View allAll Photos Tagged behavior
By request. Claudia -- I saw a cardinal doing this about a week ago, too. The first bird I ever saw this behavior in was a Red-bellied Woodpecker on top of its bird house -- I thought it was sick and dying. ;-)
Here's something about it on eNature: www.enature.com/articles/detail.asp?storyID=389
THEY CAME TO KANSAS CITY, MO ON JULY 9TH 2013 & TURNT IT UP!!! THE YOUNG GUY IN THE MIDDLE IS CD AKA PRODIGYY
Jorge Villegas, professor of business administration, speaks with students in his Consumer Behavior course as they present projects on their special possessions. The projects are designed to demonstrate the students' understanding of special possessions and brands, as discussed in class, and to provide an opportunity to connect with a small audience.
How to save your key people and company from sex addiction disasters
Disaster! 6:13 pm, manager Trisha Woodard stops into her vice president’s office for discussion, interrupting him looking at his iPod and masturbating.
Who risks like this at work? Sexually compulsive people escape life’s pain a...
The horse (Equus caballus) is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of Equus ferus. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature, close to Eohippus, into the large, single-toed animal of today. Humans began domesticating horses around 4000 BCE, and their domestication is believed to have been widespread by 3000 BCE. Horses in the subspecies caballus are domesticated, although some domesticated populations live in the wild as feral horses. These feral populations are not true wild horses, which are horses that never have been domesticated. There is an extensive, specialized vocabulary used to describe equine-related concepts, covering everything from anatomy to life stages, size, colors, markings, breeds, locomotion, and behavior.
Horses are adapted to run, allowing them to quickly escape predators, and possess an excellent sense of balance and a strong fight-or-flight response. Related to this need to flee from predators in the wild is an unusual trait: horses are able to sleep both standing up and lying down, with younger horses tending to sleep significantly more than adults. Female horses, called mares, carry their young for approximately 11 months and a young horse, called a foal, can stand and run shortly following birth. Most domesticated horses begin training under a saddle or in a harness between the ages of two and four. They reach full adult development by age five, and have an average lifespan of between 25 and 30 years.
Horse breeds are loosely divided into three categories based on general temperament: spirited "hot bloods" with speed and endurance; "cold bloods", such as draft horses and some ponies, suitable for slow, heavy work; and "warmbloods", developed from crosses between hot bloods and cold bloods, often focusing on creating breeds for specific riding purposes, particularly in Europe. There are more than 300 breeds of horse in the world today, developed for many different uses.
Horses and humans interact in a wide variety of sport competitions and non-competitive recreational pursuits as well as in working activities such as police work, agriculture, entertainment, and therapy. Horses were historically used in warfare, from which a wide variety of riding and driving techniques developed, using many different styles of equipment and methods of control. Many products are derived from horses, including meat, milk, hide, hair, bone, and pharmaceuticals extracted from the urine of pregnant mares. Humans provide domesticated horses with food, water, and shelter, as well as attention from specialists such as veterinarians and farriers.
Lifespan and life stages
Depending on breed, management and environment, the modern domestic horse has a life expectancy of 25 to 30 years. Uncommonly, a few animals live into their 40s and, occasionally, beyond. The oldest verifiable record was "Old Billy", a 19th-century horse that lived to the age of 62. In modern times, Sugar Puff, who had been listed in Guinness World Records as the world's oldest living pony, died in 2007 at age 56.
Regardless of a horse or pony's actual birth date, for most competition purposes a year is added to its age each January 1 of each year in the Northern Hemisphere and each August 1 in the Southern Hemisphere. The exception is in endurance riding, where the minimum age to compete is based on the animal's actual calendar age.
The following terminology is used to describe horses of various ages:
Foal
A horse of either sex less than one year old. A nursing foal is sometimes called a suckling, and a foal that has been weaned is called a weanling. Most domesticated foals are weaned at five to seven months of age, although foals can be weaned at four months with no adverse physical effects.
Yearling
A horse of either sex that is between one and two years old.
Colt
A male horse under the age of four. A common terminology error is to call any young horse a "colt", when the term actually only refers to young male horses.
Filly
A female horse under the age of four.
Mare
A female horse four years old and older.
Stallion
A non-castrated male horse four years old and older.The term "horse" is sometimes used colloquially to refer specifically to a stallion.
Gelding
A castrated male horse of any age.
In horse racing, these definitions may differ: For example, in the British Isles, Thoroughbred horse racing defines colts and fillies as less than five years old. However, Australian Thoroughbred racing defines colts and fillies as less than four years old.
Size and measurement
The height of horses is measured at the highest point of the withers, where the neck meets the back. This point is used because it is a stable point of the anatomy, unlike the head or neck, which move up and down in relation to the body of the horse.
Size varies greatly among horse breeds, as with this full-sized horse and small pony.
In English-speaking countries, the height of horses is often stated in units of hands and inches: one hand is equal to 4 inches (101.6 mm). The height is expressed as the number of full hands, followed by a point, then the number of additional inches, and ending with the abbreviation "h" or "hh" (for "hands high"). Thus, a horse described as "15.2 h" is 15 hands plus 2 inches, for a total of 62 inches (157.5 cm) in height.
The size of horses varies by breed, but also is influenced by nutrition. Light-riding horses usually range in height from 14 to 16 hands (56 to 64 inches, 142 to 163 cm) and can weigh from 380 to 550 kilograms (840 to 1,210 lb). Larger-riding horses usually start at about 15.2 hands (62 inches, 157 cm) and often are as tall as 17 hands (68 inches, 173 cm), weighing from 500 to 600 kilograms (1,100 to 1,320 lb). Heavy or draft horses are usually at least 16 hands (64 inches, 163 cm) high and can be as tall as 18 hands (72 inches, 183 cm) high. They can weigh from about 700 to 1,000 kilograms (1,540 to 2,200 lb).
The largest horse in recorded history was probably a Shire horse named Mammoth, who was born in 1848. He stood 21.2 1⁄4 hands (86.25 inches, 219 cm) high and his peak weight was estimated at 1,524 kilograms (3,360 lb). The record holder for the smallest horse ever is Thumbelina, a fully mature miniature horse affected by dwarfism. She was 43 centimetres; 4.1 hands (17 in) tall and weighed 26 kg (57 lb).
Ponies
Main article: Pony
Ponies are taxonomically the same animals as horses. The distinction between a horse and pony is commonly drawn on the basis of height, especially for competition purposes. However, height alone is not dispositive; the difference between horses and ponies may also include aspects of phenotype, including conformation and temperament.
The traditional standard for height of a horse or a pony at maturity is 14.2 hands (58 inches, 147 cm). An animal 14.2 hands (58 inches, 147 cm) or over is usually considered to be a horse and one less than 14.2 hands (58 inches, 147 cm) a pony, but there are many exceptions to the traditional standard. In Australia, ponies are considered to be those under 14 hands (56 inches, 142 cm). For competition in the Western division of the United States Equestrian Federation, the cutoff is 14.1 hands (57 inches, 145 cm). The International Federation for Equestrian Sports, the world governing body for horse sport, uses metric measurements and defines a pony as being any horse measuring less than 148 centimetres (58.27 in) at the withers without shoes, which is just over 14.2 hands (58 inches, 147 cm), and 149 centimetres (58.66 in; 14.2+1⁄2 hands), with shoes.
Height is not the sole criterion for distinguishing horses from ponies. Breed registries for horses that typically produce individuals both under and over 14.2 hands (58 inches, 147 cm) consider all animals of that breed to be horses regardless of their height. Conversely, some pony breeds may have features in common with horses, and individual animals may occasionally mature at over 14.2 hands (58 inches, 147 cm), but are still considered to be ponies.
Ponies often exhibit thicker manes, tails, and overall coat. They also have proportionally shorter legs, wider barrels, heavier bone, shorter and thicker necks, and short heads with broad foreheads. They may have calmer temperaments than horses and also a high level of intelligence that may or may not be used to cooperate with human handlers. Small size, by itself, is not an exclusive determinant. For example, the Shetland pony which averages 10 hands (40 inches, 102 cm), is considered a pony. Conversely, breeds such as the Falabella and other miniature horses, which can be no taller than 76 centimetres; 7.2 hands (30 in), are classified by their registries as very small horses, not ponies.
Genetics
Horses have 64 chromosomes. The horse genome was sequenced in 2007. It contains 2.7 billion DNA base pairs, which is larger than the dog genome, but smaller than the human genome or the bovine genome.
Colors and markings
Horses exhibit a diverse array of coat colors and distinctive markings, described by a specialized vocabulary. Often, a horse is classified first by its coat color, before breed or sex. Horses of the same color may be distinguished from one another by white markings, which, along with various spotting patterns, are inherited separately from coat color.
Many genes that create horse coat colors and patterns have been identified. Current genetic tests can identify at least 13 different alleles influencing coat color, and research continues to discover new genes linked to specific traits. The basic coat colors of chestnut and black are determined by the gene controlled by the Melanocortin 1 receptor, also known as the "extension gene" or "red factor", as its recessive form is "red" (chestnut) and its dominant form is black. Additional genes control suppression of black color to point coloration that results in a bay, spotting patterns such as pinto or leopard, dilution genes such as palomino or dun, as well as greying, and all the other factors that create the many possible coat colors found in horses.
Horses that have a white coat color are often mislabeled; a horse that looks "white" is usually a middle-aged or older gray. Grays are born a darker shade, get lighter as they age, but usually keep black skin underneath their white hair coat (with the exception of pink skin under white markings). The only horses properly called white are born with a predominantly white hair coat and pink skin, a fairly rare occurrence. Different and unrelated genetic factors can produce white coat colors in horses, including several different alleles of dominant white and the sabino-1 gene. However, there are no "albino" horses, defined as having both pink skin and red eyes.
Reproduction and development
Gestation lasts approximately 340 days, with an average range 320–370 days, and usually results in one foal; twins are rare. Horses are a precocial species, and foals are capable of standing and running within a short time following birth. Foals are usually born in the spring. The estrous cycle of a mare occurs roughly every 19–22 days and occurs from early spring into autumn. Most mares enter an anestrus period during the winter and thus do not cycle in this period. Foals are generally weaned from their mothers between four and six months of age.
Horses, particularly colts, are sometimes physically capable of reproduction at about 18 months, but domesticated horses are rarely allowed to breed before the age of three, especially females. Horses four years old are considered mature, although the skeleton normally continues to develop until the age of six; maturation also depends on the horse's size, breed, sex, and quality of care. Larger horses have larger bones; therefore, not only do the bones take longer to form bone tissue, but the epiphyseal plates are larger and take longer to convert from cartilage to bone. These plates convert after the other parts of the bones, and are crucial to development.
Depending on maturity, breed, and work expected, horses are usually put under saddle and trained to be ridden between the ages of two and four. Although Thoroughbred race horses are put on the track as young as the age of two in some countries, horses specifically bred for sports such as dressage are generally not put under saddle until they are three or four years old, because their bones and muscles are not solidly developed. For endurance riding competition, horses are not deemed mature enough to compete until they are a full 60 calendar months (five years) old.
Anatomy
The horse skeleton averages 205 bones. A significant difference between the horse skeleton and that of a human is the lack of a collarbone—the horse's forelimbs are attached to the spinal column by a powerful set of muscles, tendons, and ligaments that attach the shoulder blade to the torso. The horse's four legs and hooves are also unique structures. Their leg bones are proportioned differently from those of a human. For example, the body part that is called a horse's "knee" is actually made up of the carpal bones that correspond to the human wrist. Similarly, the hock contains bones equivalent to those in the human ankle and heel. The lower leg bones of a horse correspond to the bones of the human hand or foot, and the fetlock (incorrectly called the "ankle") is actually the proximal sesamoid bones between the cannon bones (a single equivalent to the human metacarpal or metatarsal bones) and the proximal phalanges, located where one finds the "knuckles" of a human. A horse also has no muscles in its legs below the knees and hocks, only skin, hair, bone, tendons, ligaments, cartilage, and the assorted specialized tissues that make up the hoof.
Hooves
Main articles: Horse hoof, Horseshoe, and Farrier
The critical importance of the feet and legs is summed up by the traditional adage, "no foot, no horse". The horse hoof begins with the distal phalanges, the equivalent of the human fingertip or tip of the toe, surrounded by cartilage and other specialized, blood-rich soft tissues such as the laminae. The exterior hoof wall and horn of the sole is made of keratin, the same material as a human fingernail. The result is that a horse, weighing on average 500 kilograms (1,100 lb), travels on the same bones as would a human on tiptoe. For the protection of the hoof under certain conditions, some horses have horseshoes placed on their feet by a professional farrier. The hoof continually grows, and in most domesticated horses needs to be trimmed (and horseshoes reset, if used) every five to eight weeks, though the hooves of horses in the wild wear down and regrow at a rate suitable for their terrain.
Teeth
Main article: Horse teeth
Horses are adapted to grazing. In an adult horse, there are 12 incisors at the front of the mouth, adapted to biting off the grass or other vegetation. There are 24 teeth adapted for chewing, the premolars and molars, at the back of the mouth. Stallions and geldings have four additional teeth just behind the incisors, a type of canine teeth called "tushes". Some horses, both male and female, will also develop one to four very small vestigial teeth in front of the molars, known as "wolf" teeth, which are generally removed because they can interfere with the bit. There is an empty interdental space between the incisors and the molars where the bit rests directly on the gums, or "bars" of the horse's mouth when the horse is bridled.
An estimate of a horse's age can be made from looking at its teeth. The teeth continue to erupt throughout life and are worn down by grazing. Therefore, the incisors show changes as the horse ages; they develop a distinct wear pattern, changes in tooth shape, and changes in the angle at which the chewing surfaces meet. This allows a very rough estimate of a horse's age, although diet and veterinary care can also affect the rate of tooth wear.
Digestion
Main articles: Equine digestive system and Equine nutrition
Horses are herbivores with a digestive system adapted to a forage diet of grasses and other plant material, consumed steadily throughout the day. Therefore, compared to humans, they have a relatively small stomach but very long intestines to facilitate a steady flow of nutrients. A 450-kilogram (990 lb) horse will eat 7 to 11 kilograms (15 to 24 lb) of food per day and, under normal use, drink 38 to 45 litres (8.4 to 9.9 imp gal; 10 to 12 US gal) of water. Horses are not ruminants, they have only one stomach, like humans, but unlike humans, they can digest cellulose, a major component of grass. Horses are hindgut fermenters. Cellulose fermentation by symbiotic bacteria occurs in the cecum, or "water gut", which food goes through before reaching the large intestine. Horses cannot vomit, so digestion problems can quickly cause colic, a leading cause of death. Horses do not have a gallbladder; however, they seem to tolerate high amounts of fat in their diet despite lack of a gallbladder.
Senses
The horses' senses are based on their status as prey animals, where they must be aware of their surroundings at all times. They have the largest eyes of any land mammal, and are lateral-eyed, meaning that their eyes are positioned on the sides of their heads. This means that horses have a range of vision of more than 350°, with approximately 65° of this being binocular vision and the remaining 285° monocular vision. Horses have excellent day and night vision, but they have two-color, or dichromatic vision; their color vision is somewhat like red-green color blindness in humans, where certain colors, especially red and related colors, appear as a shade of green.
Their sense of smell, while much better than that of humans, is not quite as good as that of a dog. It is believed to play a key role in the social interactions of horses as well as detecting other key scents in the environment. Horses have two olfactory centers. The first system is in the nostrils and nasal cavity, which analyze a wide range of odors. The second, located under the nasal cavity, are the vomeronasal organs, also called Jacobson's organs. These have a separate nerve pathway to the brain and appear to primarily analyze pheromones.
A horse's hearing is good, and the pinna of each ear can rotate up to 180°, giving the potential for 360° hearing without having to move the head. Noise impacts the behavior of horses and certain kinds of noise may contribute to stress: a 2013 study in the UK indicated that stabled horses were calmest in a quiet setting, or if listening to country or classical music, but displayed signs of nervousness when listening to jazz or rock music. This study also recommended keeping music under a volume of 21 decibels. An Australian study found that stabled racehorses listening to talk radio had a higher rate of gastric ulcers than horses listening to music, and racehorses stabled where a radio was played had a higher overall rate of ulceration than horses stabled where there was no radio playing.
Horses have a great sense of balance, due partly to their ability to feel their footing and partly to highly developed proprioception—the unconscious sense of where the body and limbs are at all times. A horse's sense of touch is well-developed. The most sensitive areas are around the eyes, ears, and nose. Horses are able to sense contact as subtle as an insect landing anywhere on the body.
Horses have an advanced sense of taste, which allows them to sort through fodder and choose what they would most like to eat, and their prehensile lips can easily sort even small grains. Horses generally will not eat poisonous plants, however, there are exceptions; horses will occasionally eat toxic amounts of poisonous plants even when there is adequate healthy food.
Movement
All horses move naturally with four basic gaits:
the four-beat walk, which averages 6.4 kilometres per hour (4.0 mph);
the two-beat trot or jog at 13 to 19 kilometres per hour (8.1 to 11.8 mph) (faster for harness racing horses);
the canter or lope, a three-beat gait that is 19 to 24 kilometres per hour (12 to 15 mph);
the gallop, which averages 40 to 48 kilometres per hour (25 to 30 mph), but the world record for a horse galloping over a short, sprint distance is 70.76 kilometres per hour (43.97 mph).
Besides these basic gaits, some horses perform a two-beat pace, instead of the trot. There also are several four-beat 'ambling' gaits that are approximately the speed of a trot or pace, though smoother to ride. These include the lateral rack, running walk, and tölt as well as the diagonal fox trot. Ambling gaits are often genetic in some breeds, known collectively as gaited horses. These horses replace the trot with one of the ambling gaits.
Behavior
Horses are prey animals with a strong fight-or-flight response. Their first reaction to a threat is to startle and usually flee, although they will stand their ground and defend themselves when flight is impossible or if their young are threatened. They also tend to be curious; when startled, they will often hesitate an instant to ascertain the cause of their fright, and may not always flee from something that they perceive as non-threatening. Most light horse riding breeds were developed for speed, agility, alertness and endurance; natural qualities that extend from their wild ancestors. However, through selective breeding, some breeds of horses are quite docile, particularly certain draft horses.
Horses fighting as part of herd dominance behaviour
Horses are herd animals, with a clear hierarchy of rank, led by a dominant individual, usually a mare. They are also social creatures that are able to form companionship attachments to their own species and to other animals, including humans. They communicate in various ways, including vocalizations such as nickering or whinnying, mutual grooming, and body language. Many horses will become difficult to manage if they are isolated, but with training, horses can learn to accept a human as a companion, and thus be comfortable away from other horses. However, when confined with insufficient companionship, exercise, or stimulation, individuals may develop stable vices, an assortment of bad habits, mostly stereotypies of psychological origin, that include wood chewing, wall kicking, "weaving" (rocking back and forth), and other problems.
Intelligence and learning
Studies have indicated that horses perform a number of cognitive tasks on a daily basis, meeting mental challenges that include food procurement and identification of individuals within a social system. They also have good spatial discrimination abilities. They are naturally curious and apt to investigate things they have not seen before. Studies have assessed equine intelligence in areas such as problem solving, speed of learning, and memory. Horses excel at simple learning, but also are able to use more advanced cognitive abilities that involve categorization and concept learning. They can learn using habituation, desensitization, classical conditioning, and operant conditioning, and positive and negative reinforcement. One study has indicated that horses can differentiate between "more or less" if the quantity involved is less than four.
Domesticated horses may face greater mental challenges than wild horses, because they live in artificial environments that prevent instinctive behavior whilst also learning tasks that are not natural. Horses are animals of habit that respond well to regimentation, and respond best when the same routines and techniques are used consistently. One trainer believes that "intelligent" horses are reflections of intelligent trainers who effectively use response conditioning techniques and positive reinforcement to train in the style that best fits with an individual animal's natural inclinations.
Temperament
Horses are mammals, and as such are warm-blooded, or endothermic creatures, as opposed to cold-blooded, or poikilothermic animals. However, these words have developed a separate meaning in the context of equine terminology, used to describe temperament, not body temperature. For example, the "hot-bloods", such as many race horses, exhibit more sensitivity and energy, while the "cold-bloods", such as most draft breeds, are quieter and calmer. Sometimes "hot-bloods" are classified as "light horses" or "riding horses", with the "cold-bloods" classified as "draft horses" or "work horses".
a sepia-toned engraving from an old book, showing 11 horses of different breeds and sizes in nine different illustrations
Illustration of assorted breeds; slim, light hotbloods, medium-sized warmbloods and draft and pony-type coldblood breeds
"Hot blooded" breeds include "oriental horses" such as the Akhal-Teke, Arabian horse, Barb, and now-extinct Turkoman horse, as well as the Thoroughbred, a breed developed in England from the older oriental breeds. Hot bloods tend to be spirited, bold, and learn quickly. They are bred for agility and speed. They tend to be physically refined—thin-skinned, slim, and long-legged. The original oriental breeds were brought to Europe from the Middle East and North Africa when European breeders wished to infuse these traits into racing and light cavalry horses.
Muscular, heavy draft horses are known as "cold bloods", as they are bred not only for strength, but also to have the calm, patient temperament needed to pull a plow or a heavy carriage full of people. They are sometimes nicknamed "gentle giants". Well-known draft breeds include the Belgian and the Clydesdale. Some, like the Percheron, are lighter and livelier, developed to pull carriages or to plow large fields in drier climates. Others, such as the Shire, are slower and more powerful, bred to plow fields with heavy, clay-based soils. The cold-blooded group also includes some pony breeds.
"Warmblood" breeds, such as the Trakehner or Hanoverian, developed when European carriage and war horses were crossed with Arabians or Thoroughbreds, producing a riding horse with more refinement than a draft horse, but greater size and milder temperament than a lighter breed. Certain pony breeds with warmblood characteristics have been developed for smaller riders. Warmbloods are considered a "light horse" or "riding horse".
Today, the term "Warmblood" refers to a specific subset of sport horse breeds that are used for competition in dressage and show jumping. Strictly speaking, the term "warm blood" refers to any cross between cold-blooded and hot-blooded breeds. Examples include breeds such as the Irish Draught or the Cleveland Bay. The term was once used to refer to breeds of light riding horse other than Thoroughbreds or Arabians, such as the Morgan horse.
Sleep patterns
When horses lie down to sleep, others in the herd remain standing, awake, or in a light doze, keeping watch.
Horses are able to sleep both standing up and lying down. In an adaptation from life in the wild, horses are able to enter light sleep by using a "stay apparatus" in their legs, allowing them to doze without collapsing. Horses sleep better when in groups because some animals will sleep while others stand guard to watch for predators. A horse kept alone will not sleep well because its instincts are to keep a constant eye out for danger.
Unlike humans, horses do not sleep in a solid, unbroken period of time, but take many short periods of rest. Horses spend four to fifteen hours a day in standing rest, and from a few minutes to several hours lying down. Total sleep time in a 24-hour period may range from several minutes to a couple of hours, mostly in short intervals of about 15 minutes each. The average sleep time of a domestic horse is said to be 2.9 hours per day.
Horses must lie down to reach REM sleep. They only have to lie down for an hour or two every few days to meet their minimum REM sleep requirements. However, if a horse is never allowed to lie down, after several days it will become sleep-deprived, and in rare cases may suddenly collapse as it involuntarily slips into REM sleep while still standing. This condition differs from narcolepsy, although horses may also suffer from that disorder.
Taxonomy and evolution
The horse adapted to survive in areas of wide-open terrain with sparse vegetation, surviving in an ecosystem where other large grazing animals, especially ruminants, could not. Horses and other equids are odd-toed ungulates of the order Perissodactyla, a group of mammals dominant during the Tertiary period. In the past, this order contained 14 families, but only three—Equidae (the horse and related species), Tapiridae (the tapir), and Rhinocerotidae (the rhinoceroses)—have survived to the present day.
The earliest known member of the family Equidae was the Hyracotherium, which lived between 45 and 55 million years ago, during the Eocene period. It had 4 toes on each front foot, and 3 toes on each back foot. The extra toe on the front feet soon disappeared with the Mesohippus, which lived 32 to 37 million years ago. Over time, the extra side toes shrank in size until they vanished. All that remains of them in modern horses is a set of small vestigial bones on the leg below the knee, known informally as splint bones. Their legs also lengthened as their toes disappeared until they were a hooved animal capable of running at great speed. By about 5 million years ago, the modern Equus had evolved. Equid teeth also evolved from browsing on soft, tropical plants to adapt to browsing of drier plant material, then to grazing of tougher plains grasses. Thus proto-horses changed from leaf-eating forest-dwellers to grass-eating inhabitants of semi-arid regions worldwide, including the steppes of Eurasia and the Great Plains of North America.
By about 15,000 years ago, Equus ferus was a widespread holarctic species. Horse bones from this time period, the late Pleistocene, are found in Europe, Eurasia, Beringia, and North America. Yet between 10,000 and 7,600 years ago, the horse became extinct in North America. The reasons for this extinction are not fully known, but one theory notes that extinction in North America paralleled human arrival. Another theory points to climate change, noting that approximately 12,500 years ago, the grasses characteristic of a steppe ecosystem gave way to shrub tundra, which was covered with unpalatable plants.
Wild species surviving into modern times
Three tan-colored horses with upright manes. Two horses nip and paw at each other, while the third moves towards the camera. They stand in an open, rocky grassland, with forests in the distance.
Main article: Wild horse
A truly wild horse is a species or subspecies with no ancestors that were ever successfully domesticated. Therefore, most "wild" horses today are actually feral horses, animals that escaped or were turned loose from domestic herds and the descendants of those animals. Only two wild subspecies, the tarpan and the Przewalski's horse, survived into recorded history and only the latter survives today.
The Przewalski's horse (Equus ferus przewalskii), named after the Russian explorer Nikolai Przhevalsky, is a rare Asian animal. It is also known as the Mongolian wild horse; Mongolian people know it as the taki, and the Kyrgyz people call it a kirtag. The subspecies was presumed extinct in the wild between 1969 and 1992, while a small breeding population survived in zoos around the world. In 1992, it was reestablished in the wild by the conservation efforts of numerous zoos. Today, a small wild breeding population exists in Mongolia. There are additional animals still maintained at zoos throughout the world.
The question of whether the Przewalski's horse was ever domesticated was challenged in 2018 when DNA studies of horses found at Botai culture sites revealed captured animals with DNA markers of an ancestor to the Przewalski's horse. The study concluded that the Botai animals appear to have been an independent domestication attempt and apparently unsuccessful, as these genetic markers do not appear in modern domesticated horses. However, the question of whether all Przewalski's horses descend from this population is also unresolved, as only one of seven modern Przewalski's horses in the study shared this ancestry.
The tarpan or European wild horse (Equus ferus ferus) was found in Europe and much of Asia. It survived into the historical era, but became extinct in 1909, when the last captive died in a Russian zoo. Thus, the genetic line was lost. Attempts have been made to recreate the tarpan, which resulted in horses with outward physical similarities, but nonetheless descended from domesticated ancestors and not true wild horses.
Periodically, populations of horses in isolated areas are speculated to be relict populations of wild horses, but generally have been proven to be feral or domestic. For example, the Riwoche horse of Tibet was proposed as such, but testing did not reveal genetic differences from domesticated horses. Similarly, the Sorraia of Portugal was proposed as a direct descendant of the Tarpan on the basis of shared characteristics, but genetic studies have shown that the Sorraia is more closely related to other horse breeds, and that the outward similarity is an unreliable measure of relatedness.
Other modern equids
Main article: Equus (genus)
Besides the horse, there are six other species of genus Equus in the Equidae family. These are the ass or donkey, Equus asinus; the mountain zebra, Equus zebra; plains zebra, Equus quagga; Grévy's Zebra, Equus grevyi; the kiang, Equus kiang; and the onager, Equus hemionus.
Horses can crossbreed with other members of their genus. The most common hybrid is the mule, a cross between a "jack" (male donkey) and a mare. A related hybrid, a hinny, is a cross between a stallion and a "jenny" (female donkey). Other hybrids include the zorse, a cross between a zebra and a horse. With rare exceptions, most hybrids are sterile and cannot reproduce.
Main articles: History of horse domestication theories and Domestication of the horse
Domestication of the horse most likely took place in central Asia prior to 3500 BCE. Two major sources of information are used to determine where and when the horse was first domesticated and how the domesticated horse spread around the world. The first source is based on palaeological and archaeological discoveries; the second source is a comparison of DNA obtained from modern horses to that from bones and teeth of ancient horse remains.
The earliest archaeological evidence for the domestication of the horse comes from sites in Ukraine and Kazakhstan, dating to approximately 4000–3500 BCE. By 3000 BCE, the horse was completely domesticated and by 2000 BCE there was a sharp increase in the number of horse bones found in human settlements in northwestern Europe, indicating the spread of domesticated horses throughout the continent. The most recent, but most irrefutable evidence of domestication comes from sites where horse remains were interred with chariots in graves of the Sintashta and Petrovka cultures c. 2100 BCE.
A 2021 genetic study suggested that most modern domestic horses descend from the lower Volga-Don region. Ancient horse genomes indicate that these populations influenced almost all local populations as they expanded rapidly throughout Eurasia, beginning about 4,200 years ago. It also shows that certain adaptations were strongly selected due to riding, and that equestrian material culture, including Sintashta spoke-wheeled chariots spread with the horse itself.
Domestication is also studied by using the genetic material of present-day horses and comparing it with the genetic material present in the bones and teeth of horse remains found in archaeological and palaeological excavations. The variation in the genetic material shows that very few wild stallions contributed to the domestic horse, while many mares were part of early domesticated herds. This is reflected in the difference in genetic variation between the DNA that is passed on along the paternal, or sire line (Y-chromosome) versus that passed on along the maternal, or dam line (mitochondrial DNA). There are very low levels of Y-chromosome variability, but a great deal of genetic variation in mitochondrial DNA. There is also regional variation in mitochondrial DNA due to the inclusion of wild mares in domestic herds. Another characteristic of domestication is an increase in coat color variation. In horses, this increased dramatically between 5000 and 3000 BCE.
Before the availability of DNA techniques to resolve the questions related to the domestication of the horse, various hypotheses were proposed. One classification was based on body types and conformation, suggesting the presence of four basic prototypes that had adapted to their environment prior to domestication. Another hypothesis held that the four prototypes originated from a single wild species and that all different body types were entirely a result of selective breeding after domestication. However, the lack of a detectable substructure in the horse has resulted in a rejection of both hypotheses.
Main article: Feral horse
Feral horses are born and live in the wild, but are descended from domesticated animals. Many populations of feral horses exist throughout the world. Studies of feral herds have provided useful insights into the behavior of prehistoric horses, as well as greater understanding of the instincts and behaviors that drive horses that live in domesticated conditions.
There are also semi-feral horses in many parts of the world, such as Dartmoor and the New Forest in the UK, where the animals are all privately owned but live for significant amounts of time in "wild" conditions on undeveloped, often public, lands. Owners of such animals often pay a fee for grazing rights.
Main articles: Horse breed, List of horse breeds, and Horse breeding
The concept of purebred bloodstock and a controlled, written breed registry has come to be particularly significant and important in modern times. Sometimes purebred horses are incorrectly or inaccurately called "thoroughbreds". Thoroughbred is a specific breed of horse, while a "purebred" is a horse (or any other animal) with a defined pedigree recognized by a breed registry. Horse breeds are groups of horses with distinctive characteristics that are transmitted consistently to their offspring, such as conformation, color, performance ability, or disposition. These inherited traits result from a combination of natural crosses and artificial selection methods. Horses have been selectively bred since their domestication. An early example of people who practiced selective horse breeding were the Bedouin, who had a reputation for careful practices, keeping extensive pedigrees of their Arabian horses and placing great value upon pure bloodlines. These pedigrees were originally transmitted via an oral tradition. In the 14th century, Carthusian monks of southern Spain kept meticulous pedigrees of bloodstock lineages still found today in the Andalusian horse.
Breeds developed due to a need for "form to function", the necessity to develop certain characteristics in order to perform a particular type of work. Thus, a powerful but refined breed such as the Andalusian developed as riding horses with an aptitude for dressage. Heavy draft horses were developed out of a need to perform demanding farm work and pull heavy wagons. Other horse breeds had been developed specifically for light agricultural work, carriage and road work, various sport disciplines, or simply as pets. Some breeds developed through centuries of crossing other breeds, while others descended from a single foundation sire, or other limited or restricted foundation bloodstock. One of the earliest formal registries was General Stud Book for Thoroughbreds, which began in 1791 and traced back to the foundation bloodstock for the breed. There are more than 300 horse breeds in the world today.
Interaction with humans
Worldwide, horses play a role within human cultures and have done so for millennia. Horses are used for leisure activities, sports, and working purposes. The Food and Agriculture Organization (FAO) estimates that in 2008, there were almost 59,000,000 horses in the world, with around 33,500,000 in the Americas, 13,800,000 in Asia and 6,300,000 in Europe and smaller portions in Africa and Oceania. There are estimated to be 9,500,000 horses in the United States alone. The American Horse Council estimates that horse-related activities have a direct impact on the economy of the United States of over $39 billion, and when indirect spending is considered, the impact is over $102 billion. In a 2004 "poll" conducted by Animal Planet, more than 50,000 viewers from 73 countries voted for the horse as the world's 4th favorite animal.
Communication between human and horse is paramount in any equestrian activity; to aid this process horses are usually ridden with a saddle on their backs to assist the rider with balance and positioning, and a bridle or related headgear to assist the rider in maintaining control. Sometimes horses are ridden without a saddle, and occasionally, horses are trained to perform without a bridle or other headgear. Many horses are also driven, which requires a harness, bridle, and some type of vehicle.
Main articles: Equestrianism, Horse racing, Horse training, and Horse tack
Historically, equestrians honed their skills through games and races. Equestrian sports provided entertainment for crowds and honed the excellent horsemanship that was needed in battle. Many sports, such as dressage, eventing, and show jumping, have origins in military training, which were focused on control and balance of both horse and rider. Other sports, such as rodeo, developed from practical skills such as those needed on working ranches and stations. Sport hunting from horseback evolved from earlier practical hunting techniques. Horse racing of all types evolved from impromptu competitions between riders or drivers. All forms of competition, requiring demanding and specialized skills from both horse and rider, resulted in the systematic development of specialized breeds and equipment for each sport. The popularity of equestrian sports through the centuries has resulted in the preservation of skills that would otherwise have disappeared after horses stopped being used in combat.
Horses are trained to be ridden or driven in a variety of sporting competitions. Examples include show jumping, dressage, three-day eventing, competitive driving, endurance riding, gymkhana, rodeos, and fox hunting. Horse shows, which have their origins in medieval European fairs, are held around the world. They host a huge range of classes, covering all of the mounted and harness disciplines, as well as "In-hand" classes where the horses are led, rather than ridden, to be evaluated on their conformation. The method of judging varies with the discipline, but winning usually depends on style and ability of both horse and rider. Sports such as polo do not judge the horse itself, but rather use the horse as a partner for human competitors as a necessary part of the game. Although the horse requires specialized training to participate, the details of its performance are not judged, only the result of the rider's actions—be it getting a ball through a goal or some other task. Examples of these sports of partnership between human and horse include jousting, in which the main goal is for one rider to unseat the other, and buzkashi, a team game played throughout Central Asia, the aim being to capture a goat carcass while on horseback.
Horse racing is an equestrian sport and major international industry, watched in almost every nation of the world. There are three types: "flat" racing; steeplechasing, i.e. racing over jumps; and harness racing, where horses trot or pace while pulling a driver in a small, light cart known as a sulky. A major part of horse racing's economic importance lies in the gambling associated with it.
Work
There are certain jobs that horses do very well, and no technology has yet developed to fully replace them. For example, mounted police horses are still effective for certain types of patrol duties and crowd control. Cattle ranches still require riders on horseback to round up cattle that are scattered across remote, rugged terrain. Search and rescue organizations in some countries depend upon mounted teams to locate people, particularly hikers and children, and to provide disaster relief assistance. Horses can also be used in areas where it is necessary to avoid vehicular disruption to delicate soil, such as nature reserves. They may also be the only form of transport allowed in wilderness areas. Horses are quieter than motorized vehicles. Law enforcement officers such as park rangers or game wardens may use horses for patrols, and horses or mules may also be used for clearing trails or other work in areas of rough terrain where vehicles are less effective.
Although machinery has replaced horses in many parts of the world, an estimated 100 million horses, donkeys and mules are still used for agriculture and transportation in less developed areas. This number includes around 27 million working animals in Africa alone. Some land management practices such as cultivating and logging can be efficiently performed with horses. In agriculture, less fossil fuel is used and increased environmental conservation occurs over time with the use of draft animals such as horses. Logging with horses can result in reduced damage to soil structure and less damage to trees due to more selective logging.
Main article: Horses in warfare
Horses have been used in warfare for most of recorded history. The first archaeological evidence of horses used in warfare dates to between 4000 and 3000 BCE, and the use of horses in warfare was widespread by the end of the Bronze Age. Although mechanization has largely replaced the horse as a weapon of war, horses are still seen today in limited military uses, mostly for ceremonial purposes, or for reconnaissance and transport activities in areas of rough terrain where motorized vehicles are ineffective. Horses have been used in the 21st century by the Janjaweed militias in the War in Darfur.
Entertainment and culture
Modern horses are often used to reenact many of their historical work purposes. Horses are used, complete with equipment that is authentic or a meticulously recreated replica, in various live action historical reenactments of specific periods of history, especially recreations of famous battles. Horses are also used to preserve cultural traditions and for ceremonial purposes. Countries such as the United Kingdom still use horse-drawn carriages to convey royalty and other VIPs to and from certain culturally significant events. Public exhibitions are another example, such as the Budweiser Clydesdales, seen in parades and other public settings, a team of draft horses that pull a beer wagon similar to that used before the invention of the modern motorized truck.
Horses are frequently used in television, films and literature. They are sometimes featured as a major character in films about particular animals, but also used as visual elements that assure the accuracy of historical stories. Both live horses and iconic images of horses are used in advertising to promote a variety of products. The horse frequently appears in coats of arms in heraldry, in a variety of poses and equipment. The mythologies of many cultures, including Greco-Roman, Hindu, Islamic, and Germanic, include references to both normal horses and those with wings or additional limbs, and multiple myths also call upon the horse to draw the chariots of the Moon and Sun. The horse also appears in the 12-year cycle of animals in the Chinese zodiac related to the Chinese calendar.
Horses serve as the inspiration for many modern automobile names and logos, including the Ford Pinto, Ford Bronco, Ford Mustang, Hyundai Equus, Hyundai Pony, Mitsubishi Starion, Subaru Brumby, Mitsubishi Colt/Dodge Colt, Pinzgauer, Steyr-Puch Haflinger, Pegaso, Porsche, Rolls-Royce Camargue, Ferrari, Carlsson, Kamaz, Corre La Licorne, Iran Khodro, Eicher, and Baojun. Indian TVS Motor Company also uses a horse on their motorcycles & scooters.
Therapeutic use
People of all ages with physical and mental disabilities obtain beneficial results from an association with horses. Therapeutic riding is used to mentally and physically stimulate disabled persons and help them improve their lives through improved balance and coordination, increased self-confidence, and a greater feeling of freedom and independence. The benefits of equestrian activity for people with disabilities has also been recognized with the addition of equestrian events to the Paralympic Games and recognition of para-equestrian events by the International Federation for Equestrian Sports (FEI). Hippotherapy and therapeutic horseback riding are names for different physical, occupational, and speech therapy treatment strategies that use equine movement. In hippotherapy, a therapist uses the horse's movement to improve their patient's cognitive, coordination, balance, and fine motor skills, whereas therapeutic horseback riding uses specific riding skills.
Horses also provide psychological benefits to people whether they actually ride or not. "Equine-assisted" or "equine-facilitated" therapy is a form of experiential psychotherapy that uses horses as companion animals to assist people with mental illness, including anxiety disorders, psychotic disorders, mood disorders, behavioral difficulties, and those who are going through major life changes. There are also experimental programs using horses in prison settings. Exposure to horses appears to improve the behavior of inmates and help reduce recidivism when they leave.
Products
Horses are raw material for many products made by humans throughout history, including byproducts from the slaughter of horses as well as materials collected from living horses.
Products collected from living horses include mare's milk, used by people with large horse herds, such as the Mongols, who let it ferment to produce kumis. Horse blood was once used as food by the Mongols and other nomadic tribes, who found it a convenient source of nutrition when traveling. Drinking their own horses' blood allowed the Mongols to ride for extended periods of time without stopping to eat. The drug Premarin is a mixture of estrogens extracted from the urine of pregnant mares (pregnant mares' urine), and was previously a widely used drug for hormone replacement therapy. The tail hair of horses can be used for making bows for string instruments such as the violin, viola, cello, and double bass.
Horse meat has been used as food for humans and carnivorous animals throughout the ages. Approximately 5 million horses are slaughtered each year for meat worldwide. It is eaten in many parts of the world, though consumption is taboo in some cultures, and a subject of political controversy in others. Horsehide leather has been used for boots, gloves, jackets, baseballs, and baseball gloves. Horse hooves can also be used to produce animal glue. Horse bones can be used to make implements. Specifically, in Italian cuisine, the horse tibia is sharpened into a probe called a spinto, which is used to test the readiness of a (pig) ham as it cures. In Asia, the saba is a horsehide vessel used in the production of kumis.
Main article: Horse care
Checking teeth and other physical examinations are an important part of horse care.
Horses are grazing animals, and their major source of nutrients is good-quality forage from hay or pasture. They can consume approximately 2% to 2.5% of their body weight in dry feed each day. Therefore, a 450-kilogram (990 lb) adult horse could eat up to 11 kilograms (24 lb) of food. Sometimes, concentrated feed such as grain is fed in addition to pasture or hay, especially when the animal is very active. When grain is fed, equine nutritionists recommend that 50% or more of the animal's diet by weight should still be forage.
Horses require a plentiful supply of clean water, a minimum of 38 to 45 litres (10 to 12 US gal) per day. Although horses are adapted to live outside, they require shelter from the wind and precipitation, which can range from a simple shed or shelter to an elaborate stable.
Horses require routine hoof care from a farrier, as well as vaccinations to protect against various diseases, and dental examinations from a veterinarian or a specialized equine dentist. If horses are kept inside in a barn, they require regular daily exercise for their physical health and mental well-being. When turned outside, they require well-maintained, sturdy fences to be safely contained. Regular grooming is also helpful to help the horse maintain good health of the hair coat and underlying skin.
Climate change
As of 2019, there are around 17 million horses in the world. Healthy body temperature for adult horses is in the range between 37.5 and 38.5 °C (99.5 and 101.3 °F), which they can maintain while ambient temperatures are between 5 and 25 °C (41 and 77 °F). However, strenuous exercise increases core body temperature by 1 °C (1.8 °F)/minute, as 80% of the energy used by equine muscles is released as heat. Along with bovines and primates, equines are the only animal group which use sweating as their primary method of thermoregulation: in fact, it can account for up to 70% of their heat loss, and horses sweat three times more than humans while undergoing comparably strenuous physical activity. Unlike humans, this sweat is created not by eccrine glands but by apocrine glands. In hot conditions, horses during three hours of moderate-intersity exercise can loss 30 to 35 L of water and 100g of sodium, 198 g of choloride and 45 g of potassium. In another difference from humans, their sweat is hypertonic, and contains a protein called latherin, which enables it to spread across their body easier, and to foam, rather than to drip off. These adaptations are partly to compensate for their lower body surface-to-mass ratio, which makes it more difficult for horses to passively radiate heat. Yet, prolonged exposure to very hot and/or humid conditions will lead to consequences such as anhidrosis, heat stroke, or brain damage, potentially culminating in death if not addressed with measures like cold water applications. Additionally, around 10% of incidents associated with horse transport have been attributed to heat stress. These issues are expected to worsen in the future.
African horse sickness (AHS) is a viral illness with a mortality close to 90% in horses, and 50% in mules. A midge, Culicoides imicola, is the primary vector of AHS, and its spread is expected to benefit from climate change. The spillover of Hendra virus from its flying fox hosts to horses is also likely to increase, as future warming would expand the hosts' geographic range. It has been estimated that under the "moderate" and high climate change scenarios, RCP4.5 and RCP8.5, the number of threatened horses would increase by 110,000 and 165,000, respectively, or by 175 and 260%
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As mudanças nos cercam. Nada é imutável. Por mais que façamos tudo igual, a cada dia tudo fica diferente. Temos que estar prontos para as mais inesperadas reviravoltas. Às vezes estamos caminhando para o topo da escada, felizes, e caímos alguns degraus. E o oposto; estamos na nossa subida lenta e contínua e somos "promovidos" a pular alguns degraus. A primeira situação é desconcertante. Construímos passo a passo uma realidade ideal, repleta de sentimentos, ações, processos, e quando tudo parece no lugar, os ventos da mudança aparecem e mudam tudo. É injusto! Às vezes um pouco de inércia e rotina ajudam a nossa mente na organização dos pensamentos. Às vezes a nossa vontade é de dizer para os ventos da mudança: me esqueçam por um tempo, me deixem aqui em paz no ponto que eu cheguei às custas de muita luta e muito suor derramado. Mas os ventos não nos ouvem ou, talvez, saibam melhor que nós a hora de aparecerem.
I have been unable to find an explanation online for the behavior of the emus and the ostriches. Both will snap at fencing and other objects as if they're trying to catch insects flying around the objects. It's December and we have very few insects active outdoors.
If I remember, I'll ask a keeper if it's known why the birds snap like that.
President Gayle Hutchinson (center) gives remarks as graduating students of the College of Behavioral and Social Sciences (BSS) that were honored during their in-person commencement ceremonies on Sunday, May 23, 2021 in Chico, Calif.
(Jason Halley/University Photographer/CSU, Chico)
Graduating students of the College of Behavioral and Social Sciences (BSS) were honored during their in-person commencement ceremonies on Saturday, May 20, 2023 in Chico, Calif.
(Matt Bates/University Photographer/Chico State)
Cotton-top Tamarin (Saguinus oedipus)
The cotton-top tamarin (Saguinus oedipus) is a small New World monkey weighing less than 0.5 kg (1.1 lb). One of the smallest primates, the cotton-top tamarin is easily recognized by the long, white sagittal crest extending from its forehead to its shoulders. The species is found in tropical forest edges and secondary forests in northwestern Colombia, where it is arboreal and diurnal. Its diet includes insects and plant exudates, and it is an important seed disperser in the tropical ecosystem.
The cotton-top tamarin displays a wide variety of social behaviors. In particular, groups form a clear dominance hierarchy where only dominant pairs breed. The female normally gives birth to twins and uses pheromones to prevent other females in the group from breeding. These tamarins have been extensively studied for their high level of cooperative care, as well as altruistic and spiteful behaviors. Communication between cotton-top tamarins is sophisticated and shows evidence of grammatical structure, a language feature that must be acquired.
Up to 40,000 cotton-top tamarins are thought to have been caught and exported for use in biomedical research before 1976, when CITES gave them the highest level of protection and all international trade was banned. Now, the species is at risk due to large-scale habitat destruction, as the lowland forest in northwestern Colombia where the cotton-top tamarin is found has been reduced to 5% of its previous area. It is currently classified as critically endangered and is one of the rarest primates in the world, with only 6,000 individuals left in the wild.
Taxonomy and naming
S. oedipus has the common names "cotton-top tamarin" and "cotton-headed tamarin" in English. Its name comes from the white hair that spans its head and flows down past the neck. In Spanish, it is commonly called bichichi, tití pielroja, "tití blanco, tití cabeza blanca, or tití leoncito. In German-speaking areas, the cotton-top tamarin is commonly known as Lisztaffe (literally "Liszt monkey") most likely due to the resemblance of its crest to the hairstyle of Hungarian composer and piano virtuoso Franz Liszt.
The species was first described by Linnaeus in 1758 as Simia oedipus. Linnaeus chose the species name oedipus, which means swollen foot, but as the species does not have particularly large feet, it is unknown why he chose this name. (Linnaeus often selected names from mythology without any particular rationale, and he may have used the name of Oedipus, the mythical Greek king of Thebes, more or less arbitrarily.) In 1977, Philip Hershkovitz performed a taxonomic analysis of the species based on fur coloration patterns, cranial and mandibular morphology, and ear size. He classified Geoffroy's tamarin S. geoffroyi as a subspecies of S. oedipus. Subsequent analyses by Hernández-Camacho and Cooper (1976), Mittermeier and Coimbra-Filho (1981), and later Grooves (2001) consider the S. oedipus and S. geoffroyi types to be separate species.
Some researchers, such as Thorington (1976), posit that S. oedipus is more closely related to the white-footed tamarin (S. leucopus) than to S. geoffroyi. This view is supported by Hanihara and Natoria's analysis of toothcomb dental morphology (1987) and by Skinner (1991), who found similarities between S. oedipus and S. leucopus in 16 of 17 morphological traits considered.
This species of white-headed tamarin is thought to have diverged from the other Amazonian forms such as S. leucopus. This is supported by morphological considerations of the transition from juvenile to adulthood, during which the fur coloration patterns change significantly and are similar between the two species. Hershkovitz proposed that the separation of the two species happened in the Pleistocene at the height of the Atrato River, where it intersected the Cauca-Magdalena. At that time, the area was covered by a sea, which created a geographic barrier that caused the species to diverge through the process of allopatric speciation. Today, the two species are principally separated by the Atrato River.
Physical characteristics
The cotton-top tamarin is part of the most diminutive family of monkeys, Callitrichidae, the marmosets and tamarins; it weighs 432 g (15.2 oz) on average. Its head–body length is 20.8–25.9 cm (8.2–10.2 in), while its tail—which is not prehensile—is slightly longer at around 33–41 cm (13–16 in).[ The species is not sexually dimorphic, the male and female are of a similar size and weight. Members of the Callitrichinae subfamily (including this species) have sharp nails (tegulae) on all digits except the big toes, which have the flat nails (ungulae) common to other primates. Tegulae resemble a squirrel's claws and help with movement through trees.
The cotton-top tamarin has a long sagittal crest, consisting of white hairs, from forehead to nape flowing over the shoulders. The skin of the face is black with gray or white bands located above the eyes. These bands continue along the edge of the face down to the jaw. Tamarins are generally divided into three groups by their facial characteristics: hairy-faced, mottled-faced, and bare-faced. The cotton-top tamarin has fine white hairs covering its face, but they are so fine as to appear naked, thus is considered a bare-faced tamarin. Its lower canine teeth are longer than its incisors, creating the appearance of tusks. Like other callitrichids, the cotton-top tamarin has two molar teeth on each side of its jaw, not three like other New World monkeys.
The cotton-top tamarin has fur covering all of the body except the palms of the hands and feet, the eyelids, the borders of the nostrils, the nipples, the anus, and the penis. The back is brown, and the underparts, arms and legs are whitish-yellow. The rump and inner thighs and upper tail are reddish-orange. The fur is distributed with varying densities throughout the body: the genital region (scrotum and pubic zone), axilla, and the base of the tail have lower densities, while the forward region is much higher. Many individuals have stripes or whorls of fur of striking coloration on their throats. The cotton-top also has whiskers on its forehead and around its mouth.
Habitat and distribution
The cotton-top tamarin is restricted to a small area of northwest Colombia, between the Cauca and Magdalena Rivers to the south and east, the Atlantic coast to the north, and the Atrato River to the west. They mostly live Brazil; two-thirds of their habitat has been destroyed. Historically, the entire area was suitable for the cotton-top tamarin, but due to habitat loss through deforestation, it survives in fragmented parks and reserves. One of the most important areas for the cotton-top is the Paramillo National Park, which consists of 460,000 hectares (1,800 sq mi) of primary and secondary forests.
The cotton-top tamarin is found in both primary and secondary forests, from humid tropical forests in the south of its range to tropical dry forests in the north. It is seldom found at altitudes above 400 m (1,300 ft), but has been encountered up to 1,500 m (4,900 ft). It prefers the lower levels of the tropical forests, but may also be found foraging on the ground and between the understory and the canopy. It can adapt to forest fragments and can survive in relatively disturbed habitats. In the dry forests are pronounced seasons. Between December and April, it is dry, while heavy rainfall occurs between August and November which can flood the forest floor. Across its range, annual rainfall varies between 500 and 1,300 mm (20 and 51 in).
Ecology
The cotton-top tamarin has a diet of mainly fruit (40%) and animal material (40%). This includes insects, plant exudates such as gum and sap, nectar, and occasionally reptiles and amphibians. Due to its small body size and high food passage rate, its diet must be high-quality and high-energy. Insectivory is common in the cotton-top and the species hunts for insects using a variety of methods: stealth, pouncing, chasing, exploring holes, and turning over leaves.
Tamarins act as seed dispersers in tropical ecosystems. While larger primates eat larger seeds, tamarins eat the smaller ones. The expelled seeds have a higher germination rate than others and ingesting larger seeds may help to dislodge and expel intestinal parasites.
The cotton-top tamarin is diurnal and sleeps with its social group in trees with foliage cover. The group leaves the sleeping tree together an hour after dawn and spends the day foraging, resting, travelling, and grooming. The species is thought to rise late and increases the speed of its foraging and travelling before dusk to avoid crepuscular and nocturnal predators. Its main predators include raptors, mustelids, felids, and snakes. The cotton-top tamarin is extremely vigilant, always looking for potential predators. When the group is resting, one individual moves apart and acts as a lookout to alert the group if it sees a threat.
The cotton-top tamarin can live as long as 24 years in captivity, while its lifespan in the wild averages 13 years.
Behavior
Social systems
The cotton-top tamarin is a highly social primate that typically lives in groups of two to nine individuals, but may reach up to 13 members. These small familial groups tend to fluctuate in size and in composition of individuals and a clear dominance hierarchy is always present within a party. At the head of the group is the breeding pair. The male and female in this pair are typically in a monogamous reproductive relationship, and together serve as the group's dominant leaders.
Dominant pairs are the only breeding pair within their groups, and the female generally has authority over the breeding male. While nonbreeding group members can be the leading pair's offspring, immigrant adults may also live with and cooperate in these groups. This social grouping in cotton-top tamarins is hypothesized to arise from predation pressure. Cotton-top tamarins exhibit prosocial behavior that benefits other members of the group, and are well known for engaging in cooperative breeding whereby the group's subordinate adults help in rearing the offspring of the dominant pair. The dominant female is more likely to give birth to nonidentical twins than a singleton, so it would be too energetically expensive for just one pair to raise the young.
To prevent younger, subordinate females within the group from breeding, the dominant female uses pheromones. This suppresses sexual behavior and delays puberty. Unrelated males that join the group can release the females from this reproductive suppression; this may result in more than one female of the group becoming pregnant, but only one of the pregnancies will be successful.
Cooperation
In cooperative breeding, the effort put into caring for the dominant breeders' offspring is shared by the group members. Parents, siblings, and immigrant adults share young rearing duties for the breeding pair's young. These duties include carrying, protecting, feeding, comforting, and even engaging in play behavior with the group's young. Cotton-top tamarins display high levels of parental investment during infant care. Males, particularly those that are paternal, show a greater involvement in caregiving than do females. Despite this, both male and female infants prefer contact and proximity to their mothers over their fathers. Males may invest additional support in rearing offspring as a form of courtship to win favor of the group's dominant female. However, evidence indicates that time spent carrying infants does not correlate with a male's overall copulation frequency.
Since only one female in a group breeds, heavy investment in infant care ensures that all offspring survive until independence. Accordingly, cotton-top tamarins bear excessive costs to care for the group's young. Male carriers, especially paternal carriers, incur large energetic costs for the sake of the group's young. This burden may cause some male cotton-tops to lose up to 10–11% of their total body weight. The large weight loss may occur from reduced food intake as infant-carrying inhibits foraging ability for a carrier. The trend of male-carrier weight loss and decreased food intake is in contrast to the dominant female's periovulatory period, when she gains weight after increasing her own food intake and relinquishing much of her infant-carrying duties.
Altruism
While caregiving by males appears to be altruistic, particularly in cotton-top sires, the costs of infant care may in fact be tolerated for selfish reasons. Namely, the costs to male weight and foraging ability may in turn promote consecutive pregnancies in dominant females, thereby providing more offspring bearing the sire's genes. Additionally, the cooperative breeding structure of cotton-tops can change with group size and parental experience. First-time sires spend a greater amount of time carrying the infant than experienced ones, and in smaller groups, sires do a greater proportion of carrying and feeding the infant than in larger groups, where helpers take on more of the work. Total care for infants remains constant with varying group size, and infant outcome is not significantly different in groups that have differing levels of experience in raising offspring.
The cooperative breeding hypothesis predicts that cotton-top tamarins engage with this young-rearing paradigm, and in turn naturally embrace patterns of prosocial behavior. These monkeys engage in such behavior by acting altruistically within their groups in caring for infants, vocalizing alarm calls, and in sharing food. Though some studies indicate that cotton-top tamarins have the psychological capacity to participate in reciprocally mediated altruism, it is unclear whether the cotton-top tamarin acts solely using judgements on reinforcement history.
Other studies involving cotton-top tamarins have hinted that positive reciprocity and reciprocal altruism are irrelevant in the prosociality of these primates.[20] Some researchers believe these primates tend to cooperate for selfish reasons and in situations where they incur some benefit for themselves. That is, cooperation in cotton-top tamarins can be better described by mutualism than by true altruism.
Tamarins in captivity have shown the ability to distinguish other individuals based on cooperative tendencies and past behavior. Cotton-tops ultimately use this information to guide future cooperation. Brief periods of defection tend to cause swift, irreparable breakups between these primates and their cooperators. To avoid this, cotton-top tamarins may make economically driven decisions based on the projected incentives of a potential cooperator.
Spite and aggression
Despite an expansive array of altruistic behaviors, cotton-top tamarins engage in great bouts of spite through negative reciprocity and punishment. They have been observed to immediately start denying cooperation with monkeys that deny them benefits. Further, in captivity, these primates are not observed to increase altruistic behavior with fellow primates that are committed fully to cooperation. Based on this, researchers believe that repeated interactions in a cooperative society like that of the cotton-top tamarin can heighten the chances that an individual will designate behavioral punishments to others in its group. This reaction has also been observed in other species. However, these reciprocal punishments, or relative lack of altruistic actions, may alternatively happen as a result of response facilitation that increases the chances of a cotton-top punishing another primate after watching that individual perform a similar action.
Another way to look at punishment in cotton-top tamarins is by observing their aggressive behavioral responses within and between groups, as well as between species. The cotton-top tamarin, like many marmosets, other tamarins, and specifically those in the genus Saguinus, stages aggressive displays almost exclusively towards fellow monkeys that belong to the same gender. These intrasexual displays of aggression are more frequent in females, and are vital when a breeding female is forcing both subadult and adult females to emigrate out of a familial group.
Though aggression can occur within groups, the response towards intruders of another species is much more drastic and can involve a sexual dimorphism in displays. Females typically employ scent-marking intruder response tactics, whereas males are more prone to vocalizing threats, physical aggression, and piloerection. Scent-marking in cotton-top tamarins is done in two ways: either using anogenital scent-marking, or suprapubic scent-marking. The ability to use both of these separate glandular fields for threat signals may indicate females have developed diverging evolutionary threats through differential use of these markings. These variable signals may be used to sign a territorial encounter, or serve as a reproductive signal. The intensity of female threats are generally comparable when directed at intruders of either genders. In contrast, male cotton-tops are considerably more threatening towards fellow males than towards females.
Communication
The cotton-top tamarin vocalizes with bird-like whistles, soft chirping sounds, high-pitched trilling, and staccato calls. Researchers describe its repertoire of 38 distinct sounds as unusually sophisticated, conforming to grammatical rules. Jayne Cleveland and Charles Snowdon performed an in-depth feature analysis to classify the cotton-top's repertoire of vocalizations in 1982. They concluded that it uses a simple grammar consisting of eight phonetic variations of short, frequency-modulated "chirps"—each representing varying messages—and five longer constant frequency "whistles". They hypothesize that some of these calls demonstrate that the cotton-top tamarin uses phonetic syntax, while other calls may be exemplars of lexical syntax usage. Each type of call is given a letter signifier; for example, C-calls are associated with finding food and D-calls are associated with eating. Further, these calls can be modified to better deliver information relevant to auditory localization in call-recipients. Using this range of vocalizations, the adults may be able to communicate with one another about intention, thought processes, and emotion, including curiosity, fear, dismay, playfulness, warnings, joy, and calls to young.
Language acquisition
Over the first 20 weeks after a cotton-top tamarin is born, it is not fully capable of producing the range of vocalizations that an adult monkey can. Despite this limitation on speech producibility, researchers believe that language acquisition occurs early on with speech comprehension abilities arising first. Infants can at times produce adult-like chirps, but this is rarely done in the correct context and remains inconsistent across the first 20 weeks of life. Regardless, infant cotton-tops are able to respond in behaviorally appropriate ways to varying contexts when presented with adult chirps. This indicates that verbal perception is a quickly acquired skill for offspring, followed closely by auditory comprehension, and later by proper vocal producibility.
Castro and Snowdon (2000) observed that aside from inconsistent adult-like chirping, cotton-top infants most often produce a prototype chirp that differs in vocalization structure from anything seen in the full adult range of vocalizations. Infants are thought to imitate adult speakers, which use differing calls in various contexts, but by using solely the infant prototypical chirp. For instance, adult cotton-tops are known to significantly reduce the amount of general alarm calling in the presence of infants. This is likely adapted so that adults in close proximity to the group's young do not attract attention of predators to infant-dense areas. Additionally, infants reduce their prototype chirping in the presence of predators. Whether infants are shadowing the calling behavior of adults or they are comprehending danger remains unclear. However, researchers argue that young cotton-top tamarins are able to represent semantic information regardless of immature speech production.
To confirm the notion that language acquisition occurs as a progression of comprehension before production, Castro and Snowdon (2000) showed that infants respond behaviorally to vocalizing adults in a fashion that indicates they can comprehend auditory inputs. When an adult produces a C-call chirp, used to indicate food preference and when navigating to a food source, an infant approaches the adult caller to be fed, but do not use the prototype calling as a proxy for C-calls. This finding argues for the idea that infants are able to understand vocalizations first, and later acquire the ability to communicate with adult vocalizations.
General calling
Among the typical cotton-top tamarin communicative vocalizations, the combination long call (CLC) and the alarm call (AC) are the most heavily represented in the literature. CLCs encompass a range of contact calls that are produced by isolated individuals using chirps and whistles. This type of call is also used for seemingly altruistic alarm calls, thus adding to its range of cooperative behaviors. It is issued in the presence of kin when a threatening llamas predator is seen. Predators of the cotton-top tamarin include snakes, ocelots, tayras, and most notably, hawks. Early observations by Patricia Neyman even showed that cotton-tops produce diverse sets of alarm calls that can discriminate the presence of birds of prey versus ground-based predators.
CLCs involve the production of complex sequence multisyllabic vocalizations. Researchers have argued that long calls exhibit individual differences, thus can carry information sufficient for recipients to determine caller identity. Using habituation-discrimination paradigms in language experiments, this theory has been confirmed multiple times in literature. However, the individual syllables within a complete CLC vocalization in isolation of each other do not transfer sufficient information to communicate messages between monkeys. Scientists thus consider the whole, intact string of vocalizations to be the unit of perception for CLCs in the cotton-top tamarin. These examinations may confirm that cotton-tops incorporate a lexical syntax in areas of their communication.
Since tamarins can discriminate between predatory threats using varying vocalizations, recipients of an AC are thought to extract various complex signals from this form of communication. Primarily, cotton-tops are able to glean the identity of the cooperating tamarin through differences in individuals' alarm calls. Further, adults are able to discriminate the gender of callers from their ACs and determine the range of calls within a related tamarin's alarm calling repertoire. Alarm call-based identification is postulated to play a number of functional roles in the cotton-top tamarin. Firstly, an AC recipient is able to identify a cooperating tamarin, and by recognizing which in their group it is, be able to judge the reliability of the AC from past experience. This may arise from a selective pressure for being able to statistically determine the amount of risk present, and how endangered an individual and its group are.
Additionally, being able to localize auditory signals may help determine predator location, especially in the presence of a second AC from a different tamarin in the group. This can help confirm predator presence, type (e.g. flying versus ground-based), and support the recipient in triangulating a predator's location. In the context of the cotton-top's cooperative breeding groups, this is postulated as being adaptive for determining the variable risk to one's group members. For example, a call recipient is able to determine which of its kin are and are not at risk (e.g. young offspring, mates, subordinates, relatives, carriers, etc.) and plan subsequent actions accordingly.
Food calls
The cotton-top tamarin makes selective, specialized vocalizations in the presence of food. These include the C-call, produced when a cotton-top approaches and sorts through food, and the D-call, which is associated with food retrieval and is exhibited while eating.
C-call chirping is believed to be an honest signal for communicating food preference, and a cotton-top tamarin more often and more rapidly vocalizes with these chirps when approaching a highly favored food source. Functionally, this behavior may inform other tamarins of the actions the caller will take in a feeding context and whether a preferable food source is available. Despite this research indicating that food calls may be informative to fellow group mates, other observations of cotton-tops show that quantity and distribution of food and audience do not significantly alter a caller's food-centered vocalizations.
The cotton-top tamarin is seen to produce food calls both in the presence and absence of group members. Additionally, response to food calls are directed back to an original caller independent of visual confirmation of a food source. While this may appear to be a result from a very primitive form of communication, Roush and Snowdon (2005) maintain that the food-calling behavior confers some mentally representable information about food to recipient tamarins.
Conservation status
The wild population is estimated at 6,000 individuals, with 2,000 adults. This species is critically endangered, and was listed in "The World's 25 Most Endangered Primates between 2008 and 2012." The publication lists highly endangered primate species and is released every two years by the International Union for Conservation of Nature Species Survival Commission Primate Specialist Group. The cotton-top tamarin was not selected for the 2012–2014 publication.
Habitat destruction through forest clearing is the main cause of this collapse, and the cotton-top has lost more than three-quarters of its original habitat to deforestation, while the lowland forest in which it lives has been reduced to 5% of its historical range. This land is then used for large-scale agricultural production (i.e. cattle) and farming, logging, oil palm plantations, and hydroelectric projects that fragment the cotton-top tamarin's natural range.
The illegal pet trade and scientific research have also been cited as factors by the IUCN. While biomedical studies have recently limited their use of this species, illegal capture for the pet trade still plays a major role in endangering the cotton-top. Before 1976, when CITES listed the species under Appendix I banning all international trade, the cotton-top tamarin was exported for use in biomedical research.
In captivity, the cotton-top is highly prone to colitis, which is linked to an increased risk of a certain type of colon cancer. Up to 40,000 individuals were caught and exported for research into those diseases, as well as Epstein-Barr virus, for the benefit of humans. The species is now protected by international law. Although enough individuals are in captivity to sustain the species, it is still critically endangered in the wild.
The Proyecto Tití ("Project Tamarin") was started in 1985 to provide information and support in conservation of the cotton-top tamarin and its habitat in northern Colombia. Proyecto Tití's programs combine field research, education, and community programs to spread awareness about this endangered species and encourage the public to participate in its protection. It now has partner status with the Wildlife Conservation Network.
In January 2015, two captive cotton-top tamarins at the Alexandria Zoological Park in Alexandria, Louisiana, died when a caretaker left them outside overnight in temperatures as low as 30 °F. One other individual survived.
[Credit: en.wikipedia.org]
The Eisenhower Leader Development Program graduated its 14th Cohort at the U.S. Military Academy’s Thayer Award Room, May 17. The 24 graduates participated in the year-long master’s degree program, jointly administered by USMA’s Department of Behavioral Sciences and Leadership and Columbia University’s Teachers College. (U.S. Army photo by Matthew Moeller)
NORTH HOLLYWOOD - More that 50 Los Angeles Firefighters rotated through duty assignments over a five hour period, while assisting law enforcement and utility officials in safely managing a one patient behavioral emergency on June 14, 2013. © Photo by Mike Meadows
Hat - Ardenne Montreal
Top - Thrifted - Renaissance -
Skirt - Thrifted
Shoes - Thrifted - Village des Valeurs
"Today, I'm a tiger". Child playing make-believe. Extras from child behavioral series (see below).
(file #: in-your-face-intense_0925c)
The spiketail dragonflies (cordulegastridae) are named for the prominent ovipositor of the females which they use to deposit eggs in streambanks with what has been described as a sewing-machine like motion. In this video, just to the left of the red flag is a female spiketail— most likely an arrowhead spiketail based on the fact that I know them to be in this general area— ovipositing in the stream bank. This was something I wanted to see and video and was blessed to have this impromptu opportunity while volunteering for a Riverwatch Macroinvertebrate Survey.