the Indian and tropical Pacific oceans comprise a related complex, but the tropical shore fauna of the Atlantic, although containing Indo-Pacific components, is relatively limited and probably younger. The Arctic and Antarctic marine faunas are quite different from each other. The shore fauna of the North Pacific is quite distinct, and that of the North Atlantic more limited and probably younger. Pelagic oceanic fishes, especially those in deep waters, are similar the world over, showing little geographical isolation in terms of family groups. The deep oceanic habitat is very much the same throughout the world, but species differences do exist, showing geographical areas determined by oceanic currents and water masses.

 

All aspects of the life of a fish are closely correlated with adaptation to the total environment, physical, chemical, and biological. In studies, all the interdependent aspects of fish, such as behaviour, locomotion, reproduction, and physical and physiological characteristics, must be taken into account.

 

Correlated with their adaptation to an extremely wide variety of habitats is the extremely wide variety of life cycles that fishes display. The great majority hatch from relatively small eggs a few days to several weeks or more after the eggs are scattered in the water. Newly hatched young are still partially undeveloped and are called larvae until body structures such as fins, skeleton, and some organs are fully formed. Larval life is often very short, usually less than a few weeks, but it can be very long, some lampreys continuing as larvae for at least five years. Young and larval fishes, before reaching sexual maturity, must grow considerably, and their small size and other factors often dictate that they live in a habitat different than that of the adults. For example, most tropical marine shore fishes have pelagic larvae. Larval food also is different, and larval fishes often live in shallow waters, where they may be less exposed to predators.

 

After a fish reaches adult size, the length of its life is subject to many factors, such as innate rates of aging, predation pressure, and the nature of the local climate. The longevity of a species in the protected environment of an aquarium may have nothing to do with how long members of that species live in the wild. Many small fishes live only one to three years at the most. In some species, however, individuals may live as long as 10 or 20 or even 100 years.

 

Fish behaviour is a complicated and varied subject. As in almost all animals with a central nervous system, the nature of a response of an individual fish to stimuli from its environment depends upon the inherited characteristics of its nervous system, on what it has learned from past experience, and on the nature of the stimuli. Compared with the variety of human responses, however, that of a fish is stereotyped, not subject to much modification by “thought” or learning, and investigators must guard against anthropomorphic interpretations of fish behaviour.

 

Fishes perceive the world around them by the usual senses of sight, smell, hearing, touch, and taste and by special lateral line water-current detectors. In the few fishes that generate electric fields, a process that might best be called electrolocation aids in perception. One or another of these senses often is emphasized at the expense of others, depending upon the fish’s other adaptations. In fishes with large eyes, the sense of smell may be reduced; others, with small eyes, hunt and feed primarily by smell (such as some eels).

 

Specialized behaviour is primarily concerned with the three most important activities in the fish’s life: feeding, reproduction, and escape from enemies. Schooling behaviour of sardines on the high seas, for instance, is largely a protective device to avoid enemies, but it is also associated with and modified by their breeding and feeding requirements. Predatory fishes are often solitary, lying in wait to dart suddenly after their prey, a kind of locomotion impossible for beaked parrot fishes, which feed on coral, swimming in small groups from one coral head to the next. In addition, some predatory fishes that inhabit pelagic environments, such as tunas, often school.

 

Sleep in fishes, all of which lack true eyelids, consists of a seemingly listless state in which the fish maintains its balance but moves slowly. If attacked or disturbed, most can dart away. A few kinds of fishes lie on the bottom to sleep. Most catfishes, some loaches, and some eels and electric fishes are strictly nocturnal, being active and hunting for food during the night and retiring during the day to holes, thick vegetation, or other protective parts of the environment.

 

Communication between members of a species or between members of two or more species often is extremely important, especially in breeding behaviour (see below Reproduction). The mode of communication may be visual, as between the small so-called cleaner fish and a large fish of a very different species. The larger fish often allows the cleaner to enter its mouth to remove gill parasites. The cleaner is recognized by its distinctive colour and actions and therefore is not eaten, even if the larger fish is normally a predator. Communication is often chemical, signals being sent by specific chemicals called pheromones.

 

Many fishes have a streamlined body and swim freely in open water. Fish locomotion is closely correlated with habitat and ecological niche (the general position of the animal to its environment).

 

Many fishes in both marine and fresh waters swim at the surface and have mouths adapted to feed best (and sometimes only) at the surface. Often such fishes are long and slender, able to dart at surface insects or at other surface fishes and in turn to dart away from predators; needlefishes, halfbeaks, and topminnows (such as killifish and mosquito fish) are good examples. Oceanic flying fishes escape their predators by gathering speed above the water surface, with the lower lobe of the tail providing thrust in the water. They then glide hundreds of yards on enlarged, winglike pectoral and pelvic fins. South American freshwater flying fishes escape their enemies by jumping and propelling their strongly keeled bodies out of the water.

 

So-called mid-water swimmers, the most common type of fish, are of many kinds and live in many habitats. The powerful fusiform tunas and the trouts, for example, are adapted for strong, fast swimming, the tunas to capture prey speedily in the open ocean and the trouts to cope with the swift currents of streams and rivers. The trout body form is well adapted to many habitats. Fishes that live in relatively quiet waters such as bays or lake shores or slow rivers usually are not strong, fast swimmers but are capable of short, quick bursts of speed to escape a predator. Many of these fishes have their sides flattened, examples being the sunfish and the freshwater angelfish of aquarists. Fish associated with the bottom or substrate usually are slow swimmers. Open-water plankton-feeding fishes almost always remain fusiform and are capable of rapid, strong movement (for example, sardines and herrings of the open ocean and also many small minnows of streams and lakes).

 

Bottom-living fishes are of many kinds and have undergone many types of modification of their body shape and swimming habits. Rays, which evolved from strong-swimming mid-water sharks, usually stay close to the bottom and move by undulating their large pectoral fins. Flounders live in a similar habitat and move over the bottom by undulating the entire body. Many bottom fishes dart from place to place, resting on the bottom between movements, a motion common in gobies. One goby relative, the mudskipper, has taken to living at the edge of pools along the shore of muddy mangrove swamps. It escapes its enemies by flipping rapidly over the mud, out of the water. Some catfishes, synbranchid eels, the so-called climbing perch, and a few other fishes venture out over damp ground to find more promising waters than those that they left. They move by wriggling their bodies, sometimes using strong pectoral fins; most have accessory air-breathing organs. Many bottom-dwelling fishes live in mud holes or rocky crevices. Marine eels and gobies commonly are found in such habitats and for the most part venture far beyond their cavelike homes. Some bottom dwellers, such as the clingfishes (Gobiesocidae), have developed powerful adhesive disks that enable them to remain in place on the substrate in areas such as rocky coasts, where the action of the waves is great.

 

The methods of reproduction in fishes are varied, but most fishes lay a large number of small eggs, fertilized and scattered outside of the body. The eggs of pelagic fishes usually remain suspended in the open water. Many shore and freshwater fishes lay eggs on the bottom or among plants. Some have adhesive eggs. The mortality of the young and especially of the eggs is very high, and often only a few individuals grow to maturity out of hundreds, thousands, and in some cases millions of eggs laid.

 

Males produce sperm, usually as a milky white substance called milt, in two (sometimes one) testes within the body cavity. In bony fishes a sperm duct leads from each testis to a urogenital opening behind the vent or anus. In sharks and rays and in cyclostomes the duct leads to a cloaca. Sometimes the pelvic fins are modified to help transmit the milt to the eggs at the female’s vent or on the substrate where the female has placed them. Sometimes accessory organs are used to fertilize females internally—for example, the claspers of many sharks and rays.

 

In the females the eggs are formed in two ovaries (sometimes only one) and pass through the ovaries to the urogenital opening and to the outside. In some fishes the eggs are fertilized internally but are shed before development takes place. Members of about a dozen families each of bony fishes (teleosts) and sharks bear live young. Many skates and rays also bear live young. In some bony fishes the eggs simply develop within the female, the young emerging when the eggs hatch (ovoviviparous). Others develop within the ovary and are nourished by ovarian tissues after hatching (viviparous). There are also other methods utilized by fishes to nourish young within the female. In all live-bearers the young are born at a relatively large size and are few in number. In one family of primarily marine fishes, the surfperches from the Pacific coast of North America, Japan, and Korea, the males of at least one species are born sexually mature, although they are not fully grown.

 

Some fishes are hermaphroditic—an individual producing both sperm and eggs, usually at different stages of its life. Self-fertilization, however, is probably rare.

 

Successful reproduction and, in many cases, defense of the eggs and the young are assured by rather stereotypical but often elaborate courtship and parental behaviour, either by the male or the female or both. Some fishes prepare nests by hollowing out depressions in the sand bottom (cichlids, for example), build nests with plant materials and sticky threads excreted by the kidneys (sticklebacks), or blow a cluster of mucus-covered bubbles at the water surface (gouramis). The eggs are laid in these structures. Some varieties of cichlids and catfishes incubate eggs in their mouths.

 

Some fishes, such as salmon, undergo long migrations from the ocean and up large rivers to spawn in the gravel beds where they themselves hatched (anadromous fishes). Some, such as the freshwater eels (family Anguillidae), live and grow to maturity in fresh water and migrate to the sea to spawn (catadromous fishes). Other fishes undertake shorter migrations from lakes into streams, within the ocean, or enter spawning habitats that they do not ordinarily occupy in other ways.

 

The basic structure and function of the fish body are similar to those of all other vertebrates. The usual four types of tissues are present: surface or epithelial, connective (bone, cartilage, and fibrous tissues, as well as their derivative, blood), nerve, and muscle tissues. In addition, the fish’s organs and organ systems parallel those of other vertebrates.

 

The typical fish body is streamlined and spindle-shaped, with an anterior head, a gill apparatus, and a heart, the latter lying in the midline just below the gill chamber. The body cavity, containing the vital organs, is situated behind the head in the lower anterior part of the body. The anus usually marks the posterior termination of the body cavity and most often occurs just in front of the base of the anal fin. The spinal cord and vertebral column continue from the posterior part of the head to the base of the tail fin, passing dorsal to the body cavity and through the caudal (tail) region behind the body cavity. Most of the body is of muscular tissue, a high proportion of which is necessitated by swimming. In the course of evolution this basic body plan has been modified repeatedly into the many varieties of fish shapes that exist today.

 

The skeleton forms an integral part of the fish’s locomotion system, as well as serving to protect vital parts. The internal skeleton consists of the skull bones (except for the roofing bones of the head, which are really part of the external skeleton), the vertebral column, and the fin supports (fin rays). The fin supports are derived from the external skeleton but will be treated here because of their close functional relationship to the internal skeleton. The internal skeleton of cyclostomes, sharks, and rays is of cartilage; that of many fossil groups and some primitive living fishes is mostly of cartilage but may include some bone. In place of the vertebral column, the earliest vertebrates had a fully developed notochord, a flexible stiff rod of viscous cells surrounded by a strong fibrous sheath. During the evolution of modern fishes the rod was replaced in part by cartilage and then by ossified cartilage. Sharks and rays retain a cartilaginous vertebral column; bony fishes have spool-shaped vertebrae that in the more primitive living forms only partially replace the notochord. The skull, including the gill arches and jaws of bony fishes, is fully, or at least partially, ossified. That of sharks and rays remains cartilaginous, at times partially replaced by calcium deposits but never by true bone.

 

The supportive elements of the fins (basal or radial bones or both) have changed greatly during fish evolution. Some of these changes are described in the section below (Evolution and paleontology). Most fishes possess a single dorsal fin on the midline of the back. Many have two and a few have three dorsal fins. The other fins are the single tail and anal fins and paired pelvic and pectoral fins. A small fin, the adipose fin, with hairlike fin rays, occurs in many of the relatively primitive teleosts (such as trout) on the back near the base of the caudal fin.

 

The skin of a fish must serve many functions. It aids in maintaining the osmotic balance, provides physical protection for the body, is the site of coloration, contains sensory receptors, and, in some fishes, functions in respiration. Mucous glands, which aid in maintaining the water balance and offer protection from bacteria, are extremely numerous in fish skin, especially in cyclostomes and teleosts. Since mucous glands are present in the modern lampreys, it is reasonable to assume that they were present in primitive fishes, such as the ancient Silurian and Devonian agnathans. Protection from abrasion and predation is another function of the fish skin, and dermal (skin) bone arose early in fish evolution in response to this need. It is thought that bone first evolved in skin and only later invaded the cartilaginous areas of the fish’s body, to provide additional support and protection. There is some argument as to which came first, cartilage or bone, and fossil evidence does not settle the question. In any event, dermal bone has played an important part in fish evolution and has different characteristics in different groups of fishes. Several groups are characterized at least in part by the kind of bony scales they possess.

 

Scales have played an important part in the evolution of fishes. Primitive fishes usually had thick bony plates or thick scales in several layers of bone, enamel, and related substances. Modern teleost fishes have scales of bone, which, while still protective, allow much more freedom of motion in the body. A few modern teleosts (some catfishes, sticklebacks, and others) have secondarily acquired bony plates in the skin. Modern and early sharks possessed placoid scales, a relatively primitive type of scale with a toothlike structure, consisting of an outside layer of enamel-like substance (vitrodentine), an inner layer of dentine, and a pulp cavity containing nerves and blood vessels. Primitive bony fishes had thick scales of either the ganoid or the cosmoid type. Cosmoid scales have a hard, enamel-like outer layer, an inner layer of cosmine (a form of dentine), and then a layer of vascular bone (isopedine). In ganoid scales the hard outer layer is different chemically and is called ganoin. Under this is a cosminelike layer and then a vascular bony layer. The thin, translucent bony scales of modern fishes, called cycloid and ctenoid (the latter distinguished by serrations at the edges), lack enameloid and dentine layers.

 

Skin has several other functions in fishes. It is well supplied with nerve endings and presumably receives tactile, thermal, and pain stimuli. Skin is also well supplied with blood vessels. Some fishes breathe in part through the skin, by the exchange of oxygen and carbon dioxide between the surrounding water and numerous small blood vessels near the skin surface.

 

Skin serves as protection through the control of coloration. Fishes exhibit an almost limitless range of colours. The colours often blend closely with the surroundings, effectively hiding the animal. Many fishes use bright colours for territorial advertisement or as recognition marks for other members of their own species, or sometimes for members of other species. Many fishes can change their colour to a greater or lesser degree, by movement of pigment within the pigment cells (chromatophores). Black pigment cells (melanophores), of almost universal occurrence in fishes, are often juxtaposed with other pigment cells. When placed beneath iridocytes or leucophores (bearing the silvery or white pigment guanine), melanophores produce structural colours of blue and green. These colours are often extremely intense, because they are formed by refraction of light through the needlelike crystals of guanine. The blue and green refracted colours are often relatively pure, lacking the red and yellow rays, which have been absorbed by the black pigment (melanin) of the melanophores. Yellow, orange, and red colours are produced by erythrophores, cells containing the appropriate carotenoid pigments. Other colours are produced by combinations of melanophores, erythrophores, and iridocytes.

 

The major portion of the body of most fishes consists of muscles. Most of the mass is trunk musculature, the fin muscles usually being relatively small. The caudal fin is usually the most powerful fin, being moved by the trunk musculature. The body musculature is usually arranged in rows of chevron-shaped segments on each side. Contractions of these segments, each attached to adjacent vertebrae and vertebral processes, bends the body on the vertebral joint, producing successive undulations of the body, passing from the head to the tail, and producing driving strokes of the tail. It is the latter that provides the strong forward movement for most fishes.

 

The digestive system, in a functional sense, starts at the mouth, with the teeth used to capture prey or collect plant foods. Mouth shape and tooth structure vary greatly in fishes, depending on the kind of food normally eaten. Most fishes are predacious, feeding on small invertebrates or other fishes and have simple conical teeth on the jaws, on at least some of the bones of the roof of the mouth, and on special gill arch structures just in front of the esophagus. The latter are throat teeth. Most predacious fishes swallow their prey whole, and the teeth are used for grasping and holding prey, for orienting prey to be swallowed (head first) and for working the prey toward the esophagus. There are a variety of tooth types in fishes. Some fishes, such as sharks and piranhas, have cutting teeth for biting chunks out of their victims. A shark’s tooth, although superficially like that of a piranha, appears in many respects to be a modified scale, while that of the piranha is like that of other bony fishes, consisting of dentine and enamel. Parrot fishes have beaklike mouths with short incisor-like teeth for breaking off coral and have heavy pavementlike throat teeth for crushing the coral. Some catfishes have small brushlike teeth, arranged in rows on the jaws, for scraping plant and animal growth from rocks. Many fishes (such as the Cyprinidae or minnows) have no jaw teeth at all but have very strong throat teeth.

 

Some fishes gather planktonic food by straining it from their gill cavities with numerous elongate stiff rods (gill rakers) anchored by one end to the gill bars. The food collected on these rods is passed to the throat, where it is swallowed. Most fishes have only short gill rakers that help keep food particles from escaping out the mouth cavity into the gill chamber.

 

Once reaching the throat, food enters a short, often greatly distensible esophagus, a simple tube with a muscular wall leading into a stomach. The stomach varies greatly in fishes, depending upon the diet. In most predacious fishes it is a simple straight or curved tube or pouch with a muscular wall and a glandular lining. Food is largely digested there and leaves the stomach in liquid form.

 

Between the stomach and the intestine, ducts enter the digestive tube from the liver and pancreas. The liver is a large, clearly defined organ. The pancreas may be embedded in it, diffused through it, or broken into small parts spread along some of the intestine. The junction between the stomach and the intestine is marked by a muscular valve. Pyloric ceca (blind sacs) occur in some fishes at this junction and have a digestive or absorptive function or both.

 

The intestine itself is quite variable in length, depending upon the fish’s diet. It is short in predacious forms, sometimes no longer than the body cavity, but long in herbivorous forms, being coiled and several times longer than the entire length of the fish in some species of South American catfishes. The intestine is primarily an organ for absorbing nutrients into the bloodstream. The larger its internal surface, the greater its absorptive efficiency, and a spiral valve is one method of increasing its absorption surface.

 

Sharks, rays, chimaeras, lungfishes, surviving chondrosteans, holosteans, and even a few of the more primitive teleosts have a spiral valve or at least traces of it in the intestine. Most modern teleosts have increased the area of the intestinal walls by having numerous folds and villi (fingerlike projections) somewhat like those in humans. Undigested substances are passed to the exterior through the anus in most teleost fishes. In lungfishes, sharks, and rays, it is first passed through the cloaca, a common cavity receiving the intestinal opening and the ducts from the urogenital system.

 

Oxygen and carbon dioxide dissolve in water, and most fishes exchange dissolved oxygen and carbon dioxide in water by means of the gills. The gills lie behind and to the side of the mouth cavity and consist of fleshy filaments supported by the gill arches and filled with blood vessels, which give gills a bright red colour. Water taken in continuously through the mouth passes backward between the gill bars and over the gill filaments, where the exchange of gases takes place. The gills are protected by a gill cover in teleosts and many other fishes but by flaps of skin in sharks, rays, and some of the older fossil fish groups. The blood capillaries in the gill filaments are close to the gill surface to take up oxygen from the water and to give up excess carbon dioxide to the water.

 

Most modern fishes have a hydrostatic (ballast) organ, called the swim bladder, that lies in the body cavity just below the kidney and above the stomach and intestine. It originated as a diverticulum of the digestive canal. In advanced teleosts, especially the acanthopterygians, the bladder has lost its connection with the digestive tract, a condition called physoclistic. The connection has been retained (physostomous) by many relatively primitive teleosts. In several unrelated lines of fishes, the bladder has become specialized as a lung or, at least, as a highly vascularized accessory breathing organ. Some fishes with such accessory organs are obligate air breathers and will drown if denied access to the surface, even in well-oxygenated water. Fishes with a hydrostatic form of swim bladder can control their depth by regulating the amount of gas in the bladder. The gas, mostly oxygen, is secreted into the bladder by special glands, rendering the fish more buoyant; the gas is absorbed into the bloodstream by another special organ, reducing the overall buoyancy and allowing the fish to sink. Some deep-sea fishes may have oils, rather than gas, in the bladder. Other deep-sea and some bottom-living forms have much-reduced swim bladders or have lost the organ entirely.

 

The swim bladder of fishes follows the same developmental pattern as the lungs of land vertebrates. There is no doubt that the two structures have the same historical origin in primitive fishes. More or less intermediate forms still survive among the more primitive types of fishes, such as the lungfishes Lepidosiren and Protopterus.

 

The circulatory, or blood vascular, system consists of the heart, the arteries, the capillaries, and the veins. It is in the capillaries that the interchange of oxygen, carbon dioxide, nutrients, and other substances such as hormones and waste products takes place. The capillaries lead to the veins, which return the venous blood with its waste products to the heart, kidneys, and gills. There are two kinds of capillary beds: those in the gills and those in the rest of the body. The heart, a folded continuous muscular tube with three or four saclike enlargements, undergoes rhythmic contractions and receives venous blood in a sinus venosus. It passes the blood to an auricle and then into a thick muscular pump, the ventricle. From the ventricle the blood goes to a bulbous structure at the base of a ventral aorta just below the gills. The blood passes to the afferent (receiving) arteries of the gill arches and then to the gill capillaries. There waste gases are given off to the environment, and oxygen is absorbed. The oxygenated blood enters efferent (exuant) arteries of the gill arches and then flows into the dorsal aorta. From there blood is distributed to the tissues and organs of the body. One-way valves prevent backflow. The circulation of fishes thus differs from that of the reptiles, birds, and mammals in that oxygenated blood is not returned to the heart prior to distribution to the other parts of the body.

 

The primary excretory organ in fishes, as in other vertebrates, is the kidney. In fishes some excretion also takes place in the digestive tract, skin, and especially the gills (where ammonia is given off). Compared with land vertebrates, fishes have a special problem in maintaining their internal environment at a constant concentration of water and dissolved substances, such as salts. Proper balance of the internal environment (homeostasis) of a fish is in a great part maintained by the excretory system, especially the kidney.

 

The kidney, gills, and skin play an important role in maintaining a fish’s internal environment and checking the effects of osmosis. Marine fishes live in an environment in which the water around them has a greater concentration of salts than they can have inside their body and still maintain life. Freshwater fishes, on the other hand, live in water with a much lower concentration of salts than they require inside their bodies. Osmosis tends to promote the loss of water from the body of a marine fish and absorption of water by that of a freshwater fish. Mucus in the skin tends to slow the process but is not a sufficient barrier to prevent the movement of fluids through the permeable skin. When solutions on two sides of a permeable membrane have different concentrations of dissolved substances, water will pass through the membrane into the more concentrated solution, while the dissolved chemicals move into the area of lower concentration (diffusion).

 

The kidney of freshwater fishes is often larger in relation to body weight than that of marine fishes. In both groups the kidney excretes wastes from the body, but the kidney of freshwater fishes also excretes large amounts of water, counteracting the water absorbed through the skin. Freshwater fishes tend to lose salt to the environment and must replace it. They get some salt from their food, but the gills and skin inside the mouth actively absorb salt from water passed through the mouth. This absorption is performed by special cells capable of moving salts against the diffusion gradient. Freshwater fishes drink very little water and take in little water with their food.

 

Marine fishes must conserve water, and therefore their kidneys excrete little water. To maintain their water balance, marine fishes drink large quantities of seawater, retaining most of the water and excreting the salt. Most nitrogenous waste in marine fishes appears to be secreted by the gills as ammonia. Marine fishes can excrete salt by clusters of special cells (chloride cells) in the gills.

 

There are several teleosts—for example, the salmon—that travel between fresh water and seawater and must adjust to the reversal of osmotic gradients. They adjust their physiological processes by spending time (often surprisingly little time) in the intermediate brackish environment.

 

Marine hagfishes, sharks, and rays have osmotic concentrations in their blood about equal to that of seawater and so do not have to drink water nor perform much physiological work to maintain their osmotic balance. In sharks and rays the osmotic concentration is kept high by retention of urea in the blood. Freshwater sharks have a lowered concentration of urea in the blood.

 

Endocrine glands secrete their products into the bloodstream and body tissues and, along with the central nervous system, control and regulate many kinds of body functions. Cyclostomes have a well-developed endocrine system, and presumably it was well developed in the early Agnatha, ancestral to modern fishes. Although the endocrine system in fishes is similar to that of higher vertebrates, there are numerous differences in detail. The pituitary, the thyroid, the suprarenals, the adrenals, the pancreatic islets, the sex glands (ovaries and testes), the inner wall of the intestine, and the bodies of the ultimobranchial gland make up the endocrine system in fishes. There are some others whose function is not well understood. These organs regulate sexual activity and reproduction, growth, osmotic pressure, general metabolic activities such as the storage of fat and the utilization of foodstuffs, blood pressure, and certain aspects of skin colour. Many of these activities are also controlled in part by the central nervous system, which works with the endocrine system in maintaining the life of a fish. Some parts of the endocrine system are developmentally, and undoubtedly evolutionarily, derived from the nervous system.

 

As in all vertebrates, the nervous system of fishes is the primary mechanism coordinating body activities, as well as integrating these activities in the appropriate manner with stimuli from the environment. The central nervous system, consisting of the brain and spinal cord, is the primary integrating mechanism. The peripheral nervous system, consisting of nerves that connect the brain and spinal cord to various body organs, carries sensory information from special receptor organs such as the eyes, internal ears, nares (sense of smell), taste glands, and others to the integrating centres of the brain and spinal cord. The peripheral nervous system also carries information via different nerve cells from the integrating centres of the brain and spinal cord. This coded information is carried to the various organs and body systems, such as the skeletal muscular system, for appropriate action in response to the original external or internal stimulus. Another branch of the nervous system, the autonomic nervous system, helps to coordinate the activities of many glands and organs and is itself closely connected to the integrating centres of the brain.

 

The brain of the fish is divided into several anatomical and functional parts, all closely interconnected but each serving as the primary centre of integrating particular kinds of responses and activities. Several of these centres or parts are primarily associated with one type of sensory perception, such as sight, hearing, or smell (olfaction).

 

The sense of smell is important in almost all fishes. Certain eels with tiny eyes depend mostly on smell for location of food. The olfactory, or nasal, organ of fishes is located on the dorsal surface of the snout. The lining of the nasal organ has special sensory cells that perceive chemicals dissolved in the water, such as substances from food material, and send sensory information to the brain by way of the first cranial nerve. Odour also serves as an alarm system. Many fishes, especially various species of freshwater minnows, react with alarm to a chemical released from the skin of an injured member of their own species.

 

Many fishes have a well-developed sense of taste, and tiny pitlike taste buds or organs are located not only within their mouth cavities but also over their heads and parts of their body. Catfishes, which often have poor vision, have barbels (“whiskers”) that serve as supplementary taste organs, those around the mouth being actively used to search out food on the bottom. Some species of naturally blind cave fishes are especially well supplied with taste buds, which often cover most of their body surface.

 

Sight is extremely important in most fishes. The eye of a fish is basically like that of all other vertebrates, but the eyes of fishes are extremely varied in structure and adaptation. In general, fishes living in dark and dim water habitats have large eyes, unless they have specialized in some compensatory way so that another sense (such as smell) is dominant, in which case the eyes will often be reduced. Fishes living in brightly lighted shallow waters often will have relatively small but efficient eyes. Cyclostomes have somewhat less elaborate eyes than other fishes, with skin stretched over the eyeball perhaps making their vision somewhat less effective. Most fishes have a spherical lens and accommodate their vision to far or near subjects by moving the lens within the eyeball. A few sharks accommodate by changing the shape of the lens, as in land vertebrates. Those fishes that are heavily dependent upon the eyes have especially strong muscles for accommodation. Most fishes see well, despite the restrictions imposed by frequent turbidity of the water and by light refraction.

 

Fossil evidence suggests that colour vision evolved in fishes more than 300 million years ago, but not all living fishes have retained this ability. Experimental evidence indicates that many shallow-water fishes, if not all, have colour vision and see some colours especially well, but some bottom-dwelling shore fishes live in areas where the water is sufficiently deep to filter out most if not all colours, and these fishes apparently never see colours. When tested in shallow water, they apparently are unable to respond to colour differences.

 

Sound perception and balance are intimately associated senses in a fish. The organs of hearing are entirely internal, located within the skull, on each side of the brain and somewhat behind the eyes. Sound waves, especially those of low frequencies, travel readily through water and impinge directly upon the bones and fluids of the head and body, to be transmitted to the hearing organs. Fishes readily respond to sound; for example, a trout conditioned to escape by the approach of fishermen will take flight upon perceiving footsteps on a stream bank even if it cannot see a fisherman. Compared with humans, however, the range of sound frequencies heard by fishes is greatly restricted. Many fishes communicate with each other by producing sounds in their swim bladders, in their throats by rasping their teeth, and in other ways.

 

A fish or other vertebrate seldom has to rely on a single type of sensory information to determine the nature of the environment around it. A catfish uses taste and touch when examining a food object with its oral barbels. Like most other animals, fishes have many touch receptors over their body surface. Pain and temperature receptors also are present in fishes and presumably produce the same kind of information to a fish as to humans. Fishes react in a negative fashion to stimuli that would be painful to human beings, suggesting that they feel a sensation of pain.

 

An important sensory system in fishes that is absent in other vertebrates (except some amphibians) is the lateral line system. This consists of a series of heavily innervated small canals located in the skin and bone around the eyes, along the lower jaw, over the head, and down the mid-side of the body, where it is associated with the scales. Intermittently along these canals are located tiny sensory organs (pit organs) that apparently detect changes in pressure. The system allows a fish to sense changes in water currents and pressure, thereby helping the fish to orient itself to the various changes that occur in the physical environment.

  

Fish, any of approximately 34,000 species of vertebrate animals (phylum Chordata) found in the fresh and salt waters of the world. Living species range from the primitive jawless lampreys and hagfishes through the cartilaginous sharks, skates, and rays to the abundant and diverse bony fishes. Most fish species are cold-blooded; however, one species, the opah (Lampris guttatus), is warm-blooded.

 

The term fish is applied to a variety of vertebrates of several evolutionary lines. It describes a life-form rather than a taxonomic group. As members of the phylum Chordata, fish share certain features with other vertebrates. These features are gill slits at some point in the life cycle, a notochord, or skeletal supporting rod, a dorsal hollow nerve cord, and a tail. Living fishes represent some five classes, which are as distinct from one another as are the four classes of familiar air-breathing animals—amphibians, reptiles, birds, and mammals. For example, the jawless fishes (Agnatha) have gills in pouches and lack limb girdles. Extant agnathans are the lampreys and the hagfishes. As the name implies, the skeletons of fishes of the class Chondrichthyes (from chondr, “cartilage,” and ichthyes, “fish”) are made entirely of cartilage. Modern fish of this class lack a swim bladder, and their scales and teeth are made up of the same placoid material. Sharks, skates, and rays are examples of cartilaginous fishes. The bony fishes are by far the largest class. Examples range from the tiny seahorse to the 450-kg (1,000-pound) blue marlin, from the flattened soles and flounders to the boxy puffers and ocean sunfishes. Unlike the scales of the cartilaginous fishes, those of bony fishes, when present, grow throughout life and are made up of thin overlapping plates of bone. Bony fishes also have an operculum that covers the gill slits.

 

The study of fishes, the science of ichthyology, is of broad importance. Fishes are of interest to humans for many reasons, the most important being their relationship with and dependence on the environment. A more obvious reason for interest in fishes is their role as a moderate but important part of the world’s food supply. This resource, once thought unlimited, is now realized to be finite and in delicate balance with the biological, chemical, and physical factors of the aquatic environment. Overfishing, pollution, and alteration of the environment are the chief enemies of proper fisheries management, both in fresh waters and in the ocean. (For a detailed discussion of the technology and economics of fisheries, see commercial fishing.) Another practical reason for studying fishes is their use in disease control. As predators on mosquito larvae, they help curb malaria and other mosquito-borne diseases.

 

Fishes are valuable laboratory animals in many aspects of medical and biological research. For example, the readiness of many fishes to acclimate to captivity has allowed biologists to study behaviour, physiology, and even ecology under relatively natural conditions. Fishes have been especially important in the study of animal behaviour, where research on fishes has provided a broad base for the understanding of the more flexible behaviour of the higher vertebrates. The zebra fish is used as a model in studies of gene expression.

 

There are aesthetic and recreational reasons for an interest in fishes. Millions of people keep live fishes in home aquariums for the simple pleasure of observing the beauty and behaviour of animals otherwise unfamiliar to them. Aquarium fishes provide a personal challenge to many aquarists, allowing them to test their ability to keep a small section of the natural environment in their homes. Sportfishing is another way of enjoying the natural environment, also indulged in by millions of people every year. Interest in aquarium fishes and sportfishing supports multimillion-dollar industries throughout the world.

 

Fishes have been in existence for more than 450 million years, during which time they have evolved repeatedly to fit into almost every conceivable type of aquatic habitat. In a sense, land vertebrates are simply highly modified fishes: when fishes colonized the land habitat, they became tetrapod (four-legged) land vertebrates. The popular conception of a fish as a slippery, streamlined aquatic animal that possesses fins and breathes by gills applies to many fishes, but far more fishes deviate from that conception than conform to it. For example, the body is elongate in many forms and greatly shortened in others; the body is flattened in some (principally in bottom-dwelling fishes) and laterally compressed in many others; the fins may be elaborately extended, forming intricate shapes, or they may be reduced or even lost; and the positions of the mouth, eyes, nostrils, and gill openings vary widely. Air breathers have appeared in several evolutionary lines.

 

Many fishes are cryptically coloured and shaped, closely matching their respective environments; others are among the most brilliantly coloured of all organisms, with a wide range of hues, often of striking intensity, on a single individual. The brilliance of pigments may be enhanced by the surface structure of the fish, so that it almost seems to glow. A number of unrelated fishes have actual light-producing organs. Many fishes are able to alter their coloration—some for the purpose of camouflage, others for the enhancement of behavioral signals.

 

Fishes range in adult length from less than 10 mm (0.4 inch) to more than 20 metres (60 feet) and in weight from about 1.5 grams (less than 0.06 ounce) to many thousands of kilograms. Some live in shallow thermal springs at temperatures slightly above 42 °C (100 °F), others in cold Arctic seas a few degrees below 0 °C (32 °F) or in cold deep waters more than 4,000 metres (13,100 feet) beneath the ocean surface. The structural and, especially, the physiological adaptations for life at such extremes are relatively poorly known and provide the scientifically curious with great incentive for study.

 

Almost all natural bodies of water bear fish life, the exceptions being very hot thermal ponds and extremely salt-alkaline lakes, such as the Dead Sea in Asia and the Great Salt Lake in North America. The present distribution of fishes is a result of the geological history and development of Earth as well as the ability of fishes to undergo evolutionary change and to adapt to the available habitats. Fishes may be seen to be distributed according to habitat and according to geographical area. Major habitat differences are marine and freshwater. For the most part, the fishes in a marine habitat differ from those in a freshwater habitat, even in adjacent areas, but some, such as the salmon, migrate from one to the other. The freshwater habitats may be seen to be of many kinds. Fishes found in mountain torrents, Arctic lakes, tropical lakes, temperate streams, and tropical rivers will all differ from each other, both in obvious gross structure and in physiological attributes. Even in closely adjacent habitats where, for example, a tropical mountain torrent enters a lowland stream, the fish fauna will differ. The marine habitats can be divided into deep ocean floors (benthic), mid-water oceanic (bathypelagic), surface oceanic (pelagic), rocky coast, sandy coast, muddy shores, bays, estuaries, and others. Also, for example, rocky coastal shores in tropical and temperate regions will have different fish faunas, even when such habitats occur along the same coastline.

 

Although much is known about the present geographical distribution of fishes, far less is known about how that distribution came about. Many parts of the fish fauna of the fresh waters of North America and Eurasia are related and undoubtedly have a common origin. The faunas of Africa and South America are related, extremely old, and probably an expression of the drifting apart of the two continents. The fauna of southern Asia is related to that of Central Asia, and some of it appears to have entered Africa. The extremely large shore-fish faunas of the Indian and tropical Pacific oceans comprise a related complex, but the tropical shore fauna of the Atlantic, although containing Indo-Pacific components, is relatively limited and probably younger. The Arctic and Antarctic marine faunas are quite different from each other. The shore fauna of the North Pacific is quite distinct, and that of the North Atlantic more limited and probably younger. Pelagic oceanic fishes, especially those in deep waters, are similar the world over, showing little geographical isolation in terms of family groups. The deep oceanic habitat is very much the same throughout the world, but species differences do exist, showing geographical areas determined by oceanic currents and water masses.

 

All aspects of the life of a fish are closely correlated with adaptation to the total environment, physical, chemical, and biological. In studies, all the interdependent aspects of fish, such as behaviour, locomotion, reproduction, and physical and physiological characteristics, must be taken into account.

 

Correlated with their adaptation to an extremely wide variety of habitats is the extremely wide variety of life cycles that fishes display. The great majority hatch from relatively small eggs a few days to several weeks or more after the eggs are scattered in the water. Newly hatched young are still partially undeveloped and are called larvae until body structures such as fins, skeleton, and some organs are fully formed. Larval life is often very short, usually less than a few weeks, but it can be very long, some lampreys continuing as larvae for at least five years. Young and larval fishes, before reaching sexual maturity, must grow considerably, and their small size and other factors often dictate that they live in a habitat different than that of the adults. For example, most tropical marine shore fishes have pelagic larvae. Larval food also is different, and larval fishes often live in shallow waters, where they may be less exposed to predators.

 

After a fish reaches adult size, the length of its life is subject to many factors, such as innate rates of aging, predation pressure, and the nature of the local climate. The longevity of a species in the protected environment of an aquarium may have nothing to do with how long members of that species live in the wild. Many small fishes live only one to three years at the most. In some species, however, individuals may live as long as 10 or 20 or even 100 years.

 

Fish behaviour is a complicated and varied subject. As in almost all animals with a central nervous system, the nature of a response of an individual fish to stimuli from its environment depends upon the inherited characteristics of its nervous system, on what it has learned from past experience, and on the nature of the stimuli. Compared with the variety of human responses, however, that of a fish is stereotyped, not subject to much modification by “thought” or learning, and investigators must guard against anthropomorphic interpretations of fish behaviour.

 

Fishes perceive the world around them by the usual senses of sight, smell, hearing, touch, and taste and by special lateral line water-current detectors. In the few fishes that generate electric fields, a process that might best be called electrolocation aids in perception. One or another of these senses often is emphasized at the expense of others, depending upon the fish’s other adaptations. In fishes with large eyes, the sense of smell may be reduced; others, with small eyes, hunt and feed primarily by smell (such as some eels).

 

Specialized behaviour is primarily concerned with the three most important activities in the fish’s life: feeding, reproduction, and escape from enemies. Schooling behaviour of sardines on the high seas, for instance, is largely a protective device to avoid enemies, but it is also associated with and modified by their breeding and feeding requirements. Predatory fishes are often solitary, lying in wait to dart suddenly after their prey, a kind of locomotion impossible for beaked parrot fishes, which feed on coral, swimming in small groups from one coral head to the next. In addition, some predatory fishes that inhabit pelagic environments, such as tunas, often school.

 

Sleep in fishes, all of which lack true eyelids, consists of a seemingly listless state in which the fish maintains its balance but moves slowly. If attacked or disturbed, most can dart away. A few kinds of fishes lie on the bottom to sleep. Most catfishes, some loaches, and some eels and electric fishes are strictly nocturnal, being active and hunting for food during the night and retiring during the day to holes, thick vegetation, or other protective parts of the environment.

 

Communication between members of a species or between members of two or more species often is extremely important, especially in breeding behaviour (see below Reproduction). The mode of communication may be visual, as between the small so-called cleaner fish and a large fish of a very different species. The larger fish often allows the cleaner to enter its mouth to remove gill parasites. The cleaner is recognized by its distinctive colour and actions and therefore is not eaten, even if the larger fish is normally a predator. Communication is often chemical, signals being sent by specific chemicals called pheromones.

 

Many fishes have a streamlined body and swim freely in open water. Fish locomotion is closely correlated with habitat and ecological niche (the general position of the animal to its environment).

 

Many fishes in both marine and fresh waters swim at the surface and have mouths adapted to feed best (and sometimes only) at the surface. Often such fishes are long and slender, able to dart at surface insects or at other surface fishes and in turn to dart away from predators; needlefishes, halfbeaks, and topminnows (such as killifish and mosquito fish) are good examples. Oceanic flying fishes escape their predators by gathering speed above the water surface, with the lower lobe of the tail providing thrust in the water. They then glide hundreds of yards on enlarged, winglike pectoral and pelvic fins. South American freshwater flying fishes escape their enemies by jumping and propelling their strongly keeled bodies out of the water.

 

So-called mid-water swimmers, the most common type of fish, are of many kinds and live in many habitats. The powerful fusiform tunas and the trouts, for example, are adapted for strong, fast swimming, the tunas to capture prey speedily in the open ocean and the trouts to cope with the swift currents of streams and rivers. The trout body form is well adapted to many habitats. Fishes that live in relatively quiet waters such as bays or lake shores or slow rivers usually are not strong, fast swimmers but are capable of short, quick bursts of speed to escape a predator. Many of these fishes have their sides flattened, examples being the sunfish and the freshwater angelfish of aquarists. Fish associated with the bottom or substrate usually are slow swimmers. Open-water plankton-feeding fishes almost always remain fusiform and are capable of rapid, strong movement (for example, sardines and herrings of the open ocean and also many small minnows of streams and lakes).

 

Bottom-living fishes are of many kinds and have undergone many types of modification of their body shape and swimming habits. Rays, which evolved from strong-swimming mid-water sharks, usually stay close to the bottom and move by undulating their large pectoral fins. Flounders live in a similar habitat and move over the bottom by undulating the entire body. Many bottom fishes dart from place to place, resting on the bottom between movements, a motion common in gobies. One goby relative, the mudskipper, has taken to living at the edge of pools along the shore of muddy mangrove swamps. It escapes its enemies by flipping rapidly over the mud, out of the water. Some catfishes, synbranchid eels, the so-called climbing perch, and a few other fishes venture out over damp ground to find more promising waters than those that they left. They move by wriggling their bodies, sometimes using strong pectoral fins; most have accessory air-breathing organs. Many bottom-dwelling fishes live in mud holes or rocky crevices. Marine eels and gobies commonly are found in such habitats and for the most part venture far beyond their cavelike homes. Some bottom dwellers, such as the clingfishes (Gobiesocidae), have developed powerful adhesive disks that enable them to remain in place on the substrate in areas such as rocky coasts, where the action of the waves is great.

 

The methods of reproduction in fishes are varied, but most fishes lay a large number of small eggs, fertilized and scattered outside of the body. The eggs of pelagic fishes usually remain suspended in the open water. Many shore and freshwater fishes lay eggs on the bottom or among plants. Some have adhesive eggs. The mortality of the young and especially of the eggs is very high, and often only a few individuals grow to maturity out of hundreds, thousands, and in some cases millions of eggs laid.

 

Males produce sperm, usually as a milky white substance called milt, in two (sometimes one) testes within the body cavity. In bony fishes a sperm duct leads from each testis to a urogenital opening behind the vent or anus. In sharks and rays and in cyclostomes the duct leads to a cloaca. Sometimes the pelvic fins are modified to help transmit the milt to the eggs at the female’s vent or on the substrate where the female has placed them. Sometimes accessory organs are used to fertilize females internally—for example, the claspers of many sharks and rays.

 

In the females the eggs are formed in two ovaries (sometimes only one) and pass through the ovaries to the urogenital opening and to the outside. In some fishes the eggs are fertilized internally but are shed before development takes place. Members of about a dozen families each of bony fishes (teleosts) and sharks bear live young. Many skates and rays also bear live young. In some bony fishes the eggs simply develop within the female, the young emerging when the eggs hatch (ovoviviparous). Others develop within the ovary and are nourished by ovarian tissues after hatching (viviparous). There are also other methods utilized by fishes to nourish young within the female. In all live-bearers the young are born at a relatively large size and are few in number. In one family of primarily marine fishes, the surfperches from the Pacific coast of North America, Japan, and Korea, the males of at least one species are born sexually mature, although they are not fully grown.

 

Some fishes are hermaphroditic—an individual producing both sperm and eggs, usually at different stages of its life. Self-fertilization, however, is probably rare.

 

Successful reproduction and, in many cases, defense of the eggs and the young are assured by rather stereotypical but often elaborate courtship and parental behaviour, either by the male or the female or both. Some fishes prepare nests by hollowing out depressions in the sand bottom (cichlids, for example), build nests with plant materials and sticky threads excreted by the kidneys (sticklebacks), or blow a cluster of mucus-covered bubbles at the water surface (gouramis). The eggs are laid in these structures. Some varieties of cichlids and catfishes incubate eggs in their mouths.

 

Some fishes, such as salmon, undergo long migrations from the ocean and up large rivers to spawn in the gravel beds where they themselves hatched (anadromous fishes). Some, such as the freshwater eels (family Anguillidae), live and grow to maturity in fresh water and migrate to the sea to spawn (catadromous fishes). Other fishes undertake shorter migrations from lakes into streams, within the ocean, or enter spawning habitats that they do not ordinarily occupy in other ways.

 

The basic structure and function of the fish body are similar to those of all other vertebrates. The usual four types of tissues are present: surface or epithelial, connective (bone, cartilage, and fibrous tissues, as well as their derivative, blood), nerve, and muscle tissues. In addition, the fish’s organs and organ systems parallel those of other vertebrates.

 

The typical fish body is streamlined and spindle-shaped, with an anterior head, a gill apparatus, and a heart, the latter lying in the midline just below the gill chamber. The body cavity, containing the vital organs, is situated behind the head in the lower anterior part of the body. The anus usually marks the posterior termination of the body cavity and most often occurs just in front of the base of the anal fin. The spinal cord and vertebral column continue from the posterior part of the head to the base of the tail fin, passing dorsal to the body cavity and through the caudal (tail) region behind the body cavity. Most of the body is of muscular tissue, a high proportion of which is necessitated by swimming. In the course of evolution this basic body plan has been modified repeatedly into the many varieties of fish shapes that exist today.

 

The skeleton forms an integral part of the fish’s locomotion system, as well as serving to protect vital parts. The internal skeleton consists of the skull bones (except for the roofing bones of the head, which are really part of the external skeleton), the vertebral column, and the fin supports (fin rays). The fin supports are derived from the external skeleton but will be treated here because of their close functional relationship to the internal skeleton. The internal skeleton of cyclostomes, sharks, and rays is of cartilage; that of many fossil groups and some primitive living fishes is mostly of cartilage but may include some bone. In place of the vertebral column, the earliest vertebrates had a fully developed notochord, a flexible stiff rod of viscous cells surrounded by a strong fibrous sheath. During the evolution of modern fishes the rod was replaced in part by cartilage and then by ossified cartilage. Sharks and rays retain a cartilaginous vertebral column; bony fishes have spool-shaped vertebrae that in the more primitive living forms only partially replace the notochord. The skull, including the gill arches and jaws of bony fishes, is fully, or at least partially, ossified. That of sharks and rays remains cartilaginous, at times partially replaced by calcium deposits but never by true bone.

 

The supportive elements of the fins (basal or radial bones or both) have changed greatly during fish evolution. Some of these changes are described in the section below (Evolution and paleontology). Most fishes possess a single dorsal fin on the midline of the back. Many have two and a few have three dorsal fins. The other fins are the single tail and anal fins and paired pelvic and pectoral fins. A small fin, the adipose fin, with hairlike fin rays, occurs in many of the relatively primitive teleosts (such as trout) on the back near the base of the caudal fin.

 

The skin of a fish must serve many functions. It aids in maintaining the osmotic balance, provides physical protection for the body, is the site of coloration, contains sensory receptors, and, in some fishes, functions in respiration. Mucous glands, which aid in maintaining the water balance and offer protection from bacteria, are extremely numerous in fish skin, especially in cyclostomes and teleosts. Since mucous glands are present in the modern lampreys, it is reasonable to assume that they were present in primitive fishes, such as the ancient Silurian and Devonian agnathans. Protection from abrasion and predation is another function of the fish skin, and dermal (skin) bone arose early in fish evolution in response to this need. It is thought that bone first evolved in skin and only later invaded the cartilaginous areas of the fish’s body, to provide additional support and protection. There is some argument as to which came first, cartilage or bone, and fossil evidence does not settle the question. In any event, dermal bone has played an important part in fish evolution and has different characteristics in different groups of fishes. Several groups are characterized at least in part by the kind of bony scales they possess.

 

Scales have played an important part in the evolution of fishes. Primitive fishes usually had thick bony plates or thick scales in several layers of bone, enamel, and related substances. Modern teleost fishes have scales of bone, which, while still protective, allow much more freedom of motion in the body. A few modern teleosts (some catfishes, sticklebacks, and others) have secondarily acquired bony plates in the skin. Modern and early sharks possessed placoid scales, a relatively primitive type of scale with a toothlike structure, consisting of an outside layer of enamel-like substance (vitrodentine), an inner layer of dentine, and a pulp cavity containing nerves and blood vessels. Primitive bony fishes had thick scales of either the ganoid or the cosmoid type. Cosmoid scales have a hard, enamel-like outer layer, an inner layer of cosmine (a form of dentine), and then a layer of vascular bone (isopedine). In ganoid scales the hard outer layer is different chemically and is called ganoin. Under this is a cosminelike layer and then a vascular bony layer. The thin, translucent bony scales of modern fishes, called cycloid and ctenoid (the latter distinguished by serrations at the edges), lack enameloid and dentine layers.

 

Skin has several other functions in fishes. It is well supplied with nerve endings and presumably receives tactile, thermal, and pain stimuli. Skin is also well supplied with blood vessels. Some fishes breathe in part through the skin, by the exchange of oxygen and carbon dioxide between the surrounding water and numerous small blood vessels near the skin surface.

 

Skin serves as protection through the control of coloration. Fishes exhibit an almost limitless range of colours. The colours often blend closely with the surroundings, effectively hiding the animal. Many fishes use bright colours for territorial advertisement or as recognition marks for other members of their own species, or sometimes for members of other species. Many fishes can change their colour to a greater or lesser degree, by movement of pigment within the pigment cells (chromatophores). Black pigment cells (melanophores), of almost universal occurrence in fishes, are often juxtaposed with other pigment cells. When placed beneath iridocytes or leucophores (bearing the silvery or white pigment guanine), melanophores produce structural colours of blue and green. These colours are often extremely intense, because they are formed by refraction of light through the needlelike crystals of guanine. The blue and green refracted colours are often relatively pure, lacking the red and yellow rays, which have been absorbed by the black pigment (melanin) of the melanophores. Yellow, orange, and red colours are produced by erythrophores, cells containing the appropriate carotenoid pigments. Other colours are produced by combinations of melanophores, erythrophores, and iridocytes.

 

The major portion of the body of most fishes consists of muscles. Most of the mass is trunk musculature, the fin muscles usually being relatively small. The caudal fin is usually the most powerful fin, being moved by the trunk musculature. The body musculature is usually arranged in rows of chevron-shaped segments on each side. Contractions of these segments, each attached to adjacent vertebrae and vertebral processes, bends the body on the vertebral joint, producing successive undulations of the body, passing from the head to the tail, and producing driving strokes of the tail. It is the latter that provides the strong forward movement for most fishes.

 

The digestive system, in a functional sense, starts at the mouth, with the teeth used to capture prey or collect plant foods. Mouth shape and tooth structure vary greatly in fishes, depending on the kind of food normally eaten. Most fishes are predacious, feeding on small invertebrates or other fishes and have simple conical teeth on the jaws, on at least some of the bones of the roof of the mouth, and on special gill arch structures just in front of the esophagus. The latter are throat teeth. Most predacious fishes swallow their prey whole, and the teeth are used for grasping and holding prey, for orienting prey to be swallowed (head first) and for working the prey toward the esophagus. There are a variety of tooth types in fishes. Some fishes, such as sharks and piranhas, have cutting teeth for biting chunks out of their victims. A shark’s tooth, although superficially like that of a piranha, appears in many respects to be a modified scale, while that of the piranha is like that of other bony fishes, consisting of dentine and enamel. Parrot fishes have beaklike mouths with short incisor-like teeth for breaking off coral and have heavy pavementlike throat teeth for crushing the coral. Some catfishes have small brushlike teeth, arranged in rows on the jaws, for scraping plant and animal growth from rocks. Many fishes (such as the Cyprinidae or minnows) have no jaw teeth at all but have very strong throat teeth.

 

Some fishes gather planktonic food by straining it from their gill cavities with numerous elongate stiff rods (gill rakers) anchored by one end to the gill bars. The food collected on these rods is passed to the throat, where it is swallowed. Most fishes have only short gill rakers that help keep food particles from escaping out the mouth cavity into the gill chamber.

 

Once reaching the throat, food enters a short, often greatly distensible esophagus, a simple tube with a muscular wall leading into a stomach. The stomach varies greatly in fishes, depending upon the diet. In most predacious fishes it is a simple straight or curved tube or pouch with a muscular wall and a glandular lining. Food is largely digested there and leaves the stomach in liquid form.

 

Between the stomach and the intestine, ducts enter the digestive tube from the liver and pancreas. The liver is a large, clearly defined organ. The pancreas may be embedded in it, diffused through it, or broken into small parts spread along some of the intestine. The junction between the stomach and the intestine is marked by a muscular valve. Pyloric ceca (blind sacs) occur in some fishes at this junction and have a digestive or absorptive function or both.

 

The intestine itself is quite variable in length, depending upon the fish’s diet. It is short in predacious forms, sometimes no longer than the body cavity, but long in herbivorous forms, being coiled and several times longer than the entire length of the fish in some species of South American catfishes. The intestine is primarily an organ for absorbing nutrients into the bloodstream. The larger its internal surface, the greater its absorptive efficiency, and a spiral valve is one method of increasing its absorption surface.

 

Sharks, rays, chimaeras, lungfishes, surviving chondrosteans, holosteans, and even a few of the more primitive teleosts have a spiral valve or at least traces of it in the intestine. Most modern teleosts have increased the area of the intestinal walls by having numerous folds and villi (fingerlike projections) somewhat like those in humans. Undigested substances are passed to the exterior through the anus in most teleost fishes. In lungfishes, sharks, and rays, it is first passed through the cloaca, a common cavity receiving the intestinal opening and the ducts from the urogenital system.

 

Oxygen and carbon dioxide dissolve in water, and most fishes exchange dissolved oxygen and carbon dioxide in water by means of the gills. The gills lie behind and to the side of the mouth cavity and consist of fleshy filaments supported by the gill arches and filled with blood vessels, which give gills a bright red colour. Water taken in continuously through the mouth passes backward between the gill bars and over the gill filaments, where the exchange of gases takes place. The gills are protected by a gill cover in teleosts and many other fishes but by flaps of skin in sharks, rays, and some of the older fossil fish groups. The blood capillaries in the gill filaments are close to the gill surface to take up oxygen from the water and to give up excess carbon dioxide to the water.

 

Most modern fishes have a hydrostatic (ballast) organ, called the swim bladder, that lies in the body cavity just below the kidney and above the stomach and intestine. It originated as a diverticulum of the digestive canal. In advanced teleosts, especially the acanthopterygians, the bladder has lost its connection with the digestive tract, a condition called physoclistic. The connection has been retained (physostomous) by many relatively primitive teleosts. In several unrelated lines of fishes, the bladder has become specialized as a lung or, at least, as a highly vascularized accessory breathing organ. Some fishes with such accessory organs are obligate air breathers and will drown if denied access to the surface, even in well-oxygenated water. Fishes with a hydrostatic form of swim bladder can control their depth by regulating the amount of gas in the bladder. The gas, mostly oxygen, is secreted into the bladder by special glands, rendering the fish more buoyant; the gas is absorbed into the bloodstream by another special organ, reducing the overall buoyancy and allowing the fish to sink. Some deep-sea fishes may have oils, rather than gas, in the bladder. Other deep-sea and some bottom-living forms have much-reduced swim bladders or have lost the organ entirely.

 

The swim bladder of fishes follows the same developmental pattern as the lungs of land vertebrates. There is no doubt that the two structures have the same historical origin in primitive fishes. More or less intermediate forms still survive among the more primitive types of fishes, such as the lungfishes Lepidosiren and Protopterus.

 

The circulatory, or blood vascular, system consists of the heart, the arteries, the capillaries, and the veins. It is in the capillaries that the interchange of oxygen, carbon dioxide, nutrients, and other substances such as hormones and waste products takes place. The capillaries lead to the veins, which return the venous blood with its waste products to the heart, kidneys, and gills. There are two kinds of capillary beds: those in the gills and those in the rest of the body. The heart, a folded continuous muscular tube with three or four saclike enlargements, undergoes rhythmic contractions and receives venous blood in a sinus venosus. It passes the blood to an auricle and then into a thick muscular pump, the ventricle. From the ventricle the blood goes to a bulbous structure at the base of a ventral aorta just below the gills. The blood passes to the afferent (receiving) arteries of the gill arches and then to the gill capillaries. There waste gases are given off to the environment, and oxygen is absorbed. The oxygenated blood enters efferent (exuant) arteries of the gill arches and then flows into the dorsal aorta. From there blood is distributed to the tissues and organs of the body. One-way valves prevent backflow. The circulation of fishes thus differs from that of the reptiles, birds, and mammals in that oxygenated blood is not returned to the heart prior to distribution to the other parts of the body.

 

The primary excretory organ in fishes, as in other vertebrates, is the kidney. In fishes some excretion also takes place in the digestive tract, skin, and especially the gills (where ammonia is given off). Compared with land vertebrates, fishes have a special problem in maintaining their internal environment at a constant concentration of water and dissolved substances, such as salts. Proper balance of the internal environment (homeostasis) of a fish is in a great part maintained by the excretory system, especially the kidney.

 

The kidney, gills, and skin play an important role in maintaining a fish’s internal environment and checking the effects of osmosis. Marine fishes live in an environment in which the water around them has a greater concentration of salts than they can have inside their body and still maintain life. Freshwater fishes, on the other hand, live in water with a much lower concentration of salts than they require inside their bodies. Osmosis tends to promote the loss of water from the body of a marine fish and absorption of water by that of a freshwater fish. Mucus in the skin tends to slow the process but is not a sufficient barrier to prevent the movement of fluids through the permeable skin. When solutions on two sides of a permeable membrane have different concentrations of dissolved substances, water will pass through the membrane into the more concentrated solution, while the dissolved chemicals move into the area of lower concentration (diffusion).

 

The kidney of freshwater fishes is often larger in relation to body weight than that of marine fishes. In both groups the kidney excretes wastes from the body, but the kidney of freshwater fishes also excretes large amounts of water, counteracting the water absorbed through the skin. Freshwater fishes tend to lose salt to the environment and must replace it. They get some salt from their food, but the gills and skin inside the mouth actively absorb salt from water passed through the mouth. This absorption is performed by special cells capable of moving salts against the diffusion gradient. Freshwater fishes drink very little water and take in little water with their food.

 

Marine fishes must conserve water, and therefore their kidneys excrete little water. To maintain their water balance, marine fishes drink large quantities of seawater, retaining most of the water and excreting the salt. Most nitrogenous waste in marine fishes appears to be secreted by the gills as ammonia. Marine fishes can excrete salt by clusters of special cells (chloride cells) in the gills.

 

There are several teleosts—for example, the salmon—that travel between fresh water and seawater and must adjust to the reversal of osmotic gradients. They adjust their physiological processes by spending time (often surprisingly little time) in the intermediate brackish environment.

 

Marine hagfishes, sharks, and rays have osmotic concentrations in their blood about equal to that of seawater and so do not have to drink water nor perform much physiological work to maintain their osmotic balance. In sharks and rays the osmotic concentration is kept high by retention of urea in the blood. Freshwater sharks have a lowered concentration of urea in the blood.

 

Endocrine glands secrete their products into the bloodstream and body tissues and, along with the central nervous system, control and regulate many kinds of body functions. Cyclostomes have a well-developed endocrine system, and presumably it was well developed in the early Agnatha, ancestral to modern fishes. Although the endocrine system in fishes is similar to that of higher vertebrates, there are numerous differences in detail. The pituitary, the thyroid, the suprarenals, the adrenals, the pancreatic islets, the sex glands (ovaries and testes), the inner wall of the intestine, and the bodies of the ultimobranchial gland make up the endocrine system in fishes. There are some others whose function is not well understood. These organs regulate sexual activity and reproduction, growth, osmotic pressure, general metabolic activities such as the storage of fat and the utilization of foodstuffs, blood pressure, and certain aspects of skin colour. Many of these activities are also controlled in part by the central nervous system, which works with the endocrine system in maintaining the life of a fish. Some parts of the endocrine system are developmentally, and undoubtedly evolutionarily, derived from the nervous system.

 

As in all vertebrates, the nervous system of fishes is the primary mechanism coordinating body activities, as well as integrating these activities in the appropriate manner with stimuli from the environment. The central nervous system, consisting of the brain and spinal cord, is the primary integrating mechanism. The peripheral nervous system, consisting of nerves that connect the brain and spinal cord to various body organs, carries sensory information from special receptor organs such as the eyes, internal ears, nares (sense of smell), taste glands, and others to the integrating centres of the brain and spinal cord. The peripheral nervous system also carries information via different nerve cells from the integrating centres of the brain and spinal cord. This coded information is carried to the various organs and body systems, such as the skeletal muscular system, for appropriate action in response to the original external or internal stimulus. Another branch of the nervous system, the autonomic nervous system, helps to coordinate the activities of many glands and organs and is itself closely connected to the integrating centres of the brain.

 

The brain of the fish is divided into several anatomical and functional parts, all closely interconnected but each serving as the primary centre of integrating particular kinds of responses and activities. Several of these centres or parts are primarily associated with one type of sensory perception, such as sight, hearing, or smell (olfaction).

 

The sense of smell is important in almost all fishes. Certain eels with tiny eyes depend mostly on smell for location of food. The olfactory, or nasal, organ of fishes is located on the dorsal surface of the snout. The lining of the nasal organ has special sensory cells that perceive chemicals dissolved in the water, such as substances from food material, and send sensory information to the brain by way of the first cranial nerve. Odour also serves as an alarm system. Many fishes, especially various species of freshwater minnows, react with alarm to a chemical released from the skin of an injured member of their own species.

 

Many fishes have a well-developed sense of taste, and tiny pitlike taste buds or organs are located not only within their mouth cavities but also over their heads and parts of their body. Catfishes, which often have poor vision, have barbels (“whiskers”) that serve as supplementary taste organs, those around the mouth being actively used to search out food on the bottom. Some species of naturally blind cave fishes are especially well supplied with taste buds, which often cover most of their body surface.

 

Sight is extremely important in most fishes. The eye of a fish is basically like that of all other vertebrates, but the eyes of fishes are extremely varied in structure and adaptation. In general, fishes living in dark and dim water habitats have large eyes, unless they have specialized in some compensatory way so that another sense (such as smell) is dominant, in which case the eyes will often be reduced. Fishes living in brightly lighted shallow waters often will have relatively small but efficient eyes. Cyclostomes have somewhat less elaborate eyes than other fishes, with skin stretched over the eyeball perhaps making their vision somewhat less effective. Most fishes have a spherical lens and accommodate their vision to far or near subjects by moving the lens within the eyeball. A few sharks accommodate by changing the shape of the lens, as in land vertebrates. Those fishes that are heavily dependent upon the eyes have especially strong muscles for accommodation. Most fishes see well, despite the restrictions imposed by frequent turbidity of the water and by light refraction.

 

Fossil evidence suggests that colour vision evolved in fishes more than 300 million years ago, but not all living fishes have retained this ability. Experimental evidence indicates that many shallow-water fishes, if not all, have colour vision and see some colours especially well, but some bottom-dwelling shore fishes live in areas where the water is sufficiently deep to filter out most if not all colours, and these fishes apparently never see colours. When tested in shallow water, they apparently are unable to respond to colour differences.

 

Sound perception and balance are intimately associated senses in a fish. The organs of hearing are entirely internal, located within the skull, on each side of the brain and somewhat behind the eyes. Sound waves, especially those of low frequencies, travel readily through water and impinge directly upon the bones and fluids of the head and body, to be transmitted to the hearing organs. Fishes readily respond to sound; for example, a trout conditioned to escape by the approach of fishermen will take flight upon perceiving footsteps on a stream bank even if it cannot see a fisherman. Compared with humans, however, the range of sound frequencies heard by fishes is greatly restricted. Many fishes communicate with each other by producing sounds in their swim bladders, in their throats by rasping their teeth, and in other ways.

 

A fish or other vertebrate seldom has to rely on a single type of sensory information to determine the nature of the environment around it. A catfish uses taste and touch when examining a food object with its oral barbels. Like most other animals, fishes have many touch receptors over their body surface. Pain and temperature receptors also are present in fishes and presumably produce the same kind of information to a fish as to humans. Fishes react in a negative fashion to stimuli that would be painful to human beings, suggesting that they feel a sensation of pain.

 

An important sensory system in fishes that is absent in other vertebrates (except some amphibians) is the lateral line system. This consists of a series of heavily innervated small canals located in the skin and bone around the eyes, along the lower jaw, over the head, and down the mid-side of the body, where it is associated with the scales. Intermittently along these canals are located tiny sensory organs (pit organs) that apparently detect changes in pressure. The system allows a fish to sense changes in water currents and pressure, thereby helping the fish to orient itself to the various changes that occur in the physical environment.

 

Although a great many fossil fishes have been found and described, they represent a tiny portion of the long and complex evolution of fishes, and knowledge of fish evolution remains relatively fragmentary. In the classification presented in this article, fishlike vertebrates are divided into seven categories, the members of each having a different basic structural organization and different physical and physiological adaptations for the problems presented by the environment. The broad basic pattern has been one of successive replacement of older groups by newer, better-adapted groups. One or a few members of a group evolved a basically more efficient means of feeding, breathing, or swimming or several better ways of living. These better-adapted groups then forced the extinction of members of the older group with which they competed for available food, breeding places, or other necessities of life. As the new fishes became well established, some of them evolved further and adapted to other habitats, where they continued to replace members of the old group already there. The process was repeated until all or almost all members of the old group in a variety of habitats had been replaced by members of the newer evolutionary line.

 

The earliest vertebrate fossils of certain relationships are fragments of dermal armour of jawless fishes (superclass Agnatha, order Heterostraci) from the Upper Ordovician Period in North America, about 450 million years in age. Early Ordovician toothlike fragments from the former Soviet Union are less certainly remains of agnathans. It is uncertain whether the North American jawless fishes inhabited shallow coastal marine waters, where their remains became fossilized, or were freshwater vertebrates washed into coastal deposits by stream action.

 

Jawless fishes probably arose from ancient, small, soft-bodied filter-feeding organisms much like and probably also ancestral to the modern sand-dwelling filter feeders, the Cephalochordata (Amphioxus and its relatives). The body in the ancestral animals was probably stiffened by a notochord. Although a vertebrate origin in fresh water is much debated by paleontologists, it is possible that mobility of the body and protection provided by dermal armour arose in response to streamflow in the freshwater environment and to the need to escape from and resist the clawed invertebrate eurypterids that lived in the same waters. Because of the marine distribution of the surviving primitive chordates, however, many paleontologists doubt that the vertebrates arose in fresh water.

 

Heterostracan remains are next found in what appear to be delta deposits in two North American localities of Silurian age. By the close of the Silurian, about 416 million years ago, European heterostracan remains are found in what appear to be delta or coastal deposits. In the Late Silurian of the Baltic area, lagoon or freshwater deposits yield jawless fishes of the order Osteostraci. Somewhat later in the Silurian from the same region, layers contain fragments of jawed acanthodians, the earliest group of jawed vertebrates, and of jawless fishes. These layers lie between marine beds but appear to be washed out from fresh waters of a coastal region.

 

It is evident, therefore, that by the end of the Silurian both jawed and jawless vertebrates were well established and already must have had a long history of development. Yet paleontologists have remains only of specialized forms that cannot have been the ancestors of the placoderms and bony fishes that appear in the next period, the Devonian. No fossils are known of the more primitive ancestors of the agnathans and acanthodians. The extensive marine beds of the Silurian and those of the Ordovician are essentially void of vertebrate history. It is believed that the ancestors of fishlike vertebrates evolved in upland fresh waters, where whatever few and relatively small fossil beds were made probably have been long since eroded away. Remains of the earliest vertebrates may never be found.

 

By the close of the Silurian, all known orders of jawless vertebrates had evolved, except perhaps the modern cyclostomes, which are without the hard parts that ordinarily are preserved as fossils. Cyclostomes were unknown as fossils until 1968, when a lamprey of modern body structure was reported from the Middle Pennsylvanian of Illinois, in deposits more than 300 million years old. Fossil evidence of the four orders of armoured jawless vertebrates is absent from deposits later than the Devonian. Presumably, these vertebrates became extinct at that time, being replaced by the more efficient and probably more aggressive placoderms, acanthodians, selachians (sharks and relatives), and by early bony fishes. Cyclostomes survived probably because early on they evolved from anaspid agnathans and developed a rasping tonguelike structure and a sucking mouth, enabling them to prey on other fishes. With this way of life they apparently had no competition from other fish groups. Cyclostomes, the hagfishes and lampreys, were once thought to be closely related because of the similarity in their suctorial mouths, but it is now understood that the hagfishes, order Myxiniformes, are the most primitive living chordates, and they are classified separately from the lampreys, order Petromyzontiformes.

 

Early jawless vertebrates probably fed on tiny organisms by filter feeding, as do the larvae of their descendants, the modern lampreys. The gill cavity of the early agnathans was large. It is thought that small organisms taken from the bottom by a nibbling action of the mouth, or more certainly by a sucking action through the mouth, were passed into the gill cavity along with water for breathing. Small organisms then were strained out by the gill apparatus and directed to the food canal. The gill apparatus thus evolved as a feeding, as well as a breathing, structure. The head and gills in the agnathans were protected by a heavy dermal armour; the tail region was free, allowing motion for swimming.

 

Most important for the evolution of fishes and vertebrates in general was the early appearance of bone, cartilage, and enamel-like substance. These materials became modified in later fishes, enabling them to adapt to many aquatic environments and finally even to land. Other basic organs and tissues of the vertebrates—such as the central nervous system, heart, liver, digestive tract, kidney, and circulatory system— undoubtedly were present in the ancestors of the agnathans. In many ways, bone, both external and internal, was the key to vertebrate evolution.

 

The next class of fishes to appear was the Acanthodii, containing the earliest known jawed vertebrates, which arose in the Late Silurian, more than 416 million years ago. The acanthodians declined after the Devonian but lasted into the Early Permian, a little less than 280 million years ago. The first complete specimens appear in Lower Devonian freshwater deposits, but later in the Devonian and Permian some members appear to have been marine. Most were small fishes, not more than 75 cm (approximately 30 inches) in length.

 

We know nothing of the ancestors of the acanthodians. They must have arisen from some jawless vertebrate, probably in fresh water. They appear to have been active swimmers with almost no head armour but with large eyes, indicating that they depended heavily on vision. Perhaps they preyed on invertebrates. The rows of spines and spinelike fins between the pectoral and pelvic fins give some credence to the idea that paired fins arose from “fin folds” along the body sides.

 

The relationships of the acanthodians to other jawed vertebrates are obscure. They possess features found in both sharks and bony fishes. They are like early bony fishes in possessing ganoidlike scales and a partially ossified internal skeleton. Certain aspects of the jaw appear to be more like those of bony fishes than sharks, but the bony fin spines and certain aspects of the gill apparatus would seem to favour relationships with early sharks. Acanthodians do not seem particularly close to the Placodermi, although, like the placoderms, they apparently possessed less efficient tooth replacement and tooth structure than the sharks and the bony fishes, possibly one reason for their subsequent extinction.

Okay- seems unlikely, but things DO just keep happening. This afternoon, I ran out to feed our outside cats and inadvertently stepped back on Ivy's foot. It scared her enough that she bit me on the back of the ankle- through my Achilles tendon- all 4 incisors . . . Needless to say, Ken was some surprized when I limped into the house bleeding. I'd say at least it wasn't my right ankle, same as the bad knee, but this doesn't seem a lot better, with two legs hurting now . . . OMG. Wishing you all better health and luck!

 

Taken for the Jules' Photo Challenge Group:

The August 2015 Photo Challenge is a month long, black & white challenge that will consist of 1 photo per day. Each photo must pertain to something that happened in your life on that day- an event you attended, a person who had an impact on you, an object that played some role in your day.

  

The Southeast African cheetah (Acinonyx jubatus jubatus) is the nominate cheetah subspecies native to East and Southern Africa. The Southern African cheetah lives mainly in the lowland areas and deserts of the Kalahari, the savannahs of Okavango Delta, and the grasslands of the Transvaal region in South Africa. In Namibia, cheetahs are mostly found in farmlands.

 

The cheetah is a medium-sized cat. An adult male cheetah's total size can measure from 168 to 200 cm (66 to 79 in) and 162 to 213 cm (64 to 84 in) for females. Adult cheetahs are 70 to 90 cm (28 to 35 in) tall at the shoulder. Males are slightly taller than females and have slightly bigger heads with wider incisors and longer mandibles.

 

The cheetah has a bright yellow or sometimes a golden coat, and its fur is slightly thicker than that of other subspecies. The white underside is very distinct, especially on the neck and breast, and it has less spotting on its belly. The spots on the face are more pronounced, and as a whole its spots seem more dense than those of most other subspecies. The tear marks are notably thicker at the corners of the mouth, and almost all of them have distinct brown mustache markings. Like the Asiatic cheetah, it is known to have fur behind its tail and have both white and black tips at the end of its tail. However, the cheetah may also have only a black tip at the end of its tail.

Ring Tailed Lemur - Wingham Wildlife Park, Kent, England - Sunday March 29th 2009.

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Well, I am now in Colchester, having driven down an empty motorway, if only everyday was a Bank Holiday..hey...now I know what it would have been like to drive in the 50's..:))

You can't beat being the only car on an empty motorway..:))

 

Anyhoo...I now have my Canon EOS 400D back...so I am now deciding where to go to test it out...so far the it seems to be working better then before it broke, so they must have fixed quite a lot of stuff....hopefully it means the auto focus will be working quicker now as well..:))

Hopefully you will see the results in a few days..:))

 

OK...if you have a Bank Holiday where you are, I hope you have a great one, otherwise enjoy your Monday, whatever you may be upto...I hope to catch up with your wonderful streams on Tuesday..:))

 

Oh....and seeing tiss the day...May the Fouth be with you..lol

  

From Wikipedia, the free encyclopedia ~ The Ring-tailed Lemur (Lemur catta) is a large Strepsirhine primate and the most recognized lemur due to its long, black and white ringed tail. It belongs to Lemuridae, one of four lemur families. It is the only member of the Lemur genus. Like all lemurs it is endemic to the island of Madagascar. Known locally as Hira (Malagasy) or Maki (French and Malagasy), it inhabits gallery forests to spiny scrub in the southern regions of the island. It is omnivorous and the most terrestrial of lemurs. The animal is diurnal, being active exclusively in daylight hours.

The Ring-tailed Lemur is highly social, living in groups of up to 30 individuals. It is also matriarchal, a trait common among lemurs but uncommon among other primates. To keep warm and reaffirm social bonds groups will huddle together forming a lemur ball. The Ring-tailed Lemur will also sunbathe, sitting upright facing its underside, with its thinner white fur towards the sun. Like other lemurs, this species relies strongly on its sense of smell and marks its territory with scent glands. The males perform a unique scent marking behavior called spur marking and will participate in stink fights by impregnating their tail with their scent and wafting it at opponents.

As one of the most vocal primates, the Ring-tailed Lemur utilizes numerous vocalizations including group cohesion and alarm calls. Despite the lack of a large brain (relative to Simiiform primates) experiments have shown that the Ring-tailed Lemur can organize sequences, understand basic arithmetic operations and preferentially select tools based on functional qualities.

Despite being listed as Near Threatened by the IUCN Red List and suffering from habitat destruction, the Ring-tailed Lemur reproduces readily in captivity and is the most populous lemur in zoos worldwide, numbering more than 2000 individuals. It typically lives 16 to 19 years in the wild and 27 years in captivity.

 

Anatomy and physiology ~ An adult Ring-tailed Lemur may reach a body length between 39 and 46 cm (15 and 18 in) and a weight between 2.3 and 3.5 kg (5.1 and 7.7 lb). The species has a slender frame and narrow face, reminiscent of a vulpine muzzle. Like all lemurs, its hind limbs are longer than its forelimbs. Females have two pairs of mammary glands, but only one pair is functional.

Furless scent glands are present on both males and females. Both genders have apocrine and sebaceous glands in their genital regions, as well as antebrachial glands located on the inner surface of the forearm in proximity of the wrist. However, only the male has a horny spur that overlays this scent gland. The males also have brachial glands on the axillary surface of their shoulders.

The Ring-tailed Lemur's trademark, a long, bushy tail, is ringed in alternating black and white transverse stripes, numbering Thirteen to Fifthteen each for both colors, and always ending in a black tip. Its tail is longer than its body, measuring up to 64 cm (25.2 in) in length. The tail is not prehensile and is only used for balance, communication, and group cohesion.

The pelage, or fur, is dense. The ventral (chest) coat and throat are white or cream, and the dorsal (back) coat is gray to rosy-brown. The crown is dark gray, while the ears and cheeks are white. The muzzle is dark grayish and the nose is black, and the eyes are encompassed by black lozenge-shaped patches.

The black skin is visible on the nose, genitalia, and the palms and soles of the limbs. The Ring-tailed Lemur shares several adaptations with other lemurs. Its fingers are slender, padded, and semi-dexterous with flat, human-like nails. It grooms orally by licking and tooth-scraping with narrow, procumbent lower incisors and canines, called a toothcomb. Lastly, it has a toilet-claw (sometimes referred to as a grooming claw) on the second toe of each hind limb specialized for personal grooming, specifically to rake through fur that is unreachable by the mouth and toothcomb.

The species' eyes can be a bright yellow or orange. Unlike most diurnal primates, but like all strepsirhine primates, the Ring-tailed Lemur has a tapetum lucidum, or reflective layer behind the retina of the eye, that enhances night vision.

May 31st, 2011 -

Sadly this week we had to make a hard and traumatic decison for our Ms. Jackye.

 

She was suffering from a very strong form of jaws since several weeks and she couldn't eat anymore because of the lancinanting pain.

After trying to treat the infection with antibiotics without good results, we finally had to decide to submit her to the hated operation.

 

All moral and premolar teeth have been removed. Now she only owns her canines and the small incisors and she is completely dazed and disoriented... She doesn't understand what happened to her . Eating is still very difficult to her but we hope that in few weeks she will be able to learn how to eat what she loves more: tuna kibbles!

 

Jackye, you will always have the most beautiful smile to us. We love you even more than before our sweet girl!

 

June 10, 2011

We wish to thank all our great Flickr friends for all gentle thoughts, comments and suggestions, We carefully read all of them and take into consideration all what can be useful for trying to letting her feel less depressed and help her in improving her attempts to eat.

Thanks again friends, Jackye knows she has a great family here!

 

June 16th, 2011

One good news, one bad news:

Jackye starts to eat again her usual food (not much but it takes time to learn..) and her mouth looks good. The infection seems to be stopped and the vet said no need to remove the rest of her teeth.

 

The bad news is that in the first two weeks after the operation she couldn't eat so we tried to give to her some different food which would push her to eat. Since the beginning, all of our cats were used to eating only two types of brands of food (I do not mean to advertise name of the producers, it wouldn't be correct) and mainly solid food. Only one can of humid food devided for all of them in the morning.

Well, the result of changing the food is that Jackye had a strong allergic reaction and her body is now completely devastated and covered with terrible open sores and crusts.

Because of her thick fur, We could not notice it immediately but only after about ten days.

We immediately understood it was the food and not a reaction to the antibiotics.

So we stopped it and now she needs to wear a baby t-shirt so that she will not try to lick the wounds which in some points of her body became like holes ( the vet had to shave a good part of her body to let breathe the wounds)

 

Now we started again to treat her with antibiotic to try to solve this problem in the fastest way.

We really hope this hard period will soon end for our sweet girl. Incredible how she never complains to all what we are doing to her. We really think she is able to understand we are doing all this because we love her.

 

Thanks again to you all for the kind support and gentle thoughts to our sweetest girl.

  

View On Black

Incisioni semplici, essenziali di fine anni 80 fatte in cucina con un incisore a vibrazioni, dannatamente rumoroso.

Side view of the apical third of the root canal of a maxillary lateral incisor with necrotic pulp and chronic periapical lesion adhered to the tooth structure.

 

Courtesy of Ms. Thaís Silva

 

Image Details

Instrument used: Quanta SEM

Magnification: 130X

Horizontal Field Width: 2.30 mm

Voltage: 20 kV

Spot: 4.0

Working Distance: 15.4 mm

Detector: Mix SE+ BSE

 

Hippopotamuses love water, which is why the Greeks named them the "river horse." Hippos spend up to 16 hours a day submerged in rivers and lakes to keep their massive bodies cool under the hot African sun. Hippos are graceful in water, good swimmers, and can hold their breath underwater for up to five minutes. However, they are often large enough to simply walk or stand on the lake floor, or lie in the shallows. Their eyes and nostrils are located high on their heads, which allows them to see and breathe while mostly submerged. Hippos also bask on the shoreline and secrete an oily red substance, which gave rise to the myth that they sweat blood. The liquid is actually a skin moistener and sunblock that may also provide protection against germs. At sunset, hippopotamuses leave the water and travel overland to graze. They may travel 6 miles (10 kilometers) in a night, along single-file pathways, to consume some 80 pounds (35 kilograms) of grass. Considering their enormous size, a hippo's food intake is relatively low. If threatened on land hippos may run for the water—they can match a human's speed for short distances. Hippo calves weigh nearly 100 pounds (45 kilograms) at birth and can suckle on land or underwater by closing their ears and nostrils. Each female has only one calf every two years. Soon after birth, mother and young join schools that provide some protection against crocodiles, lions, and hyenas. Hippos once had a broader distribution but now live in eastern central and southern sub-Saharan Africa, where their populations are in decline. A partially submerged hippopotamus tries to keep cool in the hot African sun. The hippopotamus (Hippopotamus amphibius), or hippo, from the ancient Greek for "river horse" (ἱπποπόταμος), is a large, mostly herbivorous mammal in sub-Saharan Africa, and one of only two extant species in the family Hippopotamidae (the other is the Pygmy Hippopotamus.) After the elephant and rhinoceros, the hippopotamus is the third largest land mammal and the heaviest extant artiodactyl. Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, their closest living relatives are cetaceans (whales, porpoises, etc.) from which they diverged about 55 million years ago. The common ancestor of whales and hippos split from other even-toed ungulates around 60 million years ago. The earliest known hippopotamus fossils, belonging to the genus Kenyapotamus in Africa, date to around 16 million years ago.

The hippopotamus is semi-aquatic, inhabiting rivers, lakes and mangrove swamps, where territorial bulls preside over a stretch of river and groups of 5 to 30 females and young. During the day they remain cool by staying in the water or mud; reproduction and childbirth both occur in water. They emerge at dusk to graze on grass. While hippopotamuses rest near each other in the water, grazing is a solitary activity and hippos are not territorial on land. Hippos are recognizable by their barrel-shaped torso, enormous mouth and teeth, nearly hairless body, stubby legs and tremendous size. It is the third largest land mammal by weight (between 1½ and 3 tonnes), behind the white rhinoceros (1½ to 3½ tonnes) and the three species of elephant (3 to 9 tonnes). The hippopotamus is one of the largest quadrupeds and despite its stocky shape and short legs, it can easily outrun a human. Hippos have been clocked at 30 km/h (19 mph) over short distances. The hippopotamus is one of the most aggressive creatures in the world and is often regarded as one of the most dangerous animals in Africa. They are still threatened by habitat loss and poaching for their meat and ivory canine teeth. There is also a colony of non-zoo hippos in Colombia introduced by Pablo Escobar. The most recent theory of the origins of Hippopotamidae suggests that hippos and whales shared a common semi-aquatic ancestor that branched off from other artiodactyls around 60 million years ago.[13][15] This hypothesized ancestral group likely split into two branches around 54 million years ago.[12] One branch would evolve into cetaceans, possibly beginning about 52 million years ago with the proto-whale Pakicetus and other early whale ancestors collectively known as Archaeoceti, which eventually underwent aquatic adaptation into the completely aquatic cetaceans.[17] The other branch became the anthracotheres, a large family of four-legged beasts, the earliest of whom in the late Eocene would have resembled skinny hippopotamuses with comparatively small and narrow heads. All branches of the anthracotheres, except that which evolved into Hippopotamidae, became extinct during the Pliocene without leaving any descendants.[15]

A rough evolutionary lineage can be traced from Eocene and Oligocene species: Anthracotherium and Elomeryx to the Miocene Merycopotamus and Libycosaurus and the very latest anthracotheres in the Pliocene.[18] Merycopotamus, Libycosaurus and all hippopotamids can be considered to form a clade, with Libycosaurus being more closely related to hippos. Their common ancestor would have lived in the Miocene, about 20 million years ago. Hippopotamids are therefore deeply nested within the family Anthracotheriidae. The Hippopotamidae are believed to have evolved in Africa; the oldest known hippopotamid is the genus Kenyapotamus which lived in Africa from 16 to 8 million years ago. While hippopotamid species spread across Asia and Europe, no hippopotamuses have ever been discovered in the Americas, although various anthracothere genera emigrated into North America during the early Oligocene. From 7.5 to 1.8 million years ago an ancestor to the modern hippopotamus, Archaeopotamus, lived in Africa and the Middle East.[19]

While the fossil record of hippos is still poorly understood, the two modern genera, Hippopotamus and Choeropsis (sometimes Hexaprotodon), may have diverged as far back as 8 million years ago. Taxonomists disagree whether or not the modern Pygmy Hippopotamus is a member of Hexaprotodon —an apparently paraphyletic genus also embracing many extinct Asian hippopotamuses that is more closely related to Hippopotamus, or Choeropsis —an older and basal genus.[18][19]

[edit]Extinct species

Three species of Malagasy Hippopotamus became extinct during the Holocene on Madagascar, one of them within the past 1,000 years. The Malagasy Hippos were smaller than the modern hippopotamus, likely through the process of insular dwarfism.[20] There is fossil evidence that many Malagasy Hippos were hunted by humans, a likely factor in their eventual extinction.[20] Isolated members of Malagasy Hippopotamus may have survived in remote pockets; in 1976, villagers described a living animal called the Kilopilopitsofy, which may have been a Malagasy Hippopotamus.[21]

Two species of Hippopotamus, the European Hippopotamus (H. antiquus) and H. gorgops ranged throughout continental Europe and the British Isles. Both species became extinct before the last glaciation. Ancestors of European Hippos found their way to many islands of the Mediterranean during the Pleistocene.[22] Both species were larger than the modern hippopotamus, averaging about 1 meter (3.3 feet) longer. The Pleistocene also saw a number of dwarf species evolve on several Mediterranean islands including Crete (H. creutzburgi), Cyprus (H. minor), Malta (H. melitensis) and Sicily (H. pentlandi). Of these, the Cyprus Dwarf Hippopotamus, survived until the end of the Pleistocene or early Holocene. Evidence from an archaeological site Aetokremnos, continues to cause debate on whether or not the species was encountered, and was driven to extinction, by man. Hippopotamuses are among the largest living mammals; only elephants and some rhinoceroses and whales are heavier. They can live in the water or on land. Their specific gravity allows them to sink and walk or run along the bottom of a river. Hippos are considered megafauna, but unlike all other African megafauna, hippos have adapted for a semi-aquatic life in freshwater lakes and rivers.[9]:3 A hippo's lifespan is typically 40–50 years.[6]:277 Donna the Hippo, 60, was the oldest living hippo in captivity. She lived at the Mesker Park Zoo in Evansville, Indiana, USA[24][25] until her death on August 1, 2012. The oldest hippo ever recorded was called Tanga; she lived in Munich, Germany, and died in 1995 at the age of 61.[26]

Because of their enormous size, hippopotamuses are difficult to weigh in the wild. Most estimates of the weight come from culling operations that were carried out in the 1960s. The average weights for adult males ranged between 1,500–1,800 kg (3,300–4,000 lb). Females are smaller than their male counterparts, with average weights measuring between 1,300–1,500 kg (2,900–3,300 lb).[9]:12 Older males can get much larger, reaching at least 3,200 kg (7,100 lb) with a few exceptional specimens exceeding 3,600 kg (7,900 lb).[27][28] The heaviest known hippopotamus weighed approximately 4,500 kg (9,900 lb).[29] Male hippos appear to continue growing throughout their lives; females reach a maximum weight at around age 25.[30]

Hippos measure 3.3 to 5.2 meters (11 to 17 ft) long, including a tail of about 56 centimeters (22 in) in length and average about 1.5 meters (5 ft) tall at the shoulder.[31][32] The range of hippopotamus sizes overlaps with the range of the white rhinoceros; use of different metrics makes it unclear which is the largest land animal after elephants. Even though they are bulky animals, hippopotamuses can run faster than a human on land. Estimates of their running speed vary from 30 km/h (18 mph) to 40 km/h (25 mph), or even 50 km/h (30 mph). The hippo can maintain these higher speeds for only a few hundred meters. Despite being semi-aquatic and having webbed feet, an adult hippo is not a particularly good swimmer nor can it float. It is rarely found in deep water; when it is, the animal moves by porpoise-like leaps from the bottom. The eyes, ears, and nostrils of hippos are placed high on the roof of the skull. This allows them to be in the water with most of their body submerged in the waters and mud of tropical rivers to stay cool and prevent sunburn. Their skeletal structure is graviportal, adapted to carrying the animals' enormous weight. Hippopotamuses have small legs (relative to other megafauna) because the water in which they live reduces the weight burden. Unlike most other semi-aquatic animals, the hippopotamus has very little hair.[6]:260 The skin is 6 in (15 cm) thick,[33] providing it great protection against conspecifics and predators. The animals's upper parts are purplish-gray to blue-black while the under parts and areas around the eyes and ears can be brownish-pink.[6]:260 The testes of the males descend only partially and a scrotum is not present. In addition, the penis retracts into the body when not erect. The genitals of the female are unusual in that the vagina is ridged and two large diverticula protrude from the vulval vestibule. The function of these is unknown.[9]:28–29

The hippo's jaw is powered by a large masseter and a well developed digastric; the latter loops up behind the former to the hyoid.[6]:259 The jaw hinge is located far back enough to allow the animal to open its mouth at almost 180°.[9]:17 On the National Geographic Channel television program, "Dangerous Encounters with Brady Barr", Dr. Brady Barr measured the bite force of an adult female hippo at 8100 N (1821 lbf); Barr also attempted to measure the bite pressure of an adult male hippo, but had to abandon the attempt due to the male's aggressiveness.[34] Hippopotamus teeth sharpen themselves as they grind together. The lower canines and lower incisors are enlarged, especially in males, and grow continuously. The incisors can reach 40 cm (16 in) while the canines reach up to 50 cm (20 in).[33]

Their skin secretes a natural sunscreen substance which is red-colored. The secretion is sometimes referred to as "blood sweat," but is neither blood nor sweat. This secretion is initially colorless and turns red-orange within minutes, eventually becoming brown. Two distinct pigments have been identified in the secretions, one red (hipposudoric acid) and one orange (norhipposudoric acid). The two pigments are highly acidic compounds. Both pigments inhibit the growth of disease-causing bacteria; as well, the light absorption of both pigments peaks in the ultraviolet range, creating a sunscreen effect. All hippos, even those with different diets, secrete the pigments, so it does not appear that food is the source of the pigments. Instead, the animals may synthesize the pigments from precursors such as the amino acid tyrosine. Hippopotamus amphibius was widespread in North Africa and Europe during the Eemian[36] and late Pleistocene until about 30,000 years ago. The species was common in Egypt's Nile region during antiquity but has since been extirpated. Pliny the Elder writes that, in his time, the best location in Egypt for capturing this animal was in the Saite nome;[37] the animal could still be found along the Damietta branch after the Arab Conquest in 639. Hippos are still found in the rivers and lakes of the northern Democratic Republic of the Congo, Uganda, Tanzania and Kenya, north through to Ethiopia, Somalia and Sudan, west from Ghana to Gambia, and also in Southern Africa (Botswana, Republic of South Africa, Zimbabwe, Zambia, Mozambique). Genetic evidence suggests that common hippos in Africa experienced a marked population expansion during or after the Pleistocene Epoch, attributed to an increase in water bodies at the end of the era. These findings have important conservation implications as hippo populations across the continent are currently threatened by loss of access to fresh water.[10] Hippos are also subject to unregulated hunting and poaching. In May 2006 the hippopotamus was identified as a vulnerable species on the IUCN Red List drawn up by the World Conservation Union (IUCN), with an estimated population of between 125,000 and 150,000 hippos, a decline of between 7% and 20% since the IUCN's 1996 study. Zambia (40,000) and Tanzania (20,000–30,000) possess the largest populations.[1]

The hippo population declined most dramatically in the Democratic Republic of the Congo.[38] The population in Virunga National Park had dropped to 800 or 900 from around 29,000 in the mid 1970s.[39] The decline is attributed to the disruptions caused by the Second Congo War.[39] The poachers are believed to be former Hutu rebels, poorly paid Congolese soldiers, and local militia groups.[39] Reasons for poaching include the belief that hippos are harmful to society, and also for money.[40] The sale of hippo meat is illegal, but black-market sales are difficult for Virunga National Park officers to track. Invasive potential

In the late 1980s, Pablo Escobar kept four hippos in a private menagerie at his residence in Hacienda Napoles, 100 km east of Medellín, Colombia, after buying them in New Orleans. They were deemed too difficult to seize and move after Escobar's fall, and hence left on the untended estate. By 2007, the animals had multiplied to 16 and had taken to roaming the area for food in the nearby Magdalena River.[41] In 2009, two adults and one calf escaped the herd, and after attacking humans and killing cattle, one of the adults (called "Pepe") was killed by hunters under authorization of the local authorities.[42][43] It is unknown what kind of effects the presence of hippos might have on the ecosystem in Colombia. According to experts interviewed by W Radio Colombia, the animals could survive in the Colombian jungles. It is believed that the lack of control from the Colombian government, which is not used to dealing with this species, could result in human fatalities. Hippos spend most of their days wallowing in the water or the mud, with the other members of their pod. The water serves to keep their body temperature down, and to keep their skin from drying out. With the exception of eating, most of hippopotamuses' lives —from childbirth, fighting with other hippos, to reproduction— occur in the water. Hippos leave the water at dusk and travel inland, sometimes up to 8 kilometers (5 mi), to graze on short grass, their main source of food. They spend four to five hours grazing and can consume 68 kilograms (150 lb) of grass each night.[44] Like almost any herbivore, they will consume many other plants if presented with them, but their diet in nature consists almost entirely of grass, with only minimal consumption of aquatic plants.[45] Hippos have (rarely) been filmed eating carrion, usually close to the water. There are other reports of meat-eating, and even cannibalism and predation.[46] The stomach anatomy of a hippo is not suited to carnivory, and meat-eating is likely caused by aberrant behavior or nutritional stress.[9]:84

The diet of hippos consists mostly of terrestrial grasses, even though they spend most of their time in the water. Most of their defecation occurs in the water, creating allochthonous deposits of organic matter along the river beds. These deposits have an unclear ecological function.[45] Because of their size and their habit of taking the same paths to feed, hippos can have a significant impact on the land they walk across, both by keeping the land clear of vegetation and depressing the ground. Over prolonged periods hippos can divert the paths of swamps and channels.[47]

Adult hippos move at speeds up to 8 km/h (5 mph) in water. Adult hippos typically resurface to breathe every three to five minutes. The young have to breathe every two to three minutes.[9]:4 The process of surfacing and breathing is automatic, and even a hippo sleeping underwater will rise and breathe without waking. A hippo closes its nostrils when it submerges into the water. As with fish and turtles on a coral reef, hippo occasionally visit cleaning stations and signal by wide-open mouth their readiness for being cleaned of parasites by certain species of fish. This situation is an example of mutualism in which the hippo benefits from the cleansing while the fish receive food.[ Studying the interaction of male and female hippopotamuses has long been complicated by the fact that hippos are not sexually dimorphic and thus females and young males are almost indistinguishable in the field.[49] Although hippos like to lie close to each other, they do not seem to form social bonds except between mothers and daughters, and are not social animals. The reason they huddle close together is unknown.[9]:49

Hippopotamuses are territorial only in water, where a bull presides over a small stretch of river, on average 250 meters in length, and containing ten females. The largest pods can contain over 100 hippos.[9]:50 Other bachelors are allowed in a bull's stretch, as long as they behave submissively toward the bull. The territories of hippos exist to establish mating rights. Within the pods, the hippos tend to segregate by gender. Bachelors will lounge near other bachelors, females with other females, and the bull on his own. When hippos emerge from the water to graze, they do so individually.[9]:4

Hippopotamuses appear to communicate verbally, through grunts and bellows, and it is thought that they may practice echolocation, but the purpose of these vocalizations is currently unknown. Hippos have the unique ability to hold their head partially above the water and send out a cry that travels through both water and air; hippos above and under water will respond.[ Female hippos reach sexual maturity at five to six years of age and have a gestation period of 8 months. A study of endocrine systems revealed that female hippopotamuses may begin puberty as early as 3 or 4 years of age.[51] Males reach maturity at around 7.5 years. A study of hippopotamus reproductive behavior in Uganda showed that peak conceptions occurred during the end of the wet season in the summer, and peak births occurred toward the beginning of the wet season in late winter. This is because of the female's estrous cycle; as with most large mammals, male hippopotamus spermatozoa is active year round. Studies of hippos in Zambia and South Africa also showed evidence of births occurring at the start of the wet season.[9]:60–61 After becoming pregnant, a female hippopotamus will typically not begin ovulation again for 17 months.[51]

Mating occurs in the water with the female submerged for most of the encounter,[9]:63 her head emerging periodically to draw breath. Baby hippos are born underwater at a weight between 25 and 45 kg (60–110 lb) and an average length of around 127 cm (50 in) and must swim to the surface to take their first breath. A mother typically gives birth to only one hippo, although twins also occur. The young often rest on their mothers' backs when in water that is too deep for them, and they swim underwater to suckle. They also will suckle on land when the mother leaves the water. Weaning starts between six and eight months after birth and most calves are fully weaned after a year.[9]:64 Like many other large mammals, hippos are described as K-strategists, in this case typically producing just one large, well-developed infant every couple of years (rather than large numbers of small, poorly developed young several times per year as is common among small mammals such as rodents. Hippopotamuses are by nature very aggressive animals, especially when young calves are present. Frequent targets of their aggression include crocodiles, which often inhabit the same river habitat as hippos. Nile crocodiles, lions and spotted hyenas are known to prey on young hippos.[53] Hippos are very aggressive towards humans, whom they commonly attack whether in boats or on land with no apparent provocation.[54] They are widely considered to be one of the most dangerous large animals in Africa.[55][56]

To mark territory, hippos spin their tails while defecating to distribute their excrement over a greater area.[57] Likely for the same reason, hippos are retromingent – that is, they urinate backwards.[58] When in combat, male hippos use their incisors to block each others attacks, and their lower canines to inflict damage.[6]:260 Hippos rarely kill each other, even in territorial challenges. Usually a territorial bull and a challenging bachelor will stop fighting when it is clear that one hippo is stronger. When hippos become overpopulated, or when a habitat starts to shrink, bulls will sometimes attempt to kill infants, but this behavior is not common under normal conditions.[52] Some incidents of hippo cannibalism have been documented, but it is believed to be the behavior of distressed or sick hippos, and not healthy behavior. The earliest evidence of human interaction with hippos comes from butchery cut marks upon hippo bones at Bouri Formation dated around 160,000 years ago.[59] Later rock paintings and engravings showing hippos being hunted have been found in the mountains of the central Sahara dated 4,000–5,000 years ago near Djanet in the Tassili n'Ajjer Mountains.[9]:1 The ancient Egyptians recognized the hippo as a ferocious denizen of the Nile.

The hippopotamus was also known to the Greeks and Romans. The Greek historian Herodotus described the hippopotamus in The Histories (written circa 440 BC) and the Roman Historian Pliny the Elder wrote about the hippopotamus in his encyclopedia Naturalis Historia (written circa 77 AD).[37][60] Hippopotamus was one of the many exotic animals brought to fight gladiators in Rome by the emperor Philip I the Arab to commemorate Rome's 1000 years anniversary in 248 AD. Silver coins with hippo's image were minted that year.[citation needed]

Zulu warriors preferred to be as brave as a hippopotamus, since even lions were not considered as brave. "In 1888, Captain Baden-Powell was part of a column searching for the Zulu chief Dinizulu, who was leading the Usutu people in revolt against the British colonists. The column was joined by John Dunn, a white Zulu chief, who led an impi (army) of 2000 Zulu warriors to join the British." [61]

The words of the Zulu anthem sounded like this:

"Een-gonyama Gonyama! "Invooboo! Yah-bo! Yah-bo! Invooboo!"

"John Dunn was at the head of his impi. [Baden Powell] asked him to translate the Zulu anthem his men had been singing. Dunn laughed and replied: "He is a lion. Yes, he is better than a lion—he is a hippopotamus. Hippopotamuses have long been popular zoo animals. The first zoo hippo in modern history was Obaysch who arrived at the London Zoo on May 25, 1850, where he attracted up to 10,000 visitors a day and inspired a popular song, the Hippopotamus Polka.[63] Hippos have remained popular zoo animals since Obaysch, and generally breed well in captivity. Their birth rates are lower than in the wild, but this is attributed to zoos' not wanting to breed as many hippos as possible, since hippos are large and relatively expensive animals to maintain.[9]:129[63]

Like many zoo animals, hippos were traditionally displayed in concrete exhibits. In the case of hippos, they usually had a pool of water and patch of grass. In the 1980s, zoo designers increasingly designed exhibits that reflected the animals' native habitats. The best known of these, the Toledo Zoo Hippoquarium, features a 360,000 gallon pool for hippos.[64] In 1987, researchers were able to tape, for the first time, an underwater birth (as in the wild) at the Toledo Zoo. The exhibit was so popular that the hippos became the logo of the Toledo Zoo. A red hippo represented the Ancient Egyptian god Set; the thigh is the 'phallic leg of set' symbolic of virility. Set's consort Tawaret was also seen as part hippo.[66] The hippopotamus-headed Tawaret was a goddess of protection in pregnancy and childbirth, because ancient Egyptians recognized the protective nature of a female hippopotamus toward her young.[67] The Ijo people wore masks of aquatic animals like the hippo when practicing their water spirit cults.[68] The Behemoth from the Book of Job, 40:15–24 is also thought to be based on a hippo.[69]

Hippos have been the subjects of various African folktales. According to a Bushmen story; when the Creator assigned each animal their place in nature, the hippos wanted to live in the water, but were refused out of fear that they might eat all the fish. After begging and pleading, the hippos were finally allowed to live in the water on the conditions that they would eat grass instead of fish and would fling their dung so that it can be inspected for fish bones.[70] In a Ndebele tale, the hippo originally had long, beautiful hair but was set on fire by a jealous hare and had to jump into a nearby pool. The hippo lost most of his hair and was too embarrassed to leave the water.[70]

Ever since Obaysch inspired the Hippopotamus Polka, hippos have been popular animals in Western culture for their rotund appearance that many consider comical.[63] Stories of hippos like Huberta who became a celebrity in South Africa in the 1930s for trekking across the country;[71] or the tale of Owen and Mzee, a hippo and tortoise who developed an intimate bond; have amused people who have bought hippo books, merchandise, and many a stuffed hippo toy.[72][73] Hippos were mentioned in the novelty Christmas song "I Want a Hippopotamus for Christmas" that became a hit for child star Gayla Peevey in 1953.[74] They also feature in the songs "The Hippopotamus" and "Hippo Encore" by Flanders and Swann, with the famous refrain Mud, Mud, Glorious Mud. They even inspired a popular board game, Hungry Hungry Hippos. Hippos have also been popular cartoon characters, where their rotund frame is used for humorous effect. The Disney film Fantasia featured a ballerina hippopotamus dancing to the opera, La Gioconda.[38] Other cartoon hippos have included Hanna-Barbera's Peter Potamus, the book and TV series George and Martha, Flavio and Marita on the Animaniacs, Pat of the French duo Pat et Stanley, The Backyardigan's Tasha, and Gloria and Moto-Moto from the Madagascar franchise. A Sesame Street cartoon from the early 1970s features a hippo who lives in the country and likes it quiet, while being disturbed when the mouse who likes it loud moves in with her.[citation needed]

The hippopotamus characters "Happy Hippos" were created in 1988 by the French designer Andre Roche [77] based in Munich, to be hidden in the "Kinder Surprise egg" of the Italian chocolate company Ferrero SpA. These characters were not placid like real hippos[contradiction] but rather cute and lively, and had such a success that they reappeared several times in different products of this company in the following years, increasing their popularity worldwide each time.[citation needed] The Nintendo Company published in the years 2001 and 2007 Game Boy adventures of them. In the game of chess, the hippopotamus lends its name to the Hippopotamus Defense, an opening system, which is generally considered weak.The River Horse is a popular outdoor sculpture at George Washington University, Washington, D.C. Botswana, Moremi National Park, Moremi Game reserve, private Reserve, Farm, chobe National park, Chobe Game Reserve, Zambia, Zambezi River, Livingstone, Zimbabwe, Kenya, Tanzania, Wildlife Conservation Project, Maramba River Lodge, South Africa, Krugger National Park. art beach blue bw california canada canon china city concert de england europe family festival film flower flowers food france friends green instagramapp iphoneography italy japan live london music nature new newyork night nikon nyc paris park party people photography portrait red sky snow square squareformat street summer sunset travel trip uk usa vacation water wedding white winter

Antonio Tempesta

Antonio Tempesta detto il Tempestino (Firenze, 1555 – Roma, 5 agosto 1630) è stato un pittore e incisore italiano del primo periodo barocco.

Biografia

Si formò nella cultura del tardo manierismo, con un gusto naturalistico ma anche calligrafico, acquisito dalla frequentazione di Giovanni Stradano, con il quale collaborò alla decorazione di Palazzo Vecchio.

 

Trasferitosi a Roma nel 1573, lavorò per Papa Gregorio XIII affrescando alcune mappe della Sala delle carte geografiche in Vaticano, tra le quali la famosa Mappa di Roma (1593). Nella capitale pontificia lavorò per molte nobili famiglie e per importanti cardinali come Alessandro Farnese e Scipione Borghese. Sono presenti sue opere a San Giovanni dei Fiorentini, alla villa di Caprarola, a Tivoli.

 

Tornò a Firenze per un breve soggiorno, dove collaborò con Alessandro Allori, Ludovico Buti, Giovan Maria Butteri e Ludovico Cigoli alla decorazione dei soffitti della Galleria degli Uffizi nel lato est, eseguita con disegni a grottesche. Ritrasferitosi a Roma si dedicò sempre di più all'incisione, con la quale raggiunse un'ampia fama e diffusione in tutta Europa. Celeberrime le 150 illustrazioni dell'Antico Testamento note come la Bibbia del Tempesta.

 

Fu anche un bravo disegnatore, dotato di una vena particolarmente scenografica, e altri artisti stamparono e diffusero la sua opera nel disegno.

 

L'opera pittorica

"Principiando adunque dalle Pitture diremo che quello Artefice manifestò il suo valore nella Città di Roma, fioritissima sede di tutte le buone Arti, dove erasi portato mentre regnava il Sommo Pontefice Gregorio XIII. Quivi operò varie cose nella Galleria e nelle Logge del Palazzo Papale in Vaticano, tra le quali incontrarono il genio universale alcune vivacissime e spiritose figure a fresco nella storia che rappresenta la traslazione del Corpo di S. Gregorio Nazianzeno, ed i lavori che fece nella Sala dei Tedeschi cioè due belle figure esprimenti la Fama e l'Onore, ed alcune storiette poste sotto le finestre figurate di color giallo".

 

"La buona maniera che fu ravvisata in questi lavori dagli intendenti fece sì che il Cardinale Alessandro Farnese gli ordinasse di ornare coi suoi pennelli i pilastretti della Lumaca nel famoso Palazzo Farnese di Caprarola e che il Cardinal Gambero gli facesse dipingere altre cose nel suo Palazzo di Bagnaia; e perché nell'esecuzione di tali lavori si portò Antonio da valente Maestro, sempre più crebbegli il credito onde gli furono commesse in Roma opere assai più vaste e importanti. Fece pertanto a fresco la Strage degl'Innocenti e la Vergine con i sette dolori, nelle due facciate dell'Altar Maggiore di S. Stefano Rotondo e, nel Palazzo del Marchese Santa Croce sotto il Campidoglio, rappresentò due Battaglie, una terrestre e l'altra marittima, con rara e copiosa invenzione. Dopo aver terminate queste pitture, lavorò molto nel Palazzo Giustiniani, incontro alle antiche Terme di Nerone e nel Palazzo presso a' Cavalli del Monte Quirino, per il Cardinale Scipione Borghese a cui in quel tempo apparteneva: figurò nella Loggia due nobilissime Cavalcate che girano intorno alla medesima a guisa di fregio. In una di esse vedesi il Papa allorché solennemente cavalca con seguito numeroso di uomini a piedi e a cavallo; nell'altra egualmente ricca di figure e di ornamenti è il Gran Turco pure a cavallo accompagnato dalla sua Corte".

 

[...] "Né queste furono le sole produzioni del suo sapere che tanto di nome e di onore fecero acquietargli nella Capitale del Mondo; perocché dipinse ancora in S. Giovanni dei Fiorentini la Cappella di S. Antonio Abate dalla cornice in giù e, sopra la volta, le storie di S. Lorenzo a fresco; in S Pancrazio, per il Cardinale Lodovico de Torres, molti Santi e Sante a fresco ed in S. Giovanni in Fonte, nella Cappella di S. Giovanni Evangelista, alcune eleganti Storiette colorite pure a fresco con eccellente maniera. Non si debbono altresì passare sotto silenzio le vaghissime grottesche e bizzarrie che fece in una Casa incontro ai Signori Gaetani al Corso, architettata da Giovanni Boccalini da Carpi, per essere state sempre universalmente applaudite. Nella nostra Firenze, oltre una sua tavola che vedesi da uno dei lati entro il coro di Santa Felicita rappresentante la gloriosa Resurrezione di Gesù Cristo, fece al celebre Pietro Strozzi alcune sacre Istorie dipinte sopra il Lapislazzuli e altre simili di sua mano espresse sopra vari alabastri, e si trovano nella Raccolta dei Signori Marchesi Niccolini ed in quella del più volte nominato Signore Ignazio Hugford diverse battaglie colorite sul marmo con gusto particolare, adattandosi industriosamente alle macchie dei medesimi marmi che lasciava in gran parte scoperti".

 

L'opera incisoria

"Venendo ora a parlare delle incisioni per lo più ad acqua forte, o eseguite di sua mano o fatte da altri col suo disegno, sarebbe cosa lunga e forse tediosa il descriverle ad una ad una, essendo quasi infinite. Accenneremo pertanto le principali E principiando dalle Sacre Storie son degne di essere ammirate le 220 piccole carte senza titolo che contengono molti fatti dell'antico Testamento dei quali pure rappresentò dodici soggetti in grande. Figurò altresì in 52 piccole carte ovate la vita della Santissima Vergine, di Gesù Cristo e di più Santi servendosi d'un sol contorno senza ombre; in otto carte l'Invenzione della Croce; in sei altre più Santi entro diversi Paesi per eccellenza toccati; in 159 carte i diversi strumenti dei Martiri, le quali stampò in Roma nel 1591; in 14 carte la vita di S. Antonio; in 20, diversi emblemi; per nulla dire della bellissima carta in foglio grande in cui vedesi una Città assediata con S. Jacopo a cavallo che ne da' le chiavi; e del Ritratto del Pontefice Clemente VIII intorno al quale pose varie storiette riguardanti la di lui vita. Disegnò poi quattro storie della Vergine che furono intagliate dal Callot; una Vergine circondata dagli Angioli e da più Santi intagliata da Filippo Tommasini; la Cena di nostro Signore con i 12 Articoli del Credo i quali furono pubblicati dal bulino del Villamena; la Conversion di S. Paolo intaglio di Filippo Tommasini e finalmente la vita ed i miracoli di S. Bernardo di Chiaravalle in foglio, intagliati ottimamente da Cherubino Alberti."

 

"Mostrano altresì quanto valesse nell'invenzione le Metamorfosi d'Ovidio che in 150 carte, in largo, da sé stesso intagliò; le dodici fatiche d'Ercole; le sette Meraviglie del Mondo; le dodici storie d'Alessandro Magno; le 11 Storie del Tasso e le quaranta carte che rappresentano l'intera storia dei sette figliuoli di Lara. Che diremo poi della figura sulle Nuvole con le armi dei Pinelli intagliata da Matteo Greuter che adoprò il suo bulino anche nel pubblicare altre opere dello stesso Autore; dei tre carri sulle nuvole, con figure sopra, col Ritratto di Alberto Arciduca d'Austria che pubblicò in carta grande Valeriano Regnartio; delle diverse invenzioni che vedonsi intagliate da Beniamino Vananglo; della Battaglia nella cui parte superiore sono due putti che reggono le armi Pontificie, intaglio del Villamena; e della carta grande per largo nella quale osservasi un Palazzo ed una Pallade ed in lontananza una battaglia con la Città di Caminiez incisa dallo slesso Tempesta?"

"Fu stimata assai una carta che egli intagliò figurandovi una Città assalita dal nemico con S. Michele Arcangiolo in aria ed incontrarono talmente il genio del pubblico 18 carte che siguravano le principali azioni di Alessandro il Grande che egli s' indusse a pubblicarle ancora in maggior grandezza."

"Resterà però molto più soddissatto chi osserverà la carta grande con la superba Battaglia dei Centauri che intagliò in legno Girolamo Parasoli; l'altra con la Battaglia di Druso coi Germani, intaglio di Matteo Greuter; e quella in cui vedesi in alto il Triregno Pontificio con le Chiavi, intaglio di Francesco Villamena. Sono tenute in grandissima stima la Battaglia di due fogli in largo dove sono incise dal Tempesta le seguenti parole Hebraeorum Victoria; le otto differenti Battaglie per largo esposte alla pubblica luce da Merian; e le altre che vengono dai bulini d'Orazio Brun e di altri. Non ci possiamo dispensare dal far parole della Battaglia delle Amazzoni che intagliò nel 1600; delle otto Battaglie per largo che seguirono tra Carlo V e Francesco I intagliate da Cornelio Boel e delle altre otto seguite fra Scipione ed Annibale perocché sono di particolare eccellenza; come pure ci convien fare menzione delle carte rappresentanti i 13 paraggi di fiumi diversi, quattro di Alessandro Magno, due di Annibale sopra un Elefante, ed uno d'Alessandro Farnese della Schelda."

 

"Infiniti per così dire sono gl'intagli dei diversi Paesi e delle cacce di ogni ispecie di animali che si ammirano di sua mano intagliate o almeno disegnate, ma noi ne rammenteremo soltanto alcune cioè le carte 96 in lungo con vari uccelli dedicate a Massimiliano Bruno; le 39 con cacce dedicate a Gio. Antonio Orsino Duca di S. Gemini; le 71 che compongono un libro d'uccelli del Tempesta e del Villamena di cui è fatta la dedica al Cavaliere del Pozzo; ed infine le carte contenenti una nuova raccolta dei più curiosi Animali. Si vedono di sua mano alcune superbissime Cavalcate che non si possono mai commendare abbastanza tra le quali quella che suol fare il Pontefice nell'andare a prendere il possesso di S. Gio. Laterano e quella del Gran Signore dei Turchi. Recano poi meraviglia le carte dei Cavalli in ogni attitudine disegnati, le quali dedicò a D. Virginio Orsino Duca di Bracciano. Si scorge da queste quanto fosse eccellente nel disegnare i cavalli, impresa ripiena d'infinite difficoltà, ed in vero i Maestri dell'Arte confessano che, avanti a Lui e allo Stradano, rare volte s' incontrano questi animali ad intera perfezione condotti."

 

Da Wikipedia, l'enciclopedia libera.

Raccolta Foto De Alvariis

Cleavers up, bring 'em here

Femurs all swing on the ceiling like a chandelier

She sittin' there in a white dress, looking like she should get it

Licking the lips of the reddest, should invest in a head clinic

She got a pocket full of incisors and pliers

In a briefcase in case she get inspired, she ain't

She tryin' to suck face off the bone

You should know she is prone to swallow the marrow

 

youtu.be/3ZAPtFRpuu8

Isola Tiberina

 

L'Isola Tiberina (nota anche come Insula Tiberina, Insula Tiberis, Insula Aesculapi, Isola dei Due Ponti, Licaonia, Isola di San Bartolomeo, o semplicemente Insula) è un'isola fluviale nonché l'unica isola urbana del Tevere, nel centro di Roma. Nella Forma Urbis di età severiana viene riportato con la definizione di "inter duos pontes": è infatti collegata alle due rive del Tevere dal Ponte Cestio e dal Ponte Fabricio.

 

Storia

 

La leggenda vuole che l'isola si sia formata nel 510 a.C. dai covoni del grano mietuto a Campo Marzio, di proprietà del re Tarquinio il Superbo, gettati nel Tevere al momento della rivolta che ne causò la cacciata. Alcuni studi moderni, però, proverebbero che l'isola ha origini molto anteriori all'evento. Poco coinvolta nelle vicissitudini della città, per questa ragione ospitò il tempio di Esculapio, dio della medicina, il cui culto fu introdotto nel 292 a.C. in seguito ad una pestilenza.

 

Nella prima metà del I secolo a.C. venne monumentalizzata in opera quadrata, parallelamente alla costruzione dei ponti Fabricio e Cestio, e del Vicus Censorius che li collegava al suo interno, dando all'isola la forma di una nave (di cui oggi è ancora visibile la prua), con blocchi di travertino che rivestono l'interno in peperino, e alcune decorazioni raffiguranti Esculapio con il suo serpente e una testa di toro, forse utile per gli ormeggi.

 

Al centro vi era un obelisco, a raffigurare un albero maestro simbolico, ricordo della nave romana che nel 292 a.C. da Epidauro portò a Roma il simbolo del dio Esculapio. Due anni prima, infatti, alcuni funzionari romani si erano recati nella città greca per visitarne il tempio e consultare la divinità a seguito di una grave pestilenza scoppiata a Roma. Il mito vuole che un serpente - simbolo del dio - si allontanò dal tempio e salì sulla nave romana. Quando la nave tornò a Roma, il rettile scese sull'isola stabilendovisi. Si racconta che la peste svanì miracolosamente dopo la costruzione del tempio dedicato al dio.

 

Monumenti

 

Templi

 

Il Tempio di Esculapio venne inaugurato nel 289 a.C. e sorgeva nella parte meridionale dell'isola, nel luogo oggi occupato dalla chiesa di San Bartolomeo: al suo interno un pozzo prenderebbe la posizione di una fonte collegata al santuario. Ai lati del tempio si trovava un portico per l'accoglienza dei pellegrini e soprattutto dei malati. Nella parte settentrionale si trovavano alcuni piccoli santuari legati a culti particolari, ora situati fra le fondamenta dell'Ospedale Fatebenefratelli. Questi erano: due templi dedicati nel 194 a.C. a Fauno e Veiove; un sacello per Iuppiter Iuralius (ossia "garante dei giuramenti"), oggi sostituito dalla chiesa di San Giovanni Calibita, ma in cui un pavimento musivo mostra una dedica al dio; un altare dedicato al dio Semo Sancus, di origine sabina. Altri culti attestati sull'isola erano rivolti a Tiberino e Gaia, e a Bellona (detta Insulensis).

 

Al posto dell'obelisco, dopo la sua scomparsa, venne eretta una colonna (poi trasferita nel portico della chiesa di San Bartolomeo) dove il 24 agosto di ogni anno si affiggeva l'elenco di chi non aveva seguito il precetto pasquale; la colonna si frantumò nel 1867 a causa dell'urto di un carro. Si racconta che nel 1834 Bartolomeo Pinelli, presente nella lista, si lamentò ufficialmente in sacrestia per essere stato inserito come miniatore, anziché incisore. Oggi sul luogo centrale si trova una piccola edicola reggicroce fatta costruire da papa Pio IX nel 1869 da parte di Ignazio Jacometti, che nelle quattro nicchie raffigurò i santi collegati all'isola: san Bartolomeo, san Paolino da Nola, san Francesco d'Assisi, e san Giovanni di Dio. Nella stessa data del 24 agosto ricorreva la festa dei cocomeri, in cui numerosi venditori esponevano la propria merce sull'isola; nel frattempo alcuni praticavano una gara di nuoto, dal ponte Fabricio a ponte Rotto per afferrare i cocomeri: i giochi sono stati proibiti nel 1870 a seguito degli incidenti dovuti alla corrente del fiume.

 

Basilica di San Bartolomeo

 

Sopra le rovine del tempio di Esculapio l'imperatore Ottone III volle costruire nel X secolo una chiesa dedicata ai santi Adalberto (suo amico, vescovo di Praga e martirizzato nel 998), Paolino e Bartolomeo, e che dopo il restauro di papa Alessandro III nel 1180 mantenne la dedica solamente per l'ultimo santo (allo stesso evento risale un frammento di mosaico oggi presente sulla facciata); in precedenza, nel 1113, era stato aggiunto un campanile da parte di papa Pasquale II. All'interno si trova un antico pozzo con un bassorilievo raffigurante i tre santi (o forse il Salvatore, sant'Adalberto, san Bartolomeo e Ottone III), realizzato con il rocchio di un'antica colonna da Nicola d'Angelo o da Pietro Vassalletto nel XIII secolo: i romani credevano che l'acqua fosse miracolosa, essendovisi trovate le ossa dei martiri romani Esuperanzio e Marcello, e un'iscrizione infatti riporta "Os putei Sci sancti circumdant orbe rotanti"; nel secolo scorso il pozzo è stato chiuso a causa della malsanità dell'acqua.

 

Nella chiesa, nella prima cappella a destra, è conservata l'immagine della Madonna della Lampada, legata all'inondazione del 1557 e alla tradizione del prodigio. L'immagine è una Madonna con Bambino affrescata nella seconda metà del XIII secolo, e posta sopra una mole, per cui era conosciuta anche come Madonna delle Mole. La tradizione vuole che in seguito ad una piena l'immagine fu sovrastata dalle acque, ma una lampada posta lì di fronte si mantenne accesa, e così rimase fino al termine dell'evento. Nella Cappella del Sacramento si trova invece una palla di cannone, di quattordici centimetri di diametro, sparata durante l'assedio di Roma del 1849: le persone che all'interno rimasero incredibilmente illese lasciarono l'oggetto sul luogo a ricordo dell'avvenimento.

 

Nel XVII secolo nacque la tradizione di una cerimonia in suffragio delle vittime del Tevere: ogni 2 novembre, giorno della commemorazione dei defunti, al tramonto dalla chiesa di San Bartolomeo una processione della Confraternita dei Sacconi Rossi di Santa Maria dell'Orto - noti semplicemente come Sacconi Rossi - si recava con alcune torce accese fino alla riva, dove benedicevano le acque e lanciavano una corona di fiori. Dopo anni d'interruzione, la cerimonia è stata ripresa dal 1984 dalla Confraternita dei Sacconi Scuri. Un'altra tradizione vuole che un frate lombardo, un certo Fra Giambattista Orsenigo, fosse un validissimo cavadenti, e che fra il 1867 e il 1903 ebbe come pazienti numerosissime personalità, fra cui il papa Leone XIII.

 

Nell'anno 1999 Giovanni Paolo II decise, in preparazione del Giubileo dell'anno 2000, di istituire una commissione "Nuovi Martiri", che avrebbe dovuto indagare sui martiri cristiani del Ventesimo secolo. La commissione ha lavorato due anni nei locali della Basilica di San Bartolomeo, raccogliendo circa 12.000 dossier di martiri e testimoni della fede giunti da diocesi di tutto il mondo.

 

Passato il Giubileo, Giovanni Paolo II volle che questa memoria dei testimoni della fede del Novecento potesse divenire qualcosa di visibile nella Basilica di San Bartolomeo. Nell'ottobre del 2002, con una solenne celebrazione ecumenica alla presenza dei cardinali Camillo Ruini, Walter Kasper e Francis Eugene George, e del patriarca romeno ortodosso Teoctist, è stata posta sull'altare maggiore una grande icona dedicata ai martiri del Novecento. L'icona rappresenta, con una simbologia presa dall'Apocalisse, le vicende dei martirii di cui si è venuti a conoscenza attraverso i lavori della commissione. Altre memorie di martiri sono collocate nelle cappelline laterali, ognuna dedicata ad una situazione storica particolare.

 

Ospedale Fatebenefratelli

L'ospedale Fatebenefratelli, posto di fronte alla basilica di San Bartolomeo, venne fondato dai seguaci di san Giovanni di Dio nel 1583, e rimodernato in seguito da Cesare Bazzani fra il 1930 ed il 1934. Sulla destra si trova la chiesa di San Giovanni Calibita, edificata sui resti del tempio di Iuppiter Iurarius, e dedicata intorno all'870: la facciata è opera nel 1640 di Luigi Barattoni, completata poi da Romano Carapecchia nel 1711.

 

Ospedale Israelitico

Oltre al già citato Fatebenefratelli, sull'Isola Tiberina è presente anche una delle tre sedi romane dell'Ospedale Israelitico. La sede è operante e si trova a fianco della basilica di San Bartolomeo.

 

L'Isola del Cinema 2009

L'Isola del Cinema è la manifestazione che porta, dal 1995, al centro della Capitale il grande cinema italiano e internazionale, eventi culturali e manifestazioni solidali ospitati nello scenario affascinante dell'Isola Tiberina. Un Salotto Internazionale di Cinema e Cultura sul fiume Tevere: nell'Arena, che ospita un maxischermo, è possibile seguire anteprime e pellicole inedite prestigiose, incontrare registi e attori italiani e internazionali e vedere alcuni tra i più bei film di qualità dell'ultima stagione, mentre nel Cinelab si svolgono rassegne di film d'autore, cortometraggi, rassegne dedicate alla cinematografia internazionale, il Nuovo Cinema Italiano, i migliori film della precedente stagione.

 

Da Wikipedia, l'enciclopedia libera.

Raccolta Foto De Alvariis

 

 

 

 

...le mie statue equestri esprimono il tormento causato dagli avvenimenti di questo secolo. L’inquietudine del mio cavallo aumenta a ogni nuova opera, il cavaliere è sempre più stremato, ha perduto il dominio sulla bestia e le catastrofi alle quali soccombe somigliano a quelle che distrussero Sodoma e Pompei. Io aspiro a rendere visibile l’ultimo stadio della dissoluzione di un mito, del mito dell’individualismo eroico e vittorioso, dell’uomo di virtù degli umanisti. La mia opera degli ultimi anni non vuole essere eroica, ma tragica.

 

Marino Marini, 1972

 

 

 

 

 

These marmosets are gum-feeding specialists. They don't wait for gum-producing trees to exude gum but use their specially adapted chisel-like incisors to make small holes in the bark.This stimulates the flow of gum and enables them to have a year round supply. Their claw-like nails allow them to cling vertically to the trunks as they jump between trees.

 

Information Sourced from Longleat Guidebook.

© Brian E Kushner

Didelphimoarphi (pronounced /daɪˌdɛlfɨˈmɔrfi.ə/) is the order of common opossums of the Western Hemisphere. They are commonly also called possums, though that term is also applied to Australian fauna of the suborder Phalangeriformes. The Virginia Opossum is the original animal named opossum. The word comes from Algonquian wapathemwa. Opossums probably diverged from the basic South American marsupials in the late Cretaceous or early Paleocene. A sister group is Paucituberculata (shrew opossums).

 

Their unspecialized biology, flexible diet and reproductive strategy make them successful colonizers and survivors in diverse locations and conditions. Originally native to the eastern United States, the Virginia Opossum was intentionally introduced into the West during the Great Depression, probably as a source of food.[2] Its range has been expanding steadily northwards, thanks in part to more plentiful, man-made sources of freshwater, increased shelter due to urban encroachment, and milder winters. Its range has extended into Ontario, Canada, and it has been found farther north than Toronto.

 

Characteristics

 

Didelphimorphs are small to medium-sized marsupials, with the largest about the size of a large house cat, and the smallest the size of a mouse. They tend to be semi-arboreal omnivores, although there are many exceptions. Most members of this taxon have long snouts, a narrow braincase, and a prominent sagittal crest. The dental formula is:

Dentition

5.1.3.4

4.1.3.4

 

By mammalian standards, this is a very full jaw. Opossums have more teeth than any other land mammal; only aquatic mammals have more.[citation needed] The incisors are very small, the canines large, and the molars are tricuspid.

 

Didelphimorphs have a plantigrade stance (feet flat on the ground) and the hind feet have an opposable digit with no claw. Like some New World monkeys, opossums have prehensile tails. The stomach is simple, with a small cecum.

 

Opossums have a remarkably robust immune system, and show partial or total immunity to the venom of rattlesnakes, cottonmouths, and other pit vipers.[3][4] Opossums are about eight times less likely to carry rabies than wild dogs, and about one in eight hundred opossums are infected with this virus.[5]

 

[edit] Reproduction and life cycle

Sleeping Virginia opossum with babies in her relaxed pouch

 

As a marsupial, the opossum has a reproductive system that is composed of a placenta and a marsupium, which is the pouch.[6] The young are born at a very early stage, although the gestation period is similar to many other small marsupials, at only 12 to 14 days.[7] Once born, the offspring must find their way into the marsupium to hold onto and nurse from a teat. The species are moderately sexually dimorphic with males usually being slightly larger, much heavier, and having larger canines than females.[8] The largest difference between the opossum and other mammals is the bifurcated penis of the male and bifurcated vagina of the female (the source of the Latin didelphis, meaning double-wombed). Male opossum spermatozoa exhibit cooperative methods of ensuring the survival of genotypically similar sperm by forming conjugate pairs before fertilization[9] . Such measures come into place particularly when females copulate with multiple males. These conjugate pairs increase motility and enhance the likelihood of fertilization. Conjugate pairs dissociate into separate spermatozoa before fertilization. The opossum is one of many species that employs sperm cooperation in its reproductive life cycle.

 

Female opossums often give birth to very large numbers of young, most of which fail to attach to a teat, although as many as thirteen young can attach[8], and therefore survive, depending on species. The young are weaned between 70 and 125 days, when they detach from the teat and leave the pouch. The opossum lifespan is unusually short for a mammal of its size, usually only two to four years. Senescence is rapid.[10]

 

[edit] Diet

 

Didelphimorphs are opportunistic omnivores with a very broad diet. Their diet mainly consists of carrion and many individual opossums are killed on the highway when scavenging for roadkill. They are also known to eat insects, frogs, birds, snakes, small mammals, and earthworms. Some of their favorite foods are fruits, and they are known to eat apples and persimmons. Their broad diet allows them to take advantage of many sources of food provided by human habitation such as unsecured food waste (garbage) and pet food.

Opossum fur is quite soft.

 

[edit] Behavior

 

Opossums are usually solitary and nomadic, staying in one area as long as food and water are easily available. Some families will group together in ready-made burrows or even under houses. Though they will temporarily occupy abandoned burrows, they do not dig or put much effort into building their own. As nocturnal animals, they favor dark, secure areas. These areas may be below ground or above.

Didelphis marsupialis: intrusion in human dwelling (French Guiana)

 

When threatened or harmed, they will play possum, mimicking the appearance and smell of a sick or dead animal. The lips are drawn back, teeth are bared, saliva foams around the mouth, and a foul-smelling fluid is secreted from the anal glands. The physiological response is involuntary, rather than a conscious act. Their stiff, curled form can be prodded, turned over, and even carried away. The animal will regain consciousness after a period of minutes or hours and escape.

 

Adult opossums do not hang from trees by their tails, though babies may dangle temporarily. Their semi-prehensile tails are not strong enough to support a mature adult's weight. Instead, the opossum uses its tail as a brace and a fifth limb when climbing. The tail is occasionally used as a grip to carry bunches of leaves or bedding materials to the nest. A mother will sometimes carry her young upon her back, where they will cling tightly even when she is climbing or running.

 

Threatened opossums (especially males) will growl deeply, raising their pitch as the threat becomes more urgent. Males make a clicking & smack; noise out of the side of their mouths as they wander in search of a mate, and females will sometimes repeat the sound in return. When separated or distressed, baby opossums will make a sneezing noise to signal their mother. If threatened, the baby will open its mouth and quietly hiss until the threat is gone.

The Virginia opposum is the only North American marsupial.

 

Historical references

 

An early description of the opossum comes from explorer John Smith, who wrote in Map of Virginia, with a Description of the Countrey, the Commodities, People, Government and Religion in 1608 that An Opassom hath an head like a Swine, and a taile like a Rat, and is of the bignes of a Cat. Under her belly she hath a bagge, wherein she lodgeth, carrieth, and sucketh her young.[11][12]. The Opossum was more formally described in 1698 in a published letter entitled Carigueya, Seu Marsupiale Americanum Masculum. Or, The Anatomy of a Male Opossum: In a Letter to Dr Edward Tyson, from Mr William Cowper, Chirurgeon, and Fellow of the Royal Society, London, by Edward Tyson, M. D. Fellow of the College of Physicians and of the Royal Society. The letter suggests even earlier descriptions.[13]

 

[edit] Hunting, food and foodways

 

The opossum was once a favorite game animal in the United States, and in particular the southern regions which have a large body of recipes and folklore relating to the opossum. Opossum was once widely consumed in the United States where available, as evidenced by recipes available online[14] and in books such as older editions of The Joy of Cooking. A traditional method of preparation is baking, sometimes in a pie or pasty[1], though at present possum pie & most often refers to a sweet confection containing no meat of any kind. In Dominica and Trinidad opossum or manicou is popular and can only be hunted during certain times of the year owing to over hunting; the meat is traditionally prepared by smoking then stewing. The meat is light and fine-grained, but the musk glands must be removed as part of preparation. The meat can be used in place of rabbit and chicken in recipes. The cousin of the opossum, the possum, found in Australia (and introduced to New Zealand ) is consumed in a similar manner. [15]

 

Historically, hunters in the Caribbean would place a barrel with fresh or rotten fruit to attract opossums who would feed on the fruit or insects. Cubans growing up in the mid-twentieth century tell of brushing the maggots out of the mouths of manicou caught in this manner to prepare them for consumption. It is said also that the gaminess of the meat causes gas.[citation needed]

 

In Mexico, opossums are known as tlacuache or &tlaquatzin. Their tails are eaten as a folk remedy to improve fertility.

 

Opossum oil (Possum grease) is high in essential fatty acids and has been used as a chest rub and a carrier for arthritis remedies given as topical salves.

Surma or Suri are sedentary pastoral people living in south west of Ethiopia, on the western bank of the Omo River, in the Kibish and Tulgit area.

 

These breeders tribal groups have a cattle centred culture. They grow cabbage, beans, yams, tobacco and coffee and breed their cattle, mostly cows, on their traditional lands, located in the Omo Valley. Cows are tremendously important for the Suris. They do not see cattle simply as a material asset but as a life sustaining and meaningful companion. Suri even sing songs for them and make fires to warm them. These cows are not bred for their meat and are usually not killed unless they are needed for ceremonial purposes. They use their milk and their blood, which they both drink. Cows also have a social and symbolic meaning in Suri’s society. Suri men are judged on how much cattle they own. In desperate times, Suri men can risk their lives to steal cattle from other tribes. The average male in the Suri tribe owns 40 cows. Every young male is named after their cattle, which they have to look after since the age of 8. Cows are given to the bride’s family after the wedding ceremony. Usually 20 cows and they offer also a Kalashnikov as wedding gift.

 

This central role of the cow in their way of life accounts for the fierce independence they want to preserve and explains their warlike culture. Indeed, it’s quite common to see men and even women carrying Kalashnikovs, which are part of the daily life. Their remote homeland has always been a place of traditional rivalries with the neighbouring tribes such as the Bume (Nyangatom) or the Toposa from Sudan who regularly team up to raid the Suri’s cattle. These fights, and even sometimes battles, have become quite bloody since automatic firearms have become available from the parties in the Sudanese Civil War. This conflict has pushed neighbouring tribes into Suri’s land and is a constant competition to keep and protect their territory and owns.

 

Like their neighbours, the Surma also paint their bodies. They create a variety of designs on their necked bodies using their fingertips, which helps them to expose their dark skins. The painting could have both a beautifying and opponent frightening purpose. As one studies these body paintings whirls, stripes, flower and star designs are noticeable. Surma men who are generally believed to be expert artists also paint the girls.

 

A ritual chief in the villages known as the Komoru, dressed in colourful robes and wearing a crown of baboon fur leads the Suri. Village life is largely communal, sharing the produce of the cattle (milk and blood). The men in an assembly take decisions of the village.

Although their traditional remoteness and autarky is threatened, only few Surma are familiar with Amharic, the official language of Ethiopia, and their literacy level is very low. Lip plate and Donga stick fight are the two typical distinctive features of these people, which they share with the neighbouring Mursi people.

 

Suri women wear giant lip plate, a sign of beauty, like in Mursi tribe, and also a prime attraction for tourists which help to sustain a view of them, in guidebooks and travel articles, as an untouched people, living in one of the last wildernesses of Africa. When they are ready to marry, teenagers start to make a hole in the lower lip with a wood stick. It will be kept for one night, and is removed to put a bigger one. This is very painful at this time. Few months after, the lip plate has its full size, and the men see the girl as beautiful. The lip plate is made of wood or terracotta. They have to remove the lower incisors to let some space for the disc. Sometimes the pressure of the plate breaks the lip. This is a big problem for the girl because men will consider her as ugly, she won't be able to marry anyone in the tribe apart the old men or the sick people.

 

The Sagenai, called also donga ritual is a combat that brings both wounds and honor to both the winner and loser. The men bodies are decorated with ritual drawings and their heads are protected by a sort of helmet. For the boys participating to the donga, this challenge is a true moment of glory. The combat is taking place in a middle of a circle made by the crowd. The rules are simple and can be summed up as follows: the person who manages to stay on his feet is the winner, and one must absolutely not kill his opponent. The winner will be honored by the entire tribe and can choose girls to date.

The lands of the Suri are stolen by the Ethiopian government to be rented to foreign companies. A Malaysian company, Lim Slow Jin, runs the Koka plantation near Kibish on the east side of the Omo. The lands are confiscated and rented out for 1 euro per hectare for a year.

© Eric Lafforgue

www.ericlafforgue.com

Again, taken through double glazing, so not the sharpest of shots, sorry!

 

Often weighing over half a kilo and measuring about 23cm, without counting the tail. It has a blunt muzzle, small hair-covered ears and a tail that is shorter than its body.

 

Rats have well developed senses of smell taste and touch. They have an acute sense of hearing, frequently using ultrasound to communicate, and are particularly sensitive to any sudden noise.

 

Rats need to gnaw to keep their constantly growing incisor teeth worn down. They damage woodwork, plastic, bricks and lead pipes, and will strip insulation from electrical cables.

 

Brown Rats live in any situation that provides food, water and shelter. In homes, they will live in roof spaces, wall cavities or under floorboards. In gardens, they will burrow into grassy banks or under sheds.

Twenty years ago today, the Smithsonian’s National Zoo welcomed naked mole-rats (Heterocephalus glaber) into its collection. These rodents, which are more closely related to porcupines and guinea pigs than to their namesake, are one of only a handful of mammals that exhibit eusocial behavior. Like insects such as termites and bees, naked mole-rats follow a hierarchical social structure that consists of one breeding female called the queen, up to three breeding males and many non-breeding workers and soldiers. In the wild, a single colony may contain as few as 20 individuals or as many as 300 individuals.

 

Eleven naked mole-rats are currently on exhibit at the Zoo’s Small Mammal House, though two other colonies, each comprised of nine individuals, live off-exhibit. Nearly 300 naked mole-rat pups have been born here and survived to adulthood since 1991. However, no pups have survived in the last 10 years. For unknown reasons, it is common for captive colonies to self-regulate their population. In the wild and in human care, these animals can live upwards of 30 years old.

 

Naked mole-rats are native to the arid-desert and semi-grassy regions of Ethiopia, Kenya and Somalia in Eastern Africa and spend most of their lives navigating through dark underground tunnels. Because they have poor eyesight, they rely on smell, touch and hearing to get around. Measuring only three inches long, these rodents sport very little hair and have bare, wrinkly skin which varies in color from pink to grayish-pink. In addition to hairy feet, they also have hairy mouths that prevent them from swallowing dirt while they dig with their large incisor teeth.

 

Visitors to the Zoo’s website can watch naked mole-rats on the webcam.

 

# # #

 

Photo Credit: Meghan Murphy, Smithsonian’s National Zoo.

 

Per l'Amore del Maestro, 25 artisti affascinati da Piranesi

Il 2020 ha segnato il tricentenario della nascita di Giovanni Battista Piranesi. L'architetto, antiquario, incisore, vedutista, designer e scrittore italiano è stata una delle personalità artistiche di spicco del 18 ° secolo a Roma. La sua interpretazione del mondo classico è diventata di grande importanza non solo nel 18 ° secolo, ma anche molto tempo dopo la sua morte. L'Ufficio dei Lavori Pubblici (OPW) ospiterà la mostra internazionale For the Love of the Master , 25 artisti affascinati da Piranesi per celebrare l'eredità di questo poliedrico artista romano nel 21 ° secolo.A causa della pandemia di COVID-19 la mostra è stata posticipata e si svolgerà nell'estate del 2022.

  

Felt like some delicious sandwiches. So went all out with avocado, tomato sans bacon. Quite refreshing. A good sandwich is an art form. Wrote a post in my blog (here) Am incisor challenged. Ha. So I dice the toms up a bit. man, I just felt like something "fresh." Paid $1.69 for the avocado... just ripe enough.

Guido Reni

Guido Reni (Bologna, 4 novembre 1575 – Bologna, 18 agosto 1642) è stato un pittore e incisore italiano, uno dei massimi esponenti del classicismo seicentesco.

Biografia

Reni nacque a Bologna nell'attuale Palazzo Ariosti di via San Felice 3 da Daniele, musicista e maestro della Cappella di San Petronio e Ginevra Pozzi; venne battezzato il 7 novembre nella chiesa metropolitana di San Pietro. Un'erronea tradizione che risale alla fine del Settecento lo fa nascere a Calvenzano (Vergato), nell'Appennino bolognese.

 

Nel 1584, a dire dello storico Carlo Cesare Malvasia che conobbe il pittore, abbandonò gli studi di musica a cui era stato avviato dal padre per entrare nell'avviata bottega bolognese del pittore fiammingo Denijs Calvaert, amico del padre, che si impegnò a tenerlo per dieci anni. Ebbe per compagni di apprendistato pittori destinati a grande successo come Francesco Albani e il Domenichino e sappiamo che studiò in particolare le incisioni del Dürer e di Raffaello.

 

Morto il padre il 7 gennaio 1594, Guido lasciò la bottega del Calvaert per aderire all'Accademia degli Incamminati, scuola di pittura fondata dai Carracci nel 1582 col nome di Accademia dei Desiderosi (il nome fu cambiato nel 1590). Qui approfondì la pittura ad olio, l'incisione a bulino (riproducendo ad esempio l'Elemosina di San Rocco di Annibale) e copiando a più riprese singole parti dell'Estasi di Santa Cecilia, allora esposta nella chiesa di San Giovanni in Monte.

 

Qui mostrò il suo talento: il Malvasia riferisce l'aneddoto del suggerimento dato da Annibale a Ludovico Carracci, di non gl'insegnar tanto a costui, che un giorno ne saprà più di tutti noi. Non vedi tu come non mai contento, egli cerca cose nuove? Raccordati, Lodovico, che costui un giorno ti vuol far sospirare.

 

Nel 1598, già pittore indipendente, dipinse la Incoronazione della Vergine e quattro santi, oggi nella Pinacoteca di Bologna, per la chiesa di San Bernardo, e vinse la gara, in concorrenza con Ludovico Carracci, per la decorazione della facciata del Palazzo del Reggimento, l'attuale palazzo municipale di Bologna: gli affreschi, commissionati per onorare la visita di papa Clemente VIII (di passaggio in occasione della devoluzione del Ducato di Ferrara allo Stato della Chiesa) e rappresentanti figure allegoriche, si erano già cancellati nell'Ottocento e rappresentarono la rottura con il suo vecchio maestro e con altri allievi dei Carracci. Sono contemporanee le tele della Madonna col Bambino, san Domenico e i Misteri del Rosario della Basilica di San Luca, due affreschi in palazzo Zani a Bologna e, tra diversi altri lavori, l'Assunzione della Vergine nella parrocchiale di Pieve di Cento. Il 5 dicembre 1599 entrò nel Consiglio della Congregazione dei pittori di Bologna.

 

La figura di Guido Reni è stata ripresa anche dallo scrittore tedesco Joseph von Eichendorff nel suo romanzo Aus dem Leben eines Taugenichts, vita di un perdigiorno.

A Roma

Forse già nel 1600 ma certamente nel 1601 era a Roma, dove l'11 ottobre fu pagato dal cardinale Sfondrato per il suo Martirio di santa Cecilia della Basilica di Santa Cecilia in Trastevere: per lo stesso committente e la stessa chiesa eseguì anche l'Incoronazione dei santi Cecilia e Valeriano e una copia - questa volta intera - del dipinto bolognese di Raffaello, l'Estasi di Santa Cecilia con quattro santi, ora nella chiesa di San Luigi dei Francesi e dipinta a Bologna prima della partenza. Nel marzo del 1602 tornò nella città natale per assistere ai funerali del grande Agostino Carracci e fu incaricato di incidere a stampa le decorazioni allestite per il funerale.

 

Viaggiò da Bologna a Roma e di qui a Loreto, per trattare delle eventuali decorazioni della Santa Casa che furono però affidate al Pomarancio.

 

In questo periodo dipinse il Cristo in Pietà adorato dai santi Vittore e Corona, da Santa Tecla e San Diego d'Alcalà, ora nella Cappella della Sacra Spina del Duomo di Osimo (1601 circa) e la Trinità con la Madonna di Loreto (1604) per la Chiesa della Trinità o del Sacramento della stessa cittadina. Entrambe le opere furono richieste dal cardinale Antonio Maria Galli, un creato di Sisto V, noto in ambito storico artistico per le sue commissioni al pittore Cristoforo Roncalli, il Pomarancio.

 

Nel 1605 completò La crocefissione di san Pietro, per la chiesa romana di San Paolo alle Tre Fontane, ora nella Pinacoteca Vaticana, commissionatagli dal cardinale Pietro Aldobrandini. Per il Malvasia sarebbe stato il Cavalier d'Arpino a suggerire l'emulazione del soggetto, derivato dalla tela caravaggesca della basilica di Santa Maria del Popolo, per danneggiare il Caravaggio nei favori dei committenti. Ne riprodusse in parte i contrasti di luce ma tolse il dramma: la sua crocefissione è un tranquillo lavoro di artigiani, che rovesciano un santo rassegnato sulla croce e lo legano e l'inchiodano con gesti lenti e metodici.

 

È la sua ricerca del bello ideale, ricavato dal classicismo raffaellesco nella mediazione dei Carracci che sfiora soltanto la visione naturalistica di Caravaggio ma se ne allontana per la necessità di ammantarla di decoro; di questa esperienza, nel primo decennio del secolo, sono parte il Davide con la testa di Golia del Louvre, il Martirio di santa Caterina per la chiesa di Sant'Alessandro a Conscente, ora al Museo diocesano di Albenga in Liguria, La preghiera nell'orto di Sens e L'incoronazione della Vergine di Londra.

La sua fama è così consolidata che nel 1608 papa Paolo V gli affidò la decorazione di due sale dei Palazzi Vaticani, la Sala delle Nozze Aldobrandine e la Sala delle Dame, e il cardinale Borgherini gli affreschi di San Gregorio al Celio, il Martirio di sant'Andrea e l'Eterno in gloria. L'anno dopo iniziò la decorazione della cappella dell'Annunciata nel palazzo del Quirinale, avvalendosi dell'aiuto di Francesco Albani, Antonio Carracci, Jacopo Cavedone, Tommaso Campana, ma soprattutto Giovanni Lanfranco; l'iscrizione di termine dei lavori reca la data 1610, comprendendo gli affreschi sulle pareti e la tavola dell'Annunciazione sull'altare, "con maggior applauso e meraviglia di tutta la Corte, che vi accorse ad ammirarla come cosa prodigiosa" (Malvasia).

 

Il 25 settembre 1609 ricevette il primo acconto per gli affreschi della cappella Paolina in Santa Maria Maggiore che interruppe alla fine del 1610, sembra per contrasti con l'amministrazione papale. Tornò a Bologna dopo il 1614, anno in cui terminò l'Aurora per il casino Rospigliosi (a Roma). La Strage degli innocenti e il Sansone vittorioso furono probabilmente iniziati a Roma e terminati a Bologna (venti scudi gli erano infatti anticipati a Roma per la commissione della Strage).

 

Se il Sansone è un gigante effeminato che si ristora dopo il massacro, e i morti sembrano dormire placidamente nella serenità albeggiante di una vasta pianura, nell'altra Strage, rappresentata con sei donne, due piccoli morti e due assassini, la tragedia è congelata nella misura e nella simmetria della composizione raffaellesca. Di questo dipinto, suo capolavoro assoluto, si ricordarono Poussin, i pittori neoclassici francesi e persino Picasso, che richiamò la tela di Reni in alcune parti del suo Guernica.

 

Tornò a Roma nel 1612, per terminare in aprile gli affreschi di Santa Maria Maggiore; il cardinale Scipione Borghese gli commissionò, per un Casino nel parco del suo palazzo, ora Palazzo Pallavicini Rospigliosi, l'affresco dell'Aurora, terminato nell'agosto 1614. Il grandioso affresco ebbe grande fortuna fino al Neoclassicismo: il carro di Apollo, circondato dalle figure delle Ore è preceduto dall'Aurora mentre sopra i quattro cavalli vola Fosforo, l'astro del mattino, con una torcia accesa; in basso a destra un paesaggio marino.

 

Dopo un breve soggiorno a Napoli, ancora a Roma ai primi del 1614, tornò definitivamente a Bologna nell'ottobre 1614.

 

Al primo viaggio di ritorno da Roma, e ai dubbi sulla sua pittura, è dedicato il romanzo biografico Il viaggio di Guido Reni, scritto da Manlio Cancogni e vincitore del Premio Grinzane Cavour del 1987 (Lit, Roma, 2013).

 

Da Wikipedia, l'enciclopedia libera.

Elephants are large mammals of the family Elephantidae and the order Proboscidea. Traditionally, two species are recognised, the African elephant (Loxodonta africana) and the Asian elephant (Elephas maximus), although some evidence suggests that African bush elephants and African forest elephants are separate species (L. africana and L. cyclotis respectively). Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia. Elephantidae are the only surviving family of the order Proboscidea; other, now extinct, families of the order include mammoths and mastodons. Male African elephants are the largest surviving terrestrial animals and can reach a height of 4 m (13 ft) and weigh 7,000 kg (15,000 lb). All elephants have several distinctive features the most notable of which is a long trunk or proboscis, used for many purposes, particularly breathing, lifting water and grasping objects. Their incisors grow into tusks, which can serve as weapons and as tools for moving objects and digging. Elephants' large ear flaps help to control their body temperature. African elephants have larger ears and concave backs while Asian elephants have smaller ears and convex or level backs.

 

Elephants are herbivorous and can be found in different habitats including savannahs, forests, deserts and marshes. They prefer to stay near water. They are considered to be keystone species due to their impact on their environments. Other animals tend to keep their distance, and predators such as lions, tigers, hyenas and wild dogs usually target only the young elephants (or "calves"). Females ("cows") tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups are led by an individual known as the matriarch, often the oldest cow. Elephants have a fission-fusion society in which multiple family groups come together to socialise. Males ("bulls") leave their family groups when they reach puberty, and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate and enter a state of increased testosterone and aggression known as musth, which helps them gain dominance and reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness and show empathy for dying or dead individuals of their kind.

 

African elephants are listed as vulnerable by the International Union for Conservation of Nature (IUCN), while the Asian elephant is classed as endangered. One of the biggest threats to elephant populations is the ivory trade, as the animals are poached for their ivory tusks. Other threats to wild elephants include habitat destruction and conflicts with local people. Elephants are used as working animals in Asia. In the past they were used in war; today, they are often put on display in zoos and circuses. Elephants are highly recognisable and have been featured in art, folklore, religion, literature and popular culture.

 

(Wikipedia)

 

-----

 

We traveled rather long way from Kandy to Haputale during our third day in Sri Lanka and enjoyed local traffic quite heavily - transportation of elephants is really no problem in Sri Lanka :-).

South Africa.

Kruger Park.

Game Drive in open jeep.

 

WATCH THE VIDEO

 

Body stripes are less numerous and broader than that of the Cape Mountain Zebra, whereas body stripes extend around the belly. Leg striping is less prominent. Measures 1.3 to 1.4 metres at the shoulder and weighs 300-320 Kg. They have rounded ears approximately 160-170 mm long. Front portion of mane forms a black tuft between the ears. Diet: Predominantly a grazer, feeding in areas with short grass. Zebra have a strong sensitive upper lip with which it gathers herbage by collecting the grass between the lip and the lower incisors before plucking the harvest.

www.krugerpark.co.za/africa_burchells_zebra.html

While the pandas are very cute, they are bears, with teeth made for ripping and tearing. Note the big incisors for gripping prey.

BIG5 Elephant. Welgevonden Game Reserve. South Africa. Feb/2021

 

Elephant

Elephants are large mammals of the family Elephantidae and the order Proboscidea. Three species are currently recognised: the African bush elephant (Loxodonta africana), the African forest elephant (L. cyclotis), and the Asian elephant (Elephas maximus). Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia. Elephantidae is the only surviving family of the order Proboscidea; other, now extinct, members of the order include deinotheres, gomphotheres, mammoths, and mastodons.

All elephants have several distinctive features, the most notable of which is a long trunk (also called a proboscis), used for many purposes, particularly breathing, lifting water, and grasping objects. Their incisors grow into tusks, which can serve as weapons and as tools for moving objects and digging. Elephants' large ear flaps help to control their body temperature. Their pillar-like legs can carry their great weight. African elephants have larger ears and concave backs while Asian elephants have smaller ears and convex or level backs.

Elephants are herbivorous and can be found in different habitats including savannahs, forests, deserts, and marshes. They prefer to stay near water. They are considered to be a keystone species due to their impact on their environments. Other animals tend to keep their distance from elephants while predators, such as lions, tigers, hyenas, and any wild dogs, usually target only young elephants (or "calves"). Elephants have a fission–fusion society in which multiple family groups come together to socialise. Females ("cows") tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups are led by an individual known as the matriarch, often the oldest cow.

Males ("bulls") leave their family groups when they reach puberty and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate and enter a state of increased testosterone and aggression known as musth, which helps them gain dominance and reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell, and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness and show empathyfor dying or dead individuals of their kind.

Source: Wikipedia

Elefante

Os elefantes são animais herbívoros, alimentando-se de ervas, gramíneas, frutas e folhas de árvores. Dado o seu tamanho, um elefante adulto pode ingerir entre 70 a 150 kg de alimentos por dia. As fêmeas vivem em manadas de 10 a 15 animais, lideradas por uma matriarca, compostas por várias reprodutoras e crias de variadas idades. O período de gestação das fêmeas é longo (20 a 22 meses), assim como o desenvolvimento do animal que leva anos a atingir a idade adulta. Os filhotes podem nascer com 90 kg. Os machos adolescentes tendem a viver em pequenos bandos e os machos adultos isolados, encontrando-se com as fêmeas apenas no período reprodutivo.

Devido ao seu porte, os elefantes têm poucos predadores. Exercem uma forte influência sobre as savanas, pois mantêm árvores e arbustos sob controle, permitindo que pastagens dominem o ambiente. Eles vivem cerca de 60 anos e morrem quando seus molares caem, impedindo que se alimentem de plantas.

Os elefantes-africanos são maiores que as variedades asiáticas e têm orelhas mais desenvolvidas, uma adaptação que permite libertar calor em condições de altas temperaturas. Outra diferença importante é a ausência de presas de marfim nas fêmeas dos elefantes asiáticos.

Durante a época de acasalamento, o aumento da produção de testosterona deixa os elefantes extremamente agressivos, fazendo-os atacar até humanos. Acidentes com elefantes utilizados em rituais geralmente são causados por esse motivo. Cerca de 400 humanos são mortos por elefantes a cada ano.

Elefante é o termo genérico e popular pelo qual são denominados os membros da família Elephantidae, um grupo de mamíferos proboscídeoselefantídeos, de grande porte, do qual há três espécies no mundo atual, duas africanas (Loxodonta sp.) e uma asiática (Elephas sp.). Há ainda os mamutes (Mammuthus sp.), hoje extintos. Até recentemente, acreditava-se que havia apenas duas espécies vivas de elefantes, o elefante-africano e o elefante-asiático, uma espécie menor. Entretanto, estudos recentes de DNA sugerem que havia, na verdade, duas espécies de elefante-africano: Loxodonta africana, da savana, e Loxodonta cyclotis, que vive nas florestas. Os elefantes são os maiores animais terrestres da actualidade, com a massa entre 4 a 6 toneladas e medindo em média quatro metros de altura, podem levantar até 10.000 kg. As suas características mais distintivas são as presas de marfim

Fonte: Wikipedia

  

Welgevonden Game Reserve

 

Welgevonden Game Reserve, (Dutch for well found), is in the Waterberg District, of the Limpopo, province of South Africa. Welgevonden Game Reserve, (Dutch for "well found"), is a 38,200ha game reserve in the Waterberg District, of the Limpopo Province of South Africa.

It forms part of the Waterberg Biosphere Reserve which was officially declared by UNESCO in 2001 and currently covers an area in excess of 654,033 hectare.

The reserve comprises mountainous terrain that is dissected by deep valleys and kloofs while flat plateaus characterise most hilltops. Altitude varies from 1080 m in the north to ±1800 m in the southern section of the reserve.

Welgevonden is home to over 50 different mammals, including the Big Five. The diversity of habitat leads to a wide range of wildlife with grassy plains abounding with antelope from the largest eland to the diminutive duiker; and cheetah, lion and leopard are regularly seen close by. There are also numerous rare and unusual species such as brown hyena, aardwolf, pangolin and aardvark – all best seen at night. Over 300 bird species can be seen on the reserve, including rare blue cranes which breed in the southern section early in the year.

Source: Wikipedia

Reserva Welgevonden

A Welgevonden Game Reserve, (holandês para bem encontrado), fica no distrito de Waterberg, no Limpopo, província da África do Sul. Welgevonden Game Reserve, (holandês para "bem encontrado"), é uma reserva de safari de 38.200 hectares no distrito de Waterberg, na província de Limpopo da África do Sul.

Faz parte da Reserva da Biosfera de Waterberg que foi oficialmente declarada pela UNESCO em 2001 e atualmente cobre uma área superior a 654.033 hectares.

A reserva compreende terrenos montanhosos que são dissecados por vales profundos e kloofs, enquanto planaltos planos caracterizam a maioria dos topos das colinas. A altitude varia de 1080 m no norte a ± 1800 m na seção sul da reserva.

Welgevonden é o lar de mais de 50 mamíferos diferentes, incluindo os Big Five. A diversidade de habitat leva a uma grande variedade de vida selvagem com planícies gramíneas repletas de antílopes, desde o maior elã até o diminuto duiker; e chita, leão e leopardo são vistos regularmente por perto. Existem também numerosas espécies raras e incomuns, como hiena marrom, aardwolf, pangolin e aardvark - todos melhor vistos à noite. Mais de 300 espécies de pássaros podem ser vistas na reserva, incluindo o Grou-do-paraíso que se reproduzem na seção sul no início do ano.

Fonte: Wikipedia (tradução livre)

 

BIG5. Elephant. Kruger National Park. Kruger Shalati: The Train on the Bridge. South Africa. May/2021

 

Elephant

Elephants are large mammals of the family Elephantidae and the order Proboscidea. Three species are currently recognised: the African bush elephant (Loxodonta africana), the African forest elephant (L. cyclotis), and the Asian elephant (Elephas maximus). Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia. Elephantidae is the only surviving family of the order Proboscidea; other, now extinct, members of the order include deinotheres, gomphotheres, mammoths, and mastodons.

All elephants have several distinctive features, the most notable of which is a long trunk (also called a proboscis), used for many purposes, particularly breathing, lifting water, and grasping objects. Their incisors grow into tusks, which can serve as weapons and as tools for moving objects and digging. Elephants' large ear flaps help to control their body temperature. Their pillar-like legs can carry their great weight. African elephants have larger ears and concave backs while Asian elephants have smaller ears and convex or level backs.

Elephants are herbivorous and can be found in different habitats including savannahs, forests, deserts, and marshes. They prefer to stay near water. They are considered to be a keystone species due to their impact on their environments. Other animals tend to keep their distance from elephants while predators, such as lions, tigers, hyenas, and any wild dogs, usually target only young elephants (or "calves"). Elephants have a fission–fusion society in which multiple family groups come together to socialise. Females ("cows") tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups are led by an individual known as the matriarch, often the oldest cow.

Males ("bulls") leave their family groups when they reach puberty and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate and enter a state of increased testosterone and aggression known as musth, which helps them gain dominance and reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell, and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness and show empathyfor dying or dead individuals of their kind.

Source: Wikipedia

Elefante

Os elefantes são animais herbívoros, alimentando-se de ervas, gramíneas, frutas e folhas de árvores. Dado o seu tamanho, um elefante adulto pode ingerir entre 70 a 150 kg de alimentos por dia. As fêmeas vivem em manadas de 10 a 15 animais, lideradas por uma matriarca, compostas por várias reprodutoras e crias de variadas idades. O período de gestação das fêmeas é longo (20 a 22 meses), assim como o desenvolvimento do animal que leva anos a atingir a idade adulta. Os filhotes podem nascer com 90 kg. Os machos adolescentes tendem a viver em pequenos bandos e os machos adultos isolados, encontrando-se com as fêmeas apenas no período reprodutivo.

Devido ao seu porte, os elefantes têm poucos predadores. Exercem uma forte influência sobre as savanas, pois mantêm árvores e arbustos sob controle, permitindo que pastagens dominem o ambiente. Eles vivem cerca de 60 anos e morrem quando seus molares caem, impedindo que se alimentem de plantas.

Os elefantes-africanos são maiores que as variedades asiáticas e têm orelhas mais desenvolvidas, uma adaptação que permite libertar calor em condições de altas temperaturas. Outra diferença importante é a ausência de presas de marfim nas fêmeas dos elefantes asiáticos.

Durante a época de acasalamento, o aumento da produção de testosterona deixa os elefantes extremamente agressivos, fazendo-os atacar até humanos. Acidentes com elefantes utilizados em rituais geralmente são causados por esse motivo. Cerca de 400 humanos são mortos por elefantes a cada ano.

Elefante é o termo genérico e popular pelo qual são denominados os membros da família Elephantidae, um grupo de mamíferos proboscídeoselefantídeos, de grande porte, do qual há três espécies no mundo atual, duas africanas (Loxodonta sp.) e uma asiática (Elephas sp.). Há ainda os mamutes (Mammuthus sp.), hoje extintos. Até recentemente, acreditava-se que havia apenas duas espécies vivas de elefantes, o elefante-africano e o elefante-asiático, uma espécie menor. Entretanto, estudos recentes de DNA sugerem que havia, na verdade, duas espécies de elefante-africano: Loxodonta africana, da savana, e Loxodonta cyclotis, que vive nas florestas. Os elefantes são os maiores animais terrestres da actualidade, com a massa entre 4 a 6 toneladas e medindo em média quatro metros de altura, podem levantar até 10.000 kg. As suas características mais distintivas são as presas de marfim

Fonte: Wikipedia

  

Kruger Shalati

Kruger Shalati: The Train on the Bridge. One of the most anticipated and exciting new offerings coming to the iconic Kruger National Park, South Africa. A perfect combination of Africa’s most breathtaking natural splendours with well-deserved luxuries aboard a newly refurbished train that’s reminiscent of African excellence.

Permanently stationed on the historically-rich Selati Bridge above the Sabie River, Kruger Shalati will offer the most unique luxury accommodation in a re-envisioned train which will pay homage to the guests who explored the park nearly 100 years ago while welcoming new explorers from near and far. The train celebrates where the first visits to the iconic park were allowed in the early 1920s, the train would park overnight in the exact spot where Kruger Shalati will be positioned.

Offering 31 rooms, consisting of 24 carriage rooms and 7 Bridge House rooms, all of which will provide a deeply visceral experience, tailored for immersive comfort. Whether you’re looking for a one-of-a-kind adventure, an enthralling break or to simply immerse yourself in earth’s finest creations, Kruger Shalati looks forward to welcoming you on a journey of discovery with nature in the most extraordinary way imaginable.

Source: www.krugershalati.com

Kruger Shalati: O trem na ponte. Uma das novas ofertas mais esperadas e emocionantes que chegam ao icônico Parque Nacional Kruger, na África do Sul. Uma combinação perfeita dos esplendores naturais mais deslumbrantes da África com luxos bem merecidos a bordo de um trem recém-reformado que lembra a excelência africana.

Permanentemente estacionado na histórica Ponte Selati acima do Rio Sabie, Kruger Shalati oferecerá a acomodação de luxo mais exclusiva em um trem reformulado que homenageará os hóspedes que exploraram o parque há quase 100 anos, enquanto recebe novos exploradores. O trem celebra onde as primeiras visitas ao parque icônico foram permitidas no início dos anos 1920, o trem estacionaria durante a noite no local exato onde Kruger Shalati será posicionado.

Oferecendo 31 quartos, consistindo de 24 quartos de carruagem e 7 quartos Bridge House, todos os quais proporcionarão uma experiência profundamente visceral, adaptada para um conforto imersivo. Esteja você procurando por uma aventura única, uma pausa cativante ou simplesmente mergulhar nas melhores criações da terra, Kruger Shalati espera recebê-lo em uma jornada de descoberta com a natureza da maneira mais extraordinária que se possa imaginar.

Fonte: www.krugershalati.com (tradução livre)

 

Kruger National Park

Kruger National Park is one of the largest game reserves in Africa. It covers an area of around 20,000 square kilometres in the provinces of Limpopo and Mpumalanga in northeastern South Africa, and extends 360 kilometres (220 mi) from north to south and 65 kilometres (40 mi) from east to west.

Source: Wikipedia

Parque Nacional Kruger

O Parque Nacional Kruger é a maior área protegida de fauna bravia da África do Sul, cobrindo cerca de 20 000 km2. Está localizado no nordeste do país, nas províncias de Mpumalanga e Limpopo e tem uma extensão de cerca de 360 km de norte a sul e 65 km de leste a oeste.

Os parques nacionais africanos, nas regiões da savana africana são importantes pelo turismo com safári de observação e fotográfico.

O seu nome foi dado em homenagem a Stephanus Johannes Paul Kruger, último presidente da República Sul-Africana bôere. Foi criado em 31 de Maio de 1926

Fonte: Wikipedia

 

Your comments/favs are the highest reward, and very much appreciated.

 

The Red Ruffed Lemur (Varecia rubra) is one of two species in the genus Varecia, the ruffed lemurs; the other is the Black-and-white Ruffed Lemur (Varecia variegata). Like all lemurs, it is native to Madagascar and occurs only in the rainforests of Masoala, in the northeast of the island. It is one of the largest primates of Madagascar with a body length of 53 cm, a tail length of 60 cm and a weight of 3.5–4 kg. Its soft, thick fur is red and black in colour but a few are known to have a white or pink patch on the back of the neck and a ring on the base of the tail in a similar color.

 

There is also another species of ruffed lemur that is similar to the Red Ruffed Lemur; the Black-and-white Ruffed Lemur. They both live in the rainforest along the east coast of Madagascar, but they don't associate with each other.

 

The Red Ruffed Lemur is a very clean animal and spends a lot of time grooming itself and each other. The lower incisors (front teeth) and the claw on the second toe of the hind foot are specially adapted for this behavior. The lower incisors grow forward in line with each other and are slightly spaced. This creates a toothcomb which can be used to groom its long, soft fur. The claw is also used for grooming.

 

The Red Ruffed Lemur lives 15–20 years in the wild. In captivity, 25 years is not uncommon, and one lived to be about 33 years old. It is a diurnal animal, and most active in the morning and evening.

 

[ Source: en.wikipedia.org/wiki/Red_Ruffed_Lemur ]

Near endemic to the South Luangwa valley. The Crawshay's zebra (Equus quagga crawshayi) is a subspecies of the plains zebra. It is native to eastern Zambia, east of the Luangwa River, Malawi, southeastern Tanzania and northern Mozambique south to the Gorongoza District. Crawshay's zebras can be distinguished from other subspecies of plains zebras in that its lower incisors lack an infundibulum. The Crawshay's zebra has very narrow stripes compared to other forms of the Plains zebra.

This youngster, walking across the road to finally join his family who had crossed a few minutes earlier, just looked like a stroppy teenager to us. He looked like he could just have been dragging his feet, with hands stuffed deep in his pockets, huffing as he went along!

 

Elephants are large mammals of the family Elephantidae and the order Proboscidea. Two species are traditionally recognised, the African elephant (Loxodonta africana) and the Asian elephant (Elephas maximus), although some evidence suggests that African bush elephants and African forest elephants are separate species (L. africana and L. cyclotis respectively). Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia. Elephantidae is the only surviving family of the order Proboscidea; other, now extinct, members of the order include deinotheres, gomphotheres, mammoths, and mastodons. Male African elephants are the largest extant terrestrial animals and can reach a height of 4 m (13 ft) and weigh 7,000 kg (15,000 lb). All elephants have several distinctive features the most notable of which is a long trunk or proboscis, used for many purposes, particularly breathing, lifting water and grasping objects. Their incisors grow into tusks, which can serve as weapons and as tools for moving objects and digging. Elephants' large ear flaps help to control their body temperature. Their pillar-like legs can carry their great weight. African elephants have larger ears and concave backs while Asian elephants have smaller ears and convex or level backs.

 

Elephants are herbivorous and can be found in different habitats including savannahs, forests, deserts and marshes. They prefer to stay near water. They are considered to be keystone species due to their impact on their environments. Other animals tend to keep their distance where predators such as lions, tigers, hyenas, and wild dogs usually target only the young elephants (or "calves"). Females ("cows") tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups are led by an individual known as the matriarch, often the oldest cow. Elephants have a fission–fusion society in which multiple family groups come together to socialise. Males ("bulls") leave their family groups when they reach puberty, and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate and enter a state of increased testosterone and aggression known as musth, which helps them gain dominance and reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness and show empathy for dying or dead individuals of their kind.

 

Despite their name, the springhare, or the springhaas, is not a hare or lagomorph, but an anomaluromorph rodent in the family Petetidae. Although springhares are highly hystricomorphous, with a greatly englarged infraorbital foramen (large hole anterior to the orbit above, which serves as an attatchment site for the medial masseter muscle), they are more closely related to the strange scaly-tailed squirrels (Anomaluridae) than to Hysticomorpha (which includes the porcupines, capybaras, guinea pigs, chinchillas, among many others). Springhares are highly convergent to rabbits and hares, both superficially with their saltatorial locomotion (jumping behavior), large hind feet, and elongated ears, but also in some of the fine details of the skull, such as a highly reduced temporalis muscle with a small to nonexistent coronoid process on the mandible (blocked by the zygomatic arch here, but you can tell it doesn't extend upward very high, and notice how small the area is for insertion of the temporalis on the skull compared with most mammals). Massively enlarged auditory bullae (the inflated bones in the back of the skull that house the ear bones) are indicators of the jumping lifestyle, and are seen in other rodent jumpers such as jerboas (Dipodidae), kangaroo rats (Heteromyidae), and the vischachas and chinchillas (Chinchillidae).

 

Despite the fact that I cited one of the similarities between true hares and springhares as jumping, the type of saltatorial locomotion they practice is distinctly different. Springhares jump like the previous groups of rodents I mentioned (jerboas, kangaroo rats) and macropods (true kangaroos), in that they hop bipedally consecutively before allowing their forelimbs to touch the ground again, and usually can remain in a bipedal position indefinitely, and are not obligated to stand quadrupedally, like hares and rabbits are (although I'm sure a hare or rabbit could manage stand up right for a while, but then again, so could my pet dashund). Hares and rabbits are more like anurans (frogs, toads, etc.), in that they can jump well, but must land on all fours before jumping again (Pumas are the cat analog of this behavior, in a sense, as they're hind legs are more proportionately longer than their forelegs than any other cat, and they leap rather well).

 

To see their living cuteness (and they are very very cute), see: animaldiversity.ummz.umich.edu/site/resources/lazette_gif...

 

Or to see some beautiful CT cut-aways of one of these skulls, see: www.digimorph.org/specimens/Pedetes_capensis/

Elephants are large mammals of the family Elephantidae and the order Proboscidea. Three species are currently recognised: the African bush elephant (Loxodonta africana), the African forest elephant (L. cyclotis), and the Asian elephant (Elephas maximus). Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia. Elephantidae is the only surviving family of the order Proboscidea; other, now extinct, members of the order include deinotheres, gomphotheres, mammoths, and mastodons.

 

All elephants have several distinctive features, the most notable of which is a long trunk (also called a proboscis), used for many purposes, particularly breathing, lifting water, and grasping objects. Their incisors grow into tusks, which can serve as weapons and as tools for moving objects and digging. Elephants' large ear flaps help to control their body temperature. Their pillar-like legs can carry their great weight. African elephants have larger ears and concave backs while Asian elephants have smaller ears and convex or level backs.

 

Elephants are herbivorous and can be found in different habitats including savannahs, forests, deserts, and marshes. They prefer to stay near water. They are considered to be keystone species due to their impact on their environments. Other animals tend to keep their distance from elephants while predators, such as lions, tigers, hyenas, and any wild dogs, usually target only young elephants (or "calves"). Elephants have a fission–fusion society in which multiple family groups come together to socialise. Females ("cows") tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups are led by an individual known as the matriarch, often the oldest cow.

 

Males ("bulls") leave their family groups when they reach puberty and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate and enter a state of increased testosterone and aggression known as musth, which helps them gain dominance and reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell, and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness and show empathy for dying or dead individuals of their kind.

 

African elephants are listed as vulnerable by the International Union for Conservation of Nature (IUCN) while the Asian elephant is classed as endangered. One of the biggest threats to elephant populations is the ivory trade, as the animals are poached for their ivory tusks. Other threats to wild elephants include habitat destruction and conflicts with local people. Elephants are used as working animals in Asia. In the past, they were used in war; today, they are often controversially put on display in zoos, or exploited for entertainment in circuses. Elephants are highly recognisable and have been featured in art, folklore, religion, literature, and popular culture.

 

ETYMOLOGY

The word "elephant" is based on the Latin elephas (genitive elephantis) ("elephant"), which is the Latinised form of the Greek ἐλέφας (elephas) (genitive ἐλέφαντος (elephantos)), probably from a non-Indo-European language, likely Phoenician. It is attested in Mycenaean Greek as e-re-pa (genitive e-re-pa-to) in Linear B syllabic script. As in Mycenaean Greek, Homer used the Greek word to mean ivory, but after the time of Herodotus, it also referred to the animal. The word "elephant" appears in Middle English as olyfaunt (c.1300) and was borrowed from Old French oliphant (12th century). Loxodonta, the generic name for the African elephants, is Greek for "oblique-sided tooth".

 

TAXONOMY

CLASSIFICATION, SPECIES AND SUBSPECIES

Elephants belong to the family Elephantidae, the sole remaining family within the order Proboscidea which belongs to the superorder Afrotheria. Their closest extant relatives are the sirenians (dugongs and manatees) and the hyraxes, with which they share the clade Paenungulata within the superorder Afrotheria. Elephants and sirenians are further grouped in the clade Tethytheria. Three species of elephants are recognised; the African bush elephant (Loxodonta africana) and forest elephant (Loxodonta cyclotis) of sub-Saharan Africa, and the Asian elephant (Elephas maximus) of South and Southeast Asia. African elephants have larger ears, a concave back, more wrinkled skin, a sloping abdomen, and two finger-like extensions at the tip of the trunk. Asian elephants have smaller ears, a convex or level back, smoother skin, a horizontal abdomen that occasionally sags in the middle and one extension at the tip of the trunk. The looped ridges on the molars are narrower in the Asian elephant while those of the African are more diamond-shaped. The Asian elephant also has dorsal bumps on its head and some patches of depigmentation on its skin. In general, African elephants are larger than their Asian cousins.

 

Swedish zoologist Carl Linnaeus first described the genus Elephas and an elephant from Sri Lanka (then known as Ceylon) under the binomial Elephas maximus in 1758. In 1798, Georges Cuvier classified the Indian elephant under the binomial Elephas indicus. Dutch zoologist Coenraad Jacob Temminck described the Sumatran elephant in 1847 under the binomial Elephas sumatranus. English zoologist Frederick Nutter Chasen classified all three as subspecies of the Asian elephant in 1940. Asian elephants vary geographically in their colour and amount of depigmentation. The Sri Lankan elephant (Elephas maximus maximus) inhabits Sri Lanka, the Indian elephant (E. m. indicus) is native to mainland Asia (on the Indian subcontinent and Indochina), and the Sumatran elephant (E. m. sumatranus) is found in Sumatra. One disputed subspecies, the Borneo elephant, lives in northern Borneo and is smaller than all the other subspecies. It has larger ears, a longer tail, and straighter tusks than the typical elephant. Sri Lankan zoologist Paules Edward Pieris Deraniyagala described it in 1950 under the trinomial Elephas maximus borneensis, taking as his type an illustration in National Geographic. It was subsequently subsumed under either E. m. indicus or E. m. sumatranus. Results of a 2003 genetic analysis indicate its ancestors separated from the mainland population about 300,000 years ago. A 2008 study found that Borneo elephants are not indigenous to the island but were brought there before 1521 by the Sultan of Sulu from Java, where elephants are now extinct.

 

The African elephant was first named by German naturalist Johann Friedrich Blumenbach in 1797 as Elephas africanus. The genus Loxodonta was named by Frédéric Cuvier in 1825. Cuvier spelled it Loxodonte, but in 1827 an anonymous author romanised the spelling to Loxodonta; the International Code of Zoological Nomenclature recognises this as the proper authority. In 1942, 18 subspecies of African elephant were recognised by Henry Fairfield Osborn, but further morphological data has reduced the number of classified subspecies, and by the 1990s, only two were recognised, the savannah or bush elephant (L. a. africana) and the forest elephant (L. a. cyclotis), the latter having been named in 1900 by German zoologist Paul Matschie. Forest elephants have smaller and more rounded ears and thinner and straighter tusks than bush elephants, and are limited in range to the forested areas of western and Central Africa. A 2000 study argued for the elevation of the two forms into separate species (L. africana and L. cyclotis respectively) based on differences in skull morphology. DNA studies published in 2001 and 2007 also suggested they were distinct species while studies in 2002 and 2005 concluded that they were the same species. Further studies (2010, 2011, 2015) have supported African savannah and forest elephants' status as separate species. The two species are believed to have diverged 6 million years ago. and have been completely genetically isolated for the past 500,000 years. In 2017, DNA sequence analysis showed that L. cyclotis is more closely related to the extinct Palaeoloxodon antiquus, than it is to L. africana, possibly undermining the genus Loxodonta as a whole. Some evidence suggests that elephants of western Africa are a separate species, although this is disputed. The pygmy elephants of the Congo Basin, which have been suggested to be a separate species (Loxodonta pumilio) are probably forest elephants whose small size and/or early maturity are due to environmental conditions.

 

EVOLUTION AND EXTINCT RELATIVES

Over 185 extinct members and three major evolutionary radiations of the order Proboscidea have been recorded. The earliest proboscids, the African Eritherium and Phosphatherium of the late Paleocene, heralded the first radiation. The Eocene included Numidotherium, Moeritherium, and Barytherium from Africa. These animals were relatively small and aquatic. Later on, genera such as Phiomia and Palaeomastodon arose; the latter likely inhabited forests and open woodlands. Proboscidean diversity declined during the Oligocene. One notable species of this epoch was Eritreum melakeghebrekristosi of the Horn of Africa, which may have been an ancestor to several later species. The beginning of the Miocene saw the second diversification, with the appearance of the deinotheres and the mammutids. The former were related to Barytherium and lived in Africa and Eurasia, while the latter may have descended from Eritreum and spread to North America.

 

At the beginning of the Pleistocene, elephantids experienced a high rate of speciation. The Pleistocene also saw the arrival of Palaeoloxodon namadicus, the largest terrestrial mammal of all time. Loxodonta atlantica became the most common species in northern and southern Africa but was replaced by Elephas iolensis later in the Pleistocene. Only when Elephas disappeared from Africa did Loxodonta become dominant once again, this time in the form of the modern species. Elephas diversified into new species in Asia, such as E. hysudricus and E. platycephus; the latter the likely ancestor of the modern Asian elephant. Mammuthus evolved into several species, including the well-known woolly mammoth. Interbreeding appears to have been common among elephantid species, with some hybridisation which in some cases led to species with three ancestral genetic components, such as the straight-tusked elephants. In the Late Pleistocene, most proboscidean species vanished during the Quaternary glaciation which killed off 50% of genera weighing over 5 kg worldwide.

 

Proboscideans experienced several evolutionary trends, such as an increase in size, which led to many giant species that stood up to 5 m tall. As with other megaherbivores, including the extinct sauropod dinosaurs, the large size of elephants likely developed to allow them to survive on vegetation with low nutritional value. Their limbs grew longer and the feet shorter and broader. The feet were originally plantigrade and developed into a digitigrade stance with cushion pads and the sesamoid bone providing support. Early proboscideans developed longer mandibles and smaller craniums while more derived ones developed shorter mandibles, which shifted the head's centre of gravity. The skull grew larger, especially the cranium, while the neck shortened to provide better support for the skull. The increase in size led to the development and elongation of the mobile trunk to provide reach. The number of premolars, incisors and canines decreased. The cheek teeth (molars and premolars) became larger and more specialized, especially after elephants started to switch from C3-plants to C4-grasses, which caused their teeth to undergo a three-fold increase in teeth height as well as substantial multiplication of lamellae after about five million years ago. Only in the last million years or so did they return to a diet mainly consisting of C3 trees and shrubs. The upper second incisors grew into tusks, which varied in shape from straight, to curved (either upward or downward), to spiralled, depending on the species. Some proboscideans developed tusks from their lower incisors. Elephants retain certain features from their aquatic ancestry, such as their middle ear anatomy and the internal testes of the males.

 

There has been some debate over the relationship of Mammuthus to Loxodonta or Elephas. Some DNA studies suggest Mammuthus is more closely related to the former while others point to the latter. However, analysis of the complete mitochondrial genome profile of the woolly mammoth (sequenced in 2005) supports Mammuthus being more closely related to Elephas.Morphological evidence supports Mammuthus and Elephas as sister taxa while comparisons of protein albumin and collagen have concluded that all three genera are equally related to each other. Some scientists believe a cloned mammoth embryo could one day be implanted in an Asian elephant's womb.

 

DWARF SPECIES

Several species of proboscideans lived on islands and experienced insular dwarfism. This occurred primarily during the Pleistocene when some elephant populations became isolated by fluctuating sea levels, although dwarf elephants did exist earlier in the Pliocene. These elephants likely grew smaller on islands due to a lack of large or viable predator populations and limited resources. By contrast, small mammals such as rodents develop gigantism in these conditions. Dwarf proboscideans are known to have lived in Indonesia, the Channel Islands of California, and several islands of the Mediterranean.

 

Elephas celebensis of Sulawesi is believed to have descended from Elephas planifrons. Elephas falconeri of Malta and Sicily was only 1 m and had probably evolved from the straight-tusked elephant. Other descendants of the straight-tusked elephant existed in Cyprus. Dwarf elephants of uncertain descent lived in Crete, Cyclades, and Dodecanese while dwarf mammoths are known to have lived in Sardinia. The Columbian mammoth colonised the Channel Islands and evolved into the pygmy mammoth. This species reached a height of 1.2–1.8 m and weighed 200–2,000 kg. A population of small woolly mammoths survived on Wrangel Island, now 140 km north of the Siberian coast, as recently as 4,000 years ago. After their discovery in 1993, they were considered dwarf mammoths. This classification has been re-evaluated and since the Second International Mammoth Conference in 1999, these animals are no longer considered to be true "dwarf mammoths".

 

ANATOMY AND MORPHOLOGY

Elephants are the largest living terrestrial animals. On average, male African bush elephants are 3.20 m tall at the shoulder and mass/weigh 6,000 kg, whereas females are 2.60 m tall at the shoulder and mass/weigh 3,000 kg. Asian elephants are smaller, with males 2.75 m tall at the shoulder and 4,000 kg on average, and females 2.40 m tall at the shoulder and 2,700 kg on average. African forest elephants are the smallest extant species, with the average height for the species 2.00 m at the shoulder and average mass/weight 2,000 kg. Male African elephants are typically 23% taller than females, whereas male Asian elephants are only around 15% taller than females. The skeleton of the elephant is made up of 326–351 bones. The vertebrae are connected by tight joints, which limit the backbone's flexibility. African elephants have 21 pairs of ribs, while Asian elephants have 19 or 20 pairs.

 

An elephant's skull is resilient enough to withstand the forces generated by the leverage of the tusks and head-to-head collisions. The back of the skull is flattened and spread out, creating arches that protect the brain in every direction. The skull contains air cavities (sinuses) that reduce the weight of the skull while maintaining overall strength. These cavities give the inside of the skull a honeycomb-like appearance. The cranium is particularly large and provides enough room for the attachment of muscles to support the entire head. The lower jaw is solid and heavy. Because of the size of the head, the neck is relatively short to provide better support. Lacking a lacrimal apparatus, the eye relies on the harderian gland to keep it moist. A durable nictitating membrane protects the eye globe. The animal's field of vision is compromised by the location and limited mobility of the eyes. Elephants are considered dichromats and they can see well in dim light but not in bright light. The core body temperature averages 35.9 °C, similar to that of a human. Like all mammals, an elephant can raise or lower its temperature a few degrees from the average in response to extreme environmental conditions

 

EARS

Elephant ears have thick bases with thin tips. The ear flaps, or pinnae, contain numerous blood vessels called capillaries. Warm blood flows into the capillaries, helping to release excess body heat into the environment. This occurs when the pinnae are still, and the animal can enhance the effect by flapping them. Larger ear surfaces contain more capillaries, and more heat can be released. Of all the elephants, African bush elephants live in the hottest climates, and have the largest ear flaps. Elephants are capable of hearing at low frequencies and are most sensitive at 1 kHz.

 

TRUNK

The trunk, or proboscis, is a fusion of the nose and upper lip, although in early fetal life, the upper lip and trunk are separated. The trunk is elongated and specialised to become the elephant's most important and versatile appendage. It contains up to 150,000 separate muscle fascicles, with no bone and little fat. These paired muscles consist of two major types: superficial (surface) and internal. The former are divided into dorsals, ventrals, and laterals while the latter are divided into transverse and radiating muscles. The muscles of the trunk connect to a bony opening in the skull. The nasal septum is composed of tiny muscle units that stretch horizontally between the nostrils. Cartilage divides the nostrils at the base. As a muscular hydrostat, the trunk moves by precisely coordinated muscle contractions. The muscles work both with and against each other. A unique proboscis nerve – formed by the maxillary and facial nerves – runs along both sides of the trunk.

 

Elephant trunks have multiple functions, including breathing, olfaction, touching, grasping, and sound production. The animal's sense of smell may be four times as sensitive as that of a bloodhound. The trunk's ability to make powerful twisting and coiling movements allows it to collect food, wrestle with other elephants, and lift up to 350 kg). It can be used for delicate tasks, such as wiping an eye and checking an orifice, and is capable of cracking a peanut shell without breaking the seed. With its trunk, an elephant can reach items at heights of up to 7 m and dig for water under mud or sand. Individuals may show lateral preference when grasping with their trunks: some prefer to twist them to the left, others to the right. Elephants can suck up water both to drink and to spray on their bodies. An adult Asian elephant is capable of holding 8.5 L of water in its trunk. They will also spray dust or grass on themselves. When underwater, the elephant uses its trunk as a snorkel.

 

The African elephant has two finger-like extensions at the tip of the trunk that allow it to grasp and bring food to its mouth. The Asian elephant has only one, and relies more on wrapping around a food item and squeezing it into its mouth. Asian elephants have more muscle coordination and can perform more complex tasks. Losing the trunk would be detrimental to an elephant's survival, although in rare cases, individuals have survived with shortened ones. One elephant has been observed to graze by kneeling on its front legs, raising on its hind legs and taking in grass with its lips. Floppy trunk syndrome is a condition of trunk paralysis in African bush elephants caused by the degradation of the peripheral nerves and muscles beginning at the tip.

 

TEETH

Elephants usually have 26 teeth: the incisors, known as the tusks, 12 deciduous premolars, and 12 molars. Unlike most mammals, which grow baby teeth and then replace them with a single permanent set of adult teeth, elephants are polyphyodonts that have cycles of tooth rotation throughout their lives. The chewing teeth are replaced six times in a typical elephant's lifetime. Teeth are not replaced by new ones emerging from the jaws vertically as in most mammals. Instead, new teeth grow in at the back of the mouth and move forward to push out the old ones. The first chewing tooth on each side of the jaw falls out when the elephant is two to three years old. The second set of chewing teeth falls out at four to six years old. The third set falls out at 9–15 years of age, and set four lasts until 18–28 years of age. The fifth set of teeth falls out at the early 40s. The sixth (and usually final) set must last the elephant the rest of its life. Elephant teeth have loop-shaped dental ridges, which are thicker and more diamond-shaped in African elephants.

 

TUSKS

The tusks of an elephant are modified second incisors in the upper jaw. They replace deciduous milk teeth at 6–12 months of age and grow continuously at about 17 cm a year. A newly developed tusk has a smooth enamel cap that eventually wears off. The dentine is known as ivory and its cross-section consists of crisscrossing line patterns, known as "engine turning", which create diamond-shaped areas. As a piece of living tissue, a tusk is relatively soft; it is as hard as the mineral calcite. Much of the tusk can be seen outside; the rest is in a socket in the skull. At least one-third of the tusk contains the pulp and some have nerves stretching to the tip. Thus it would be difficult to remove it without harming the animal. When removed, ivory begins to dry up and crack if not kept cool and moist. Tusks serve multiple purposes. They are used for digging for water, salt, and roots; debarking or marking trees; and for moving trees and branches when clearing a path. When fighting, they are used to attack and defend, and to protect the trunk.

 

Like humans, who are typically right- or left-handed, elephants are usually right- or left-tusked. The dominant tusk, called the master tusk, is generally more worn down, as it is shorter with a rounder tip. For the African elephants, tusks are present in both males and females, and are around the same length in both sexes, reaching up to 3 m, but those of males tend to be thicker. In earlier times, elephant tusks weighing more than 90 kg were not uncommon, though it is rare today to see any over 45 kg.

 

In the Asian species, only the males have large tusks. Female Asians have very small tusks, or none at all. Tuskless males exist and are particularly common among Sri Lankan elephants. Asian males can have tusks as long as Africans', but they are usually slimmer and lighter; the largest recorded was 3.02 m long and weighed 39 kg. Hunting for elephant ivory in Africa and Asia has led to natural selection for shorter tusks and tusklessness.

 

SKIN

An elephant's skin is generally very tough, at 2.5 cm thick on the back and parts of the head. The skin around the mouth, anus, and inside of the ear is considerably thinner. Elephants typically have grey skin, but African elephants look brown or reddish after wallowing in coloured mud. Asian elephants have some patches of depigmentation, particularly on the forehead and ears and the areas around them. Calves have brownish or reddish hair, especially on the head and back. As elephants mature, their hair darkens and becomes sparser, but dense concentrations of hair and bristles remain on the end of the tail as well as the chin, genitals and the areas around the eyes and ear openings. Normally the skin of an Asian elephant is covered with more hair than its African counterpart.An elephant uses mud as a sunscreen, protecting its skin from ultraviolet light. Although tough, an elephant's skin is very sensitive. Without regular mud baths to protect it from burning, insect bites and moisture loss, an elephant's skin suffers serious damage. After bathing, the elephant will usually use its trunk to blow dust onto its body and this dries into a protective crust. Elephants have difficulty releasing heat through the skin because of their low surface-area-to-volume ratio, which is many times smaller than that of a human. They have even been observed lifting up their legs, presumably in an effort to expose their soles to the air.

 

LEGS, LOCOMOTION AND POSTURE

To support the animal's weight, an elephant's limbs are positioned more vertically under the body than in most other mammals. The long bones of the limbs have cancellous bone in place of medullary cavities. This strengthens the bones while still allowing haematopoiesis. Both the front and hind limbs can support an elephant's weight, although 60% is borne by the front. Since the limb bones are placed on top of each other and under the body, an elephant can stand still for long periods of time without using much energy. Elephants are incapable of rotating their front legs, as the ulna and radius are fixed in pronation; the "palm" of the manus faces backward. The pronator quadratus and the pronator teres are either reduced or absent. The circular feet of an elephant have soft tissues or "cushion pads" beneath the manus or pes, which distribute the weight of the animal. They appear to have a sesamoid, an extra "toe" similar in placement to a giant panda's extra "thumb", that also helps in weight distribution. As many as five toenails can be found on both the front and hind feet.

 

Elephants can move both forwards and backwards, but cannot trot, jump, or gallop. They use only two gaits when moving on land: the walk and a faster gait similar to running. In walking, the legs act as pendulums, with the hips and shoulders rising and falling while the foot is planted on the ground. With no "aerial phase", the fast gait does not meet all the criteria of running, although the elephant uses its legs much like other running animals, with the hips and shoulders falling and then rising while the feet are on the ground. Fast-moving elephants appear to 'run' with their front legs, but 'walk' with their hind legs and can reach a top speed of 25 km/h. At this speed, most other quadrupeds are well into a gallop, even accounting for leg length. Spring-like kinetics could explain the difference between the motion of elephants and other animals. During locomotion, the cushion pads expand and contract, and reduce both the pain and noise that would come from a very heavy animal moving. Elephants are capable swimmers. They have been recorded swimming for up to six hours without touching the bottom, and have travelled as far as 48 km at a stretch and at speeds of up to 2.1 km/h.

 

INTERNAL AND SEXUAL ORGANS

The brain of an elephant weighs 4.5–5.5 kg compared to 1.6 kg for a human brain. While the elephant brain is larger overall, it is proportionally smaller. At birth, an elephant's brain already weighs 30–40% of its adult weight. The cerebrum and cerebellum are well developed, and the temporal lobes are so large that they bulge out laterally. The throat of an elephant appears to contain a pouch where it can store water for later use.

 

The heart of an elephant weighs 12–21 kg. It has a double-pointed apex, an unusual trait among mammals. In addition, the ventricles separate near the top of the heart, a trait they share with sirenians. When standing, the elephant's heart beats approximately 30 times per minute. Unlike many other animals, the heart rate speeds up by 8 to 10 beats per minute when the elephant is lying down. The blood vessels in most of the body are wide and thick and can withstand high blood pressures. The lungs are attached to the diaphragm, and breathing relies mainly on the diaphragm rather than the expansion of the ribcage. Connective tissue exists in place of the pleural cavity. This may allow the animal to deal with the pressure differences when its body is underwater and its trunk is breaking the surface for air, although this explanation has been questioned. Another possible function for this adaptation is that it helps the animal suck up water through the trunk. Elephants inhale mostly through the trunk, although some air goes through the mouth. They have a hindgut fermentation system, and their large and small intestines together reach 35 m in length. The majority of an elephant's food intake goes undigested despite the process lasting up to a day.

 

A male elephant's testes are located internally near the kidneys. The elephant's penis can reach a length of 100 cm and a diameter of 16 cm at the base. It is S-shaped when fully erect and has a Y-shaped orifice. The female has a well-developed clitoris at up to 40 cm. The vulva is located between the hind legs instead of near the tail as in most mammals. Determining pregnancy status can be difficult due to the animal's large abdominal cavity. The female's mammary glands occupy the space between the front legs, which puts the suckling calf within reach of the female's trunk. Elephants have a unique organ, the temporal gland, located in both sides of the head. This organ is associated with sexual behaviour, and males secrete a fluid from it when in musth. Females have also been observed with secretions from the temporal glands.

 

BEHAVIOUR AND LIFE HISTORY

ECOLOGY AND ACTIVITIES

The African bush elephant can be found in habitats as diverse as dry savannahs, deserts, marshes, and lake shores, and in elevations from sea level to mountain areas above the snow line. Forest elephants mainly live in equatorial forests but will enter gallery forests and ecotones between forests and savannahs. Asian elephants prefer areas with a mix of grasses, low woody plants, and trees, primarily inhabiting dry thorn-scrub forests in southern India and Sri Lanka and evergreen forests in Malaya. Elephants are herbivorous and will eat leaves, twigs, fruit, bark, grass and roots. They are born with sterile intestines and require bacteria obtained from their mother's feces to digest vegetation. African elephants are mostly browsers while Asian elephants are mainly grazers. They can consume as much as 150 kg of food and 40 L (11 US gal) of water in a day. Elephants tend to stay near water sources. Major feeding bouts take place in the morning, afternoon and night. At midday, elephants rest under trees and may doze off while standing. Sleeping occurs at night while the animal is lying down. Elephants average 3–4 hours of sleep per day. Both males and family groups typically move 10–20 km a day, but distances as far as 90–180 km have been recorded in the Etosha region of Namibia. Elephants go on seasonal migrations in search of food, water, minerals, and mates. At Chobe National Park, Botswana, herds travel 325 km to visit the river when the local waterholes dry up.

 

Because of their large size, elephants have a huge impact on their environments and are considered keystone species. Their habit of uprooting trees and undergrowth can transform savannah into grasslands; when they dig for water during drought, they create waterholes that can be used by other animals. They can enlarge waterholes when they bathe and wallow in them. At Mount Elgon, elephants excavate caves that are used by ungulates, hyraxes, bats, birds and insects. Elephants are important seed dispersers; African forest elephants ingest and defecate seeds, with either no effect or a positive effect on germination. The seeds are typically dispersed in large amounts over great distances. In Asian forests, large seeds require giant herbivores like elephants and rhinoceros for transport and dispersal. This ecological niche cannot be filled by the next largest herbivore, the tapir. Because most of the food elephants eat goes undigested, their dung can provide food for other animals, such as dung beetles and monkeys. Elephants can have a negative impact on ecosystems. At Murchison Falls National Park in Uganda, the overabundance of elephants has threatened several species of small birds that depend on woodlands. Their weight can compact the soil, which causes the rain to run off, leading to erosion.

 

Elephants typically coexist peacefully with other herbivores, which will usually stay out of their way. Some aggressive interactions between elephants and rhinoceros have been recorded. At Aberdare National Park, Kenya, a rhino attacked an elephant calf and was killed by the other elephants in the group. At Hluhluwe-Umfolozi Game Reserve, South Africa, introduced young orphan elephants went on a killing spree that claimed the lives of 36 rhinos during the 1990s, but ended with the introduction of older males. The size of adult elephants makes them nearly invulnerable to predators, though there are rare reports of adult elephants falling prey to tigers. Calves may be preyed on by lions, spotted hyenas, and wild dogs in Africa and tigers in Asia. The lions of Savuti, Botswana, have adapted to hunting juvenile elephants during the dry season, and a pride of 30 lions has been recorded killing juvenile individuals between the ages of four and eleven years. Elephants appear to distinguish between the growls of larger predators like tigers and smaller predators like leopards (which have not been recorded killing calves); they react to leopards less fearfully and more aggressively. Elephants tend to have high numbers of parasites, particularly nematodes, compared to other herbivores. This is due to lower predation pressures that would otherwise kill off many of the individuals with significant parasite loads.

 

SOCIAL ORGANISATION

Female elephants spend their entire lives in tight-knit matrilineal family groups, some of which are made up of more than ten members, including three pairs of mothers with offspring, and are led by the matriarch which is often the eldest female. She remains leader of the group until death or if she no longer has the energy for the role; a study on zoo elephants showed that when the matriarch died, the levels of faecal corticosterone ('stress hormone') dramatically increased in the surviving elephants. When her tenure is over, the matriarch's eldest daughter takes her place; this occurs even if her sister is present. The older matriarchs tend to be more effective decision-makers.

 

The social circle of the female elephant does not necessarily end with the small family unit. In the case of elephants in Amboseli National Park, Kenya, a female's life involves interaction with other families, clans, and subpopulations. Families may associate and bond with each other, forming what are known as bond groups. These are typically made of two family groups, which may be closely related due to previously being part of the same family group which split after becoming too large for the available resources. During the dry season, elephant families may cluster together and form another level of social organisation known as the clan. Groups within these clans do not form strong bonds, but they defend their dry-season ranges against other clans. There are typically nine groups in a clan. The Amboseli elephant population is further divided into the "central" and "peripheral" subpopulations.

 

Some elephant populations in India and Sri Lanka have similar basic social organisations. There appear to be cohesive family units and loose aggregations. They have been observed to have "nursing units" and "juvenile-care units". In southern India, elephant populations may contain family groups, bond groups and possibly clans. Family groups tend to be small, consisting of one or two adult females and their offspring. A group containing more than two adult females plus offspring is known as a "joint family". Malay elephant populations have even smaller family units, and do not have any social organisation higher than a family or bond group. Groups of African forest elephants typically consist of one adult female with one to three offspring. These groups appear to interact with each other, especially at forest clearings.

The social life of the adult male is very different. As he matures, a male spends more time at the edge of his group and associates with outside males or even other families. At Amboseli, young males spend over 80% of their time away from their families when they are 14–15. When males permanently leave, they either live alone or with other males. The former is typical of bulls in dense forests. Asian males are usually solitary, but occasionally form groups of two or more individuals; the largest consisted of seven bulls. Larger bull groups consisting of over 10 members occur only among African bush elephants, the largest of which numbered up to 144 individuals. These elephants can be quite sociable when not competing for dominance or mates, and will form long-term relationships. A dominance hierarchy exists among males, whether they range socially or solitarily. Dominance depends on the age, size and sexual condition, and when in groups, males follow the lead of the dominant bull. Young bulls may seek out the company and leadership of older, more experienced males, whose presence appears to control their aggression and prevent them from exhibiting "deviant" behaviour. Adult males and females come together for reproduction. Bulls associate with family groups if an oestrous cow is present.

 

SEXUAL BEHAVIOUR

MUSTH

Adult males enter a state of increased testosterone known as musth. In a population in southern India, males first enter musth at the age of 15, but it is not very intense until they are older than 25. At Amboseli, bulls under 24 do not go into musth, while half of those aged 25–35 and all those over 35 do. Young bulls appear to enter musth during the dry season (January–May), while older bulls go through it during the wet season (June–December). The main characteristic of a bull's musth is a fluid secreted from the temporal gland that runs down the side of his face. He may urinate with his penis still in his sheath, which causes the urine to spray on his hind legs. Behaviours associated with musth include walking with the head held high and swinging, picking at the ground with the tusks, marking, rumbling and waving only one ear at a time. This can last from a day to four months.

 

Males become extremely aggressive during musth. Size is the determining factor in agonistic encounters when the individuals have the same condition. In contests between musth and non-musth individuals, musth bulls win the majority of the time, even when the non-musth bull is larger. A male may stop showing signs of musth when he encounters a musth male of higher rank. Those of equal rank tend to avoid each other. Agonistic encounters typically consist of threat displays, chases, and minor sparring with the tusks. Serious fights are rare.

 

MATING

Elephants are polygynous breeders, and copulations are most frequent during the peak of the wet season. A cow in oestrus releases chemical signals (pheromones) in her urine and vaginal secretions to signal her readiness to mate. A bull will follow a potential mate and assess her condition with the flehmen response, which requires the male to collect a chemical sample with his trunk and bring it to the vomeronasal organ. The oestrous cycle of a cow lasts 14–16 weeks with a 4–6-week follicular phase and an 8- to 10-week luteal phase. While most mammals have one surge of luteinizing hormone during the follicular phase, elephants have two. The first (or anovulatory) surge, could signal to males that the female is in oestrus by changing her scent, but ovulation does not occur until the second (or ovulatory) surge. Fertility rates in cows decline around 45–50 years of age.

_____________________________

. . . for Part 2 go to: Elephants - 2

 

WIKIPEDIA

Those two lower incisors were pulled back in 2014 because they couldn't be saved:(

Now we just have to say that he is definitely MR. PERSONALITY!

Phnom Penh

Cambodia

21 Oct 2013

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This article is about a paraphyletic group. For close extinct relatives, see Elephantidae. For other uses, see Elephant (disambiguation).

Elephants

Temporal range: Pliocene–Present

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From top left to right: the African bush elephant, the Asian elephant and African forest elephant.

From top left to right: the African bush elephant, the Asian elephant and African forest elephant.

Scientific classificationEdit this classification

Kingdom:Animalia

Phylum:Chordata

Class:Mammalia

Order:Proboscidea

Family:Elephantidae

Subfamily:Elephantinae

Groups included

Loxodonta Anonymous, 1827

Elephas Linnaeus, 1758

†Palaeoloxodon Matsumoto, 1925

Cladistically included but traditionally excluded taxa

†Mammuthus Brookes, 1828

†Primelephas Maglio, 1970

Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are an informal grouping within the proboscidean family Elephantidae. Elephantidae is the only surviving family of proboscideans; extinct members include the mastodons. Elephantidae also contains several extinct groups, including the mammoths and straight-tusked elephants. African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears, and convex or level backs. Distinctive features of all elephants include a long proboscis called a trunk, tusks, large ear flaps, massive legs, and tough but sensitive skin. The trunk is used for breathing, bringing food and water to the mouth, and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. The pillar-like legs carry their great weight.

 

Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia and are found in different habitats, including savannahs, forests, deserts, and marshes. They are herbivorous, and they stay near water when it is accessible. They are considered to be keystone species, due to their impact on their environments. Elephants have a fission–fusion society, in which multiple family groups come together to socialise. Females (cows) tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups, which do not include bulls, are usually led by the oldest cow, known as the matriarch.

 

Males (bulls) leave their family groups when they reach puberty and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate. They enter a state of increased testosterone and aggression known as musth, which helps them gain dominance over other males as well as reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell, and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness, and appear to show empathy for dying and dead family members.

 

African bush elephants and Asian elephants are listed as endangered and African forest elephants as critically endangered by the International Union for Conservation of Nature (IUCN). One of the biggest threats to elephant populations is the ivory trade, as the animals are poached for their ivory tusks. Other threats to wild elephants include habitat destruction and conflicts with local people. Elephants are used as working animals in Asia. In the past, they were used in war; today, they are often controversially put on display in zoos, or exploited for entertainment in circuses. Elephants are highly recognisable and have been featured in art, folklore, religion, literature, and popular culture.

Etymology

The word "elephant" is based on the Latin elephas (genitive elephantis) ("elephant"), which is the Latinised form of the Greek ἐλέφας (elephas) (genitive ἐλέφαντος (elephantos[1]), probably from a non-Indo-European language, likely Phoenician.[2] It is attested in Mycenaean Greek as e-re-pa (genitive e-re-pa-to) in Linear B syllabic script.[3][4] As in Mycenaean Greek, Homer used the Greek word to mean ivory, but after the time of Herodotus, it also referred to the animal.[1] The word "elephant" appears in Middle English as olyfaunt (c.1300) and was borrowed from Old French oliphant (12th century).[2]

 

Taxonomy and phylogeny

Afrotheria

Afroinsectiphilia

Tubulidentata

Orycteropodidae Aardvark2 (PSF) colourised.png

  

Afroinsectivora

Macroscelidea

Macroscelididae Rhynchocyon chrysopygus-J Smit white background.jpg

  

Afrosoricida

 

Chrysochloridae The animal kingdom, arranged according to its organization, serving as a foundation for the natural history of animals (Pl. 18) (Chrysochloris asiatica).jpg

   

Tenrecidae Brehms Thierleben - Allgemeine Kunde des Thierreichs (1876) (Tenrec ecaudatus).jpg

     

Paenungulata

Hyracoidea

Procaviidae DendrohyraxEminiSmit white background.jpg

  

Tethytheria

Proboscidea

Elephantidae Elephas africanus - 1700-1880 - Print - Iconographia Zoologica - (white background).jpg

  

Sirenia

 

Dugongidae Dugong dugon Hardwicke white background.jpg

   

Trichechidae Manatee white background.jpg

      

A cladogram of the elephants within Afrotheria based on molecular evidence[5]

Proboscidea

 

early proboscideans, e.g. Moeritherium Moeritherium NT small.jpg

    

Deinotheriidae Deinotherium12.jpg

  

Elephantiformes

 

Mammutidae BlankMastodon.jpg

    

Gomphotheriidae Gomphotherium NT small.jpg

    

Stegodontidae Stegodon Siwalik Hills.jpg

  

Elephantidae

 

Loxodonta African Bush Elephant.jpg

    

Mammuthus Mammuthus trogontherii122DB.jpg

   

Elephas Elephas maximus (Bandipur).jpg

         

Proboscidea phylogeny based on upper molars.[6]

Elephantimorpha

Elephantidae

   

Mammuthus primigenius Woolly mammoth model Royal BC Museum in Victoria.jpg

   

Mammuthus columbi Archidiskodon imperator121.jpg

    

Elephas maximus Elephas maximus (Bandipur).jpg

      

Loxodonta cyclotis African Forest Elephant.jpg

   

Palaeoloxodon antiquus Elephas-antiquus.jpg

    

Loxodonta africana African Bush Elephant.jpg

     

Mammut americanum BlankMastodon.jpg

   

Phylogeny of modern elephants and close extinct relatives based on molecular evidence[7]

See also: List of elephant species

Elephants belong to the family Elephantidae, the sole remaining family within the order Proboscidea which belongs to the superorder Afrotheria. Their closest extant relatives are the sirenians (dugongs and manatees) and the hyraxes, with which they share the clade Paenungulata within the superorder Afrotheria.[8] Elephants and sirenians are further grouped in the clade Tethytheria.[9]

 

Three species of elephants are recognised; the African bush elephant (Loxodonta africana) and forest elephant (Loxodonta cyclotis) of sub-Saharan Africa, and the Asian elephant (Elephas maximus) of South and Southeast Asia.[10] African elephants have larger ears, a concave back, more wrinkled skin, a sloping abdomen, and two finger-like extensions at the tip of the trunk. Asian elephants have smaller ears, a convex or level back, smoother skin, a horizontal abdomen that occasionally sags in the middle and one extension at the tip of the trunk. The looped ridges on the molars are narrower in the Asian elephant while those of the African are more diamond-shaped. The Asian elephant also has dorsal bumps on its head and some patches of depigmentation on its skin.[11]

 

Among African elephants, forest elephants have smaller and more rounded ears and thinner and straighter tusks than bush elephants and are limited in range to the forested areas of western and Central Africa.[12] Both were traditionally considered a single species, Loxodonta africana, but molecular studies have affirmed their status as separate species.[13][14][15] In 2017, DNA sequence analysis showed that L. cyclotis is more closely related to the extinct Palaeoloxodon antiquus, than it is to L. africana, possibly undermining the genus Loxodonta as a whole.[16]

 

Evolution and extinct relatives

Over 180 extinct members and three major evolutionary radiations of the order Proboscidea have been recorded.[17] The earliest proboscids, the African Eritherium and Phosphatherium of the late Paleocene, heralded the first radiation.[18] The Eocene included Numidotherium, Moeritherium, and Barytherium from Africa. These animals were relatively small and aquatic. Later on, genera such as Phiomia and Palaeomastodon arose; the latter likely inhabited forests and open woodlands. Proboscidean diversity declined during the Oligocene.[19] One notable species of this epoch was Eritreum melakeghebrekristosi of the Horn of Africa, which may have been an ancestor to several later species.[20] The beginning of the Miocene saw the second diversification, with the appearance of the deinotheres and the mammutids. The former were related to Barytherium and lived in Africa and Eurasia,[21] while the latter may have descended from Eritreum[20] and spread to North America.[21]

 

The second radiation was represented by the emergence of the gomphotheres in the Miocene,[21] which likely evolved from Eritreum[20] and originated in Africa, spreading to every continent except Australia and Antarctica. Members of this group included Gomphotherium and Platybelodon.[21] The third radiation started in the late Miocene and led to the arrival of the elephantids, which descended from, and slowly replaced, the gomphotheres.[22] The African Primelephas gomphotheroides gave rise to Loxodonta, Mammuthus, and Elephas. Loxodonta branched off earliest around the Miocene and Pliocene boundary while Mammuthus and Elephas diverged later during the early Pliocene. Loxodonta remained in Africa while Mammuthus and Elephas spread to Eurasia, and the former reached North America. At the same time, the stegodontids, another proboscidean group descended from gomphotheres, spread throughout Asia, including the Indian subcontinent, China, southeast Asia, and Japan. Mammutids continued to evolve into new species, such as the American mastodon.[23]

 

At the beginning of the Pleistocene, elephantids experienced a high rate of speciation.[24] The Pleistocene also saw the arrival of Palaeoloxodon namadicus, the largest terrestrial mammal of all time.[25] Loxodonta atlantica became the most common species in northern and southern Africa but was replaced by Elephas iolensis later in the Pleistocene. Only when Elephas disappeared from Africa did Loxodonta become dominant once again, this time in the form of the modern species. Elephas diversified into new species in Asia, such as E. hysudricus and E. platycephus;[26] the latter the likely ancestor of the modern Asian elephant.[24] Mammuthus evolved into several species, including the well-known woolly mammoth.[26] Interbreeding appears to have been common among elephantid species, which in some cases led to species with three ancestral genetic components, such as the Palaeoloxodon antiquus.[7] In the Late Pleistocene, most proboscidean species vanished during the Quaternary glaciation which killed off 50% of genera weighing over 5 kg (11 lb) worldwide.[27]

 

Proboscideans experienced several evolutionary trends, such as an increase in size, which led to many giant species that stood up to 500 cm (16 ft 5 in) tall.[25] As with other megaherbivores, including the extinct sauropod dinosaurs, the large size of elephants likely developed to allow them to survive on vegetation with low nutritional value.[28] Their limbs grew longer and the feet shorter and broader.[6] The feet were originally plantigrade and developed into a digitigrade stance with cushion pads and the sesamoid bone providing support.[29] Early proboscideans developed longer mandibles and smaller craniums while more derived ones developed shorter mandibles, which shifted the head's centre of gravity. The skull grew larger, especially the cranium, while the neck shortened to provide better support for the skull. The increase in size led to the development and elongation of the mobile trunk to provide reach. The number of premolars, incisors and canines decreased.[6]

 

The cheek teeth (molars and premolars) of proboscideans became larger and more specialized, especially after elephants started to switch from C3-plants to C4-grasses, which caused their teeth to undergo a three-fold increase in teeth height as well as substantial multiplication of lamellae after about five million years ago. Only in the last million years or so did they return to a diet mainly consisting of C3 trees and shrubs.[30][31] The upper second incisors grew into tusks, which varied in shape from straight, to curved (either upward or downward), to spiralled, depending on the species. Some proboscideans developed tusks from their lower incisors.[6] Elephants retain certain features from their aquatic ancestry, such as their middle ear anatomy.[32]

 

Several species of proboscideans lived on islands and experienced insular dwarfism. This occurred primarily during the Pleistocene when some elephant populations became isolated by fluctuating sea levels, although dwarf elephants did exist earlier in the Pliocene. These elephants likely grew smaller on islands due to a lack of large or viable predator populations and limited resources. By contrast, small mammals such as rodents develop gigantism in these conditions. Dwarf elephants are known to have lived in Indonesia, the Channel Islands of California, and several islands of the Mediterranean.[33]

Anatomy and morphology

Size

 

African bush elephant skeleton

Elephants are the largest living terrestrial animals. African bush elephants are the largest species, with males being 304–336 cm (10 ft 0 in–11 ft 0 in) tall at the shoulder with a body mass of 5.2–6.9 t (5.7–7.6 short tons) and females standing 247–273 cm (8 ft 1 in–8 ft 11 in) tall at the shoulder with a body mass of 2.6–3.5 t (2.9–3.9 short tons). Male Asian elephants are usually about 261–289 cm (8 ft 7 in–9 ft 6 in) tall at the shoulder and 3.5–4.6 t (3.9–5.1 short tons) whereas females are 228–252 cm (7 ft 6 in–8 ft 3 in) tall at the shoulder and 2.3–3.1 t (2.5–3.4 short tons). African forest elephants are the smallest species, with males usually being around 209–231 cm (6 ft 10 in–7 ft 7 in) tall at the shoulder and 1.7–2.3 t (1.9–2.5 short tons). Male African bush elephants are typically 23% taller than females, whereas male Asian elephants are only around 15% taller than females.[25]

 

Bones

The skeleton of the elephant is made up of 326–351 bones.[34] The vertebrae are connected by tight joints, which limit the backbone's flexibility. African elephants have 21 pairs of ribs, while Asian elephants have 19 or 20 pairs.[35]

 

Head

An elephant's skull is resilient enough to withstand the forces generated by the leverage of the tusks and head-to-head collisions. The back of the skull is flattened and spread out, creating arches that protect the brain in every direction.[36] The skull contains air cavities (sinuses) that reduce the weight of the skull while maintaining overall strength. These cavities give the inside of the skull a honeycomb-like appearance. The cranium is particularly large and provides enough room for the attachment of muscles to support the entire head. The lower jaw is solid and heavy.[34] Because of the size of the head, the neck is relatively short to provide better support.[6] Lacking a lacrimal apparatus, the eye relies on the harderian gland to keep it moist. A durable nictitating membrane protects the eye globe. The animal's field of vision is compromised by the location and limited mobility of the eyes.[37] Elephants are considered dichromats[38] and they can see well in dim light but not in bright light.[39]

  

African bush elephant with ears spread in a threat or attentive position; note the visible blood vessels

Ears

Elephant ears have thick bases with thin tips. The ear flaps, or pinnae, contain numerous blood vessels called capillaries. Warm blood flows into the capillaries, helping to release excess body heat into the environment. This occurs when the pinnae are still, and the animal can enhance the effect by flapping them. Larger ear surfaces contain more capillaries, and more heat can be released. Of all the elephants, African bush elephants live in the hottest climates, and have the largest ear flaps.[40] Elephants are capable of hearing at low frequencies and are most sensitive at 1 kHz (in close proximity to the Soprano C).[41]

 

Trunk

 

African bush elephant with its trunk raised, a behaviour often adopted when trumpeting

 

Asian elephant drinking water with trunk

The trunk, or proboscis, is a fusion of the nose and upper lip, although in early fetal life, the upper lip and trunk are separated.[6] The trunk is elongated and specialised to become the elephant's most important and versatile appendage. It contains up to 150,000 separate muscle fascicles,[42] with no bone and little fat. These paired muscles consist of two major types: superficial (surface) and internal. The former are divided into dorsals, ventrals, and laterals while the latter are divided into transverse and radiating muscles. The muscles of the trunk connect to a bony opening in the skull. The nasal septum is composed of tiny muscle units that stretch horizontally between the nostrils. Cartilage divides the nostrils at the base.[43] As a muscular hydrostat, the trunk moves by precisely coordinated muscle contractions. The muscles work both with and against each other. A unique proboscis nerve – formed by the maxillary and facial nerves – runs along both sides of the trunk.[44]

 

Elephant trunks have multiple functions, including breathing, olfaction, touching, grasping, and sound production.[6] The animal's sense of smell may be four times as sensitive as that of a bloodhound.[45] The trunk's ability to make powerful twisting and coiling movements allows it to collect food, wrestle with other elephants,[46] and lift up to 350 kg (770 lb).[6] It can be used for delicate tasks, such as wiping an eye and checking an orifice,[46] and is capable of cracking a peanut shell without breaking the seed.[6] With its trunk, an elephant can reach items at heights of up to 7 m (23 ft) and dig for water under mud or sand.[46] Individuals may show lateral preference when grasping with their trunks: some prefer to twist them to the left, others to the right.[44] Elephants are capable of dilating their nostrils at a radius of nearly 30%, increasing the nasal volume by 64%, and can inhale at over 150 m/s (490 ft/s) which is around 30 times the speed of a human sneeze.[47] Elephants can suck up food and water both to spray in the mouth and, in the case of the later, to sprinkle on their bodies.[6][47] An adult Asian elephant is capable of holding 8.5 L (2.2 US gal) of water in its trunk.[43] They will also spray dust or grass on themselves.[6] When underwater, the elephant uses its trunk as a snorkel.[32]

 

The African elephant has two finger-like extensions at the tip of the trunk that allow it to grasp and bring food to its mouth. The Asian elephant has only one and relies more on wrapping around a food item and squeezing it into its mouth.[11] Asian elephants have more muscle coordination and can perform more complex tasks.[43] Losing the trunk would be detrimental to an elephant's survival,[6] although in rare cases, individuals have survived with shortened ones. One elephant has been observed to graze by kneeling on its front legs, raising on its hind legs and taking in grass with its lips.[43] Floppy trunk syndrome is a condition of trunk paralysis in African bush elephants caused by the degradation of the peripheral nerves and muscles beginning at the tip.[48]

 

Teeth

 

Closeup of the cheek teeth of a dead juvenile bush elephant

 

Asian elephant eating tree bark, using its tusks to peel it off.

Elephants usually have 26 teeth: the incisors, known as the tusks, 12 deciduous premolars, and 12 molars. Unlike most mammals, which grow baby teeth and then replace them with a single permanent set of adult teeth, elephants are polyphyodonts that have cycles of tooth rotation throughout their lives. The chewing teeth are replaced six times in a typical elephant's lifetime. Teeth are not replaced by new ones emerging from the jaws vertically as in most mammals. Instead, new teeth grow in at the back of the mouth and move forward to push out the old ones. The first chewing tooth on each side of the jaw falls out when the elephant is two to three years old. The second set of chewing teeth falls out at four to six years old. The third set falls out at 9–15 years of age and set four lasts until 18–28 years of age. The fifth set of teeth falls out at the early 40s. The sixth (and usually final) set must last the elephant the rest of its life. Elephant teeth have loop-shaped dental ridges, which are thicker and more diamond-shaped in African elephants.[49]

 

Tusks

The tusks of an elephant are modified second incisors in the upper jaw. They replace deciduous milk teeth at 6–12 months of age and grow continuously at about 17 cm (7 in) a year. A newly developed tusk has a smooth enamel cap that eventually wears off. The dentine is known as ivory and its cross-section consists of crisscrossing line patterns, known as "engine turning", which create diamond-shaped areas. As a piece of living tissue, a tusk is relatively soft; it is as hard as the mineral calcite. Much of the tusk can be seen outside; the rest is in a socket in the skull. At least one-third of the tusk contains the pulp and some have nerves stretching to the tip. Thus it would be difficult to remove it without harming the animal. When removed, ivory begins to dry up and crack if not kept cool and moist. Tusks serve multiple purposes. They are used for digging for water, salt, and roots; debarking or marking trees; and for moving trees and branches when clearing a path. When fighting, they are used to attack and defend, and to protect the trunk.[50]

 

Like humans, who are typically right- or left-handed, elephants are usually right- or left-tusked. The dominant tusk, called the master tusk, is generally more worn down, as it is shorter with a rounder tip. For the African elephants, tusks are present in both males and females, and are around the same length in both sexes, reaching up to 300 cm (9 ft 10 in),[50] but those of males tend to be thicker.[51] In earlier times, elephant tusks weighing over 200 pounds (more than 90 kg) were not uncommon, though it is rare today to see any over 100 pounds (45 kg).[52]

 

In the Asian species, only the males have large tusks. Female Asians have very small tusks, or none at all.[50] Tuskless males exist and are particularly common among Sri Lankan elephants.[53] Asian males can have tusks as long as Africans', but they are usually slimmer and lighter; the largest recorded was 302 cm (9 ft 11 in) long and weighed 39 kg (86 lb). Hunting for elephant ivory in Africa[54] and Asia[55] has led to natural selection for shorter tusks[56][57] and tusklessness.[58][59]

 

Skin

 

An African forest elephant covering its skin with mud

An elephant's skin is generally very tough, at 2.5 cm (1 in) thick on the back and parts of the head. The skin around the mouth, anus, and inside of the ear is considerably thinner. Elephants typically have grey skin, but African elephants look brown or reddish after wallowing in coloured mud. Asian elephants have some patches of depigmentation, particularly on the forehead and ears and the areas around them. Calves have brownish or reddish hair, especially on the head and back. As elephants mature, their hair darkens and becomes sparser, but dense concentrations of hair and bristles remain on the end of the tail as well as the chin, genitals and the areas around the eyes and ear openings. Normally the skin of an Asian elephant is covered with more hair than its African counterpart.[60] Their hair is thought to be for thermoregulation, helping them lose heat in their hot environments.[61]

 

An elephant uses mud as a sunscreen, protecting its skin from ultraviolet light. Although tough, an elephant's skin is very sensitive. Without regular mud baths to protect it from burning, insect bites and moisture loss, an elephant's skin suffers serious damage. After bathing, the elephant will usually use its trunk to blow dust onto its body and this dries into a protective crust. Elephants have difficulty releasing heat through the skin because of their low surface-area-to-volume ratio, which is many times smaller than that of a human. They have even been observed lifting up their legs, presumably in an effort to expose their soles to the air.[60]

 

Legs, locomotion, and posture

 

An Asian elephant walking

To support the animal's weight, an elephant's limbs are positioned more vertically under the body than in most other mammals. The long bones of the limbs have cancellous bone in place of medullary cavities. This strengthens the bones while still allowing haematopoiesis.[62] Both the front and hind limbs can support an elephant's weight, although 60% is borne by the front.[63] Since the limb bones are placed on top of each other and under the body, an elephant can stand still for long periods of time without using much energy. Elephants are incapable of rotating their front legs, as the ulna and radius are fixed in pronation; the "palm" of the manus faces backward.[62] The pronator quadratus and the pronator teres are either reduced or absent.[64] The circular feet of an elephant have soft tissues or "cushion pads" beneath the manus or pes, which distribute the weight of the animal.[63] They appear to have a sesamoid, an extra "toe" similar in placement to a giant panda's extra "thumb", that also helps in weight distribution.[65] As many as five toenails can be found on both the front and hind feet.[11]

 

Elephants can move both forwards and backwards, but cannot trot, jump, or gallop. They use only two gaits when moving on land: the walk and a faster gait similar to running.[62] In walking, the legs act as pendulums, with the hips and shoulders rising and falling while the foot is planted on the ground. With no "aerial phase", the fast gait does not meet all the criteria of running, although the elephant uses its legs much like other running animals, with the hips and shoulders falling and then rising while the feet are on the ground.[66] Fast-moving elephants appear to 'run' with their front legs, but 'walk' with their hind legs and can reach a top speed of 25 km/h (16 mph).[67] At this speed, most other quadrupeds are well into a gallop, even accounting for leg length. Spring-like kinetics could explain the difference between the motion of elephants and other animals.[67] During locomotion, the cushion pads expand and contract, and reduce both the pain and noise that would come from a very heavy animal moving.[63] Elephants are capable swimmers. They have been recorded swimming for up to six hours without touching the bottom, and have travelled as far as 48 km (30 mi) at a stretch and at speeds of up to 2.1 km/h (1 mph).[68]

 

Organs

 

African elephant heart in a jar

The brain of an elephant weighs 4.5–5.5 kg (10–12 lb) compared to 1.6 kg (4 lb) for a human brain. While the elephant brain is larger overall, it is proportionally smaller. At birth, an elephant's brain already weighs 30–40% of its adult weight. The cerebrum and cerebellum are well developed, and the temporal lobes are so large that they bulge out laterally.[69] The throat of an elephant appears to contain a pouch where it can store water for later use.[6] The larynx of the elephant is the largest known among mammals. The vocal folds are long and are attached close to the epiglottis base. When comparing an elephant's vocal folds to those of a human, an elephant's are longer, thicker, and have a larger cross-sectional area. In addition, they are tilted at 45 degrees and positioned more anteriorly than a human's vocal folds.[70]

 

The heart of an elephant weighs 12–21 kg (26–46 lb). It has a double-pointed apex, an unusual trait among mammals.[69] In addition, the ventricles separate near the top of the heart, a trait they share with sirenians.[71] When standing, the elephant's heart beats approximately 30 times per minute. Unlike many other animals, the heart rate speeds up by 8 to 10 beats per minute when the elephant is lying down.[72] The blood vessels in most of the body are wide and thick and can withstand high blood pressures.[71] The lungs are attached to the diaphragm, and breathing relies mainly on the diaphragm rather than the expansion of the ribcage.[69] Connective tissue exists in place of the pleural cavity. This may allow the animal to deal with the pressure differences when its body is underwater and its trunk is breaking the surface for air,[32] although this explanation has been questioned.[73] Another possible function for this adaptation is that it helps the animal suck up water through the trunk.[32] Elephants inhale mostly through the trunk, although some air goes through the mouth. They have a hindgut fermentation system, and their large and small intestines together reach 35 m (115 ft) in length. The majority of an elephant's food intake goes undigested despite the process lasting up to a day.[69]

 

A male elephant's testes are located internally near the kidneys.[74] The elephant's penis can reach a length of 100 cm (39 in) and a diameter of 16 cm (6 in) at the base. It is S-shaped when fully erect and has a Y-shaped orifice. The female has a well-developed clitoris at up to 40 cm (16 in). The vulva is located between the hind legs instead of near the tail as in most mammals. Determining pregnancy status can be difficult due to the animal's large abdominal cavity. The female's mammary glands occupy the space between the front legs, which puts the suckling calf within reach of the female's trunk.[69] Elephants have a unique organ, the temporal gland, located in both sides of the head. This organ is associated with sexual behaviour, and males secrete a fluid from it when in musth.[75] Females have also been observed with secretions from the temporal glands.[45]

 

Body temperature

Elephants are homeotherms, and maintain their average body temperature at ~ 36 °C, with minimum 35.2 °C during cool season, and maximum 38.0 °C during hot dry season.[76] Sweat glands are absent in the elephant's skin, but water diffuses through the skin, allowing cooling by evaporative loss.[77][78][79] Other physiological or behavioral features may assist with thermoregulation such as flapping ears,[80] mud bathing, spraying water on the skin, seeking shade,[76][81] and adopting different walking patterns.[82] In addition, the interconnected crevices in the elephant's skin is thought to impede dehydration and improve thermal regulation over a long period of time.[83]