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This little birdy (I named it Mohawk) fell out of its nest whilst still in it's egg. Sadly, it didn't not survive... Its fragile shell cracked on impact on my balcony floor. It was long dead once I found it.
A tortoise embryo at the Galapagos Giant Tortoise Centre on Isabella
Galapagos Giant Tortoise
The Galápagos tortoise or Galápagos giant tortoise (Geochelone nigra) is the largest living tortoise, native to seven islands of the Galápagos archipelago. The Galápagos tortoise is unique to the Galápagos Islands. Fully grown adults can weigh over 300 kilograms (661 lb) and measure 1.2 meters (4 ft) long. They are long-lived with a life expectancy in the wild estimated to be 100-150 years. Populations fell dramatically because of hunting and the introduction of predators and grazers by humans since the seventeenth century. Now only ten subspecies of the original twelve exist in the wild. However, conservation efforts since the establishment of the Galápagos National Park and the Charles Darwin Foundation have met with success, and hundreds of captive-bred juveniles have been released back onto their home islands. They have become one of the most symbolic animals of the fauna of the Galápagos Islands. The tortoises have very large shells (carapace) made of bone. The bony plates of the shell are integral to the skeleton, fused with the ribs in a rigid protective structure. Naturalist Charles Darwin remarked "These animals grow to an immense size ... several so large that it required six or eight men to lift them from the ground.". This is due to the phenomenon of island gigantism whereby in the absence of natural predation, the largest tortoises had a survival advantage and no disadvantage in fleeing or fending off predators. When threatened, it can withdraw its head, neck and all forelimbs into its shell for protection, presenting a protected shield to a would-be predator. The legs have hard scales that also provide armour when withdrawn. Tortoises keep a characteristic scute pattern on their shell throughout life. These have annual growth bands but are not useful for aging as the outer layers are worn off. There is little variation in the dull-brown colour of the shell or scales. Physical features (including shape of the shell) relate to the habitat of each of the subspecies. These differences were noted by Captain Porter even before Charles Darwin. Larger islands with more wet highlands such as Santa Cruz and the Alcedo Volcano on Isabela have lush vegetation near the ground. Tortoises here tend to have 'dome-back' shells. These animals have restricted upward head movement due to shorter necks, and also have shorter limbs. These are the heaviest and largest of the subspecies.Smaller, drier islands such as Española and Pinta are inhabited by tortoises with 'saddleback' shells comprising a flatter carapace which is elevated above the neck and flared above the hind feet. Along with longer neck and limbs, this allows them to browse taller vegetation. On these drier islands the Galápagos Opuntia cactus (a major source of their fluids) has evolved a taller, tree-like form. This is evidence of an evolutionary arms race between progressively taller tortoises and correspondingly taller cacti. Saddlebacks are smaller in size than domebacks. They tend to have a yellowish color on lower mandible and throat. At one extreme, the Sierra Negra volcano population that inhabits southern Isabela Island has a very flattened "tabletop" shell. However, there is no saddleback/domeback dualism; tortoises can also be of 'intermediate' type with characteristics of both. The tortoises are slow-moving reptiles with an average long-distance walking speed of 0.3 km/h (0.18 mph). Although feeding giant tortoises browse with no apparent direction, when moving to water-holes or nesting grounds, they can move at surprising speeds for their size. Marked individuals have been reported to have traveled 13 km in two days. Being cold-blooded, the tortoises bask for two hours after dawn, absorbing the energy through their shells, then becoming active for 8–9 hours a day. They may sleep for about sixteen hours in a mud wallow partially or submerged in rain-formed pools (sometimes dew ponds formed by garua-moisture dripping off trees). This may be both a thermoregulatory response and a protection from parasites such as mosquitoes and ticks. Some rest in a 'pallet'- a snug depression in soft ground or dense brush- which probably helps to conserve heat and may aid digestion. On the Alcedo Volcano, repeated use of the same sites by the large resident population has resulted in the formation of small sandy pits. Darwin observed that: "The inhabitants believe that these animals are absolutely deaf; certainly they do not overhear a person walking near behind them. I was always amused, when overtaking one of these great monsters as it was quietly pacing along, to see how suddenly, the instant I passed, it would draw in its head and legs, and uttering a deep hiss fall to the ground with a heavy sound, as if struck dead." The tortoises can vocalise in aggressive encounters, whilst righting themselves if turned upside down and, in males, during mating. The latter is described as "rhythmic groans". The tortoises are herbivorous animals with a diet comprising cactus, grasses, leaves, vines, and fruit. Fresh young grass is a favorite food of the tortoises, and others are the 'poison apple' (Hippomane mancinella) (toxic to humans), the endemic guava (Psidium galapageium), the water fern (Azolla microphylla), and the bromeliad (Tillandsia insularis). Tortoises eat a large quantity of food when it is available at the expense of incomplete digestion. Its favorite food is grasses. The tortoise normally eat an average of 70 to 80 pounds a day. Tortoises have a classic example of a mutualistic symbiotic relationship with some species of Galápagos finch. The finch hops in front of the tortoise to show that it is ready and the tortoise then raises itself up high on its legs and stretches out its neck so that the bird can pick off ticks that are hidden in the folds of the skin (especially on the rear legs, cloacal opening, neck, and skin between plastron and carapace), thus freeing the tortoise from harmful parasites and providing the finch with an easy meal. Other birds, including Galápagos Hawk and flycatchers, use tortoises as observation posts from which to sight their prey. Mating occurs at any time of the year, although it does have seasonal peaks between January and August. When two mature males meet in the mating season they will face each other, rise up on their legs and stretch up their necks with their mouths open to assess dominance. Occasionally, head-biting occurs, but usually the shorter loser tortoise will back off, leaving the other to mate with the female. In groups of tortoises from mixed island populations, saddleback males have an advantage over domebacks. Frustrated non-dominant males have been observed attempting to mate with other males and boulders. The male sniffs the air when seeking a female, bellows loudly, and bobs his head. The male then rams the female with the front of his shell and bites her exposed legs until she withdraws them, immobilizing her. Copulation can last several hours with roaring vocalisations from the males. Their concave shell base allows males to mount the females from behind. It brings its tail which houses the penis into the female's cloaca. After mating (June-December), the females journey up to several kilometres to reach nesting areas of dry, sandy ground (often near the coast). Nest digging can last from hours to days and is elaborate and exhausting. It is carried out blindly using only the hind legs to dig a 30 cm deep hole, into which she lays up to sixteen hard-shelled eggs the size of tennis balls. The female makes a muddy plug for the nest hole out of soil mixed with urine and leaves the eggs to incubate. In rocky areas, the eggs are deposited randomly into cracks. The young emerge from the nest after 120 to 140 days gestation later (December-April) and may weigh only 80 grams (2.8 oz) and measure 6 centimetres (2.4 in). Temperature plays a role in the sex of the hatchling: if the nest temperature is lower, more males will hatch; if it is high, more females will hatch. When the young tortoises emerge from their shells, they must dig their way to the surface, which can take up to a month. All have domed carapaces, and subspecies are indistinguishable. Galápagos Hawk used to be the only native predator of the tortoise hatchlings, as Darwin remarked: "The young tortoises, as soon as they are hatched, fall prey in great numbers to buzzards". Sex can be determined only when the tortoise is 15 years old, and sexual maturity is reached at 20 to 25 years old. The tortoises grow slowly for about 40 years until they reach their full size. Reproductive prime is considered to be from the ages of 60–90. The shape of the carapace of some subspecies of the tortoises is said to have reminded the early Spanish explorers of a kind of saddle they called a "galápago," and for these saddle-shaped tortoises they named the archipelago. Up to 250,000 tortoises inhabited the islands when they were discovered. Today only about 15,000 are left.
The inhabitants...state that they can distinguish the tortoise from different islands; and that they differ not only in size, but in other characters. Captain Porter has described those from Charles and from the nearest island to it, namely Hood Island, as having their shells in front thick and turned up like a Spanish saddle, whilst the tortoises from James Island are rounder, blacker, and have a better taste when cooked.---Charles Darwin 1845
There were probably twelve subspecies of Geochelone nigra in the Galápagos Islands, although some recognise up to 15 subspecies. Now only 11 subspecies remain, five on Isabela Island, and the other six on Santiago, Santa Cruz, San Cristóbal, Pinzón, Española and Pinta. Of these, the Pinta Island subspecies is extinct in the wild and is represented by a single individual (Lonesome George). In the past, zoos took animals without knowing their island of origin. Production of fertile offspring from various pairings of tortoises largely confirmed that they are subspecies and not different species. All the subspecies of giant tortoise evolved in Galápagos from a common ancestor that arrived from the mainland, floating on the ocean currents (the tortoises can drift for long periods of time as they are buoyant and can stretch head upwards to breathe). Only a single pregnant female or breeding pair needed to arrive in this way, and then survive, for Galápagos to be colonised. In the seventeenth century, pirates started to use the Galápagos islands as a base for resupply, restocking on food, water and repairing vessels before attacking Spanish colonies on the South American mainland. The tortoises were collected and stored live on board ships where they could survive for at least a year without food or water, providing valuable fresh meat, whilst their diluted urine and water stored in their neck bags could also be used as drinking water. Of the meat, Darwin wrote: "the breast-plate roasted (as the Gauchos do 'carne con cuero'), with the flesh on it, is very good; and the young tortoises make excellent soup; but otherwise the meat to my taste is indifferent." In the nineteenth century, whaling ships and fur-sealers collected tortoises for food and many more were killed for high grade 'turtle oil' from the late 1800s onward. Darwin described this process thus: "beautifully clear oil is prepared from the fat. When a tortoise is caught, the man makes a slit in the skin near its tail, so as to see inside its body, whether the fat under the dorsal plate is thick. If it is not, the animal is liberated and it is said to recover soon from this strange operation." A total of over 15,000 tortoises is recorded in the logs of 105 whaling ships between 1811 and 1844. As hunters found it easiest to collect the tortoises living round the coastal zones, the least decimated populations tended to be those in the highlands. Population decline accelerated with the early settlement of the islands, when they were hunted for meat, their habitat was cleared for agriculture and alien mammal species were introduced. Feral pigs, dogs, cats and black rats are effective predators of eggs and young tortoises, whilst goats, donkeys and cattle compete for grazing. In the twentieth century, increasing human settlement and urbanisation and collection of tortoises for zoo and museum specimens depleted numbers even more. The Galápagos giant tortoise is now strictly protected. Young tortoises are raised in a programme by the Charles Darwin Research Station in order to bolster the numbers of the extant subspecies. Eggs are collected from places on the islands where they are threatened and when the tortoises hatch they are kept in captivity until they have reached a size that ensures a good chance of survival and are returned to their original ranges. The Galápagos National Park Service systematically culls feral predators and competitors where necessary such as the complete eradication of goats from Pinta. The conservation project begun in the 1970s successfully brought 10 of the 11 endangered subspecies up to guarded population levels. The most significant recovery was that of the Española Tortoise, whose breeding stock comprised 2 males and 11 females brought to the Darwin Station. Fortuitously, a third male was discovered at the San Diego Zoo and joined the others in a captive breeding program. These 13 tortoises gave rise to over 1000 tortoises now released into their home island. In all, 2500 individuals of all breeds have been reintroduced to the islands. However, persecution still continues on a much smaller scale; more than 120 tortoises have been killed by poachers since 1990 and they have been taken hostage as political leverage by local fishermen.
Isabella
Shaped like a sea horse, Isabela is the largest of the the islands in the Galapagos, more than 4 times larger than Santa Cruz the next largest. Isabela is 80 miles (100 km) in length and though it is remarkably beautiful it is not one of the most visited islands in the chain. Its visitor sites are far apart making them accessible only to faster boats or those with longer itineraries. One of the youngest islands, Isabela is located on the western edge of the archipelago near the Galapagos hot spot. At approximately 1 million years old, the island was formed by the merger of 6 shield volcanoes - Alcedo, Cerro Azul, Darwin, Ecuador, Sierra Negra and Wolf. Five of the six volcanoes are still active (the exception is Ecuador) making it one of the most volcanically active places on earth. Visitors cruising past Elizabeth Bay on the west coast can see evidence of this activity in the fumaroles rising from Volcan Chico on Sierra Negra. Two of Isabela's volcanoes lie directly on the equator - Ecuador and Volcan Wolf. Volcan Wolf is the youngest of Isabela's volcanoes and at 5,600ft (1707 m) the highest point in the Galapagos. Isabela is known for its geology, providing visitors with excellent examples of the geologic occurrences that have created the Galapagos Islands including uplifts at Urbina Bay and the Bolivar Channel, Tuft cones at Tagus Cove, and Pulmace on Alcedo. Isabela is also interesting for its flora and fauna. The young island does not follow the vegetation zones of the other islands. The relatively new lava fields and surrounding soils have not developed the sufficient nutrients required to support the varied life zones found on other islands. Another obvious difference occurs on Volcan Wolf and Cerro Azul, these volcanoes loft above the cloud cover and are arid on top. Isabela's rich animal, bird, and marine life is beyond compare. Isabela is home to more wild tortoises than all the other islands. Isabela's large size and notable topography created barriers for the slow moving tortoises; apparently the creatures were unable to cross lava flows and other obstacles, causing several different sub-species of tortoise to develop. Today tortoises roam free in the calderas of Alcedo, Wolf, Cerro Azul, Darwin and Sierra Negra. Alcedo Tortoises spend most of their life wallowing in the mud at the volcano crater. The mud offers moisture, insulation and protects their exposed flesh from mosquitoes, ticks and other insects. The giant tortoises have a mediocre heat control system requiring them to seek the coolness of the mud during the heat of the day and the extra insulation during the cool of the night. On the west coast of Isabela the nutrient rich Cromwell Current upwelling creating a feeding ground for fish, whales, dolphin and birds. These waters have long been known as the best place to see whales in the Galapagos. Some 16 species of whales have been identified in the area including humpbacks, sperms, sei, minkes and orcas. During the 19th century whalers hunted in these waters until the giant creatures were near extinction. The steep cliffs of Tagus Cove bare the names of many of the whaling ships and whalers which hunted in these waters. Birders will be delighted with the offerings of Isabela. Galapagos Penguins and flightless cormorants also feed from the Cromwell Current upwelling. These endemic birds nest along the coast of Isabela and neighboring Fernandina. The mangrove finch, Galapagos Hawk, brown pelican, pink flamingo and blue heron are among the birds who make their home on Isabela. A colorful part to any tour located on the western shore of Isabela, Punta Moreno is often the first or last stopping point on the island (depending on the direction the boat is heading). Punta Moreno is a place where the forces of the Galapagos have joined to create a work of art. The tour starts with a panga ride along the beautiful rocky shores where Galapagos penguins and shore birds are frequently seen. After a dry landing the path traverses through jagged black lava rock. As the swirling black lava flow gave way to form craters, crystal tide pools formed-some surrounded by mangroves. This is a magnet for small blue lagoons, pink flamingos, blue herons, and Bahama pintail ducks. Brown pelican can be seen nesting in the green leaves of the mangroves. You can walk to the edge of the lava to look straight down on these pools including the occasional green sea turtle, white-tipped shark and puffer fish. This idyllic setting has suffered from the presence of introduced species. Feral dogs in the area are known to attack sea Lions and marine iguanas.
Galapagos Islands
The Galápagos Islands (official name: Archipiélago de Colón; other Spanish names: Islas de Colón or Islas Galápagos) are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, some 900 km west of Ecuador. It is a UNESCO World Heritage site: wildlife is its most notable feature. Because of the only very recent arrival of man the majority of the wildlife has no fear of humans and will allow visitors to walk right up them, often having to step over Iguanas or Sea Lions.The Galápagos islands and its surrounding waters are part of a province, a national park, and a biological marine reserve. The principal language on the islands is Spanish. The islands have a population of around 40,000, which is a 40-fold expansion in 50 years. The islands are geologically young and famed for their vast number of endemic species, which were studied by Charles Darwin during the voyage of the Beagle. His observations and collections contributed to the inception of Darwin's theory of evolution by natural selection.
Human embryos treated with aniseed oil to achieve transparency and reveal the underlying structure
From series James G. Mundie's Cabinet of Curiosities
[Copyright © 2008 James G. Mundie. Image may not be reproduced in any form without express written permission.]
These embryos are 6 days old. They are at Gosner stage 35 and 36, just after tailbud development. You can see patches of melanophores developing on the right hand embryo, and the gill rachises are clearly visible.
First captive breeding in the US of this species.
June 13th 2013.
July 9, 2020
We found a small mass of squid eggs on the beach today. In these pics, if you look closely you can see the shapes of tiny baby squid. There are no tentacles, but you can see eyes, fins and a big yolk sac.
I'm guessing they are longfin squid, (Doryteuthis pealeii), because they are around here. Please let me know if you think it's something else.
Crosby Landing Beach
Brewster, Massachusetts
Cape Cod - USA
Photo by brucetopher
© Bruce Christopher 2020
All Rights Reserved
...always learning - critiques welcome.
Tools: Canon 7D & iPhone 11.
No use without permission.
Please email for usage info.
This photo shows the early development of a Pallid Sturgeon. For more information on how researchers at the Bozeman Fish Technology Center are pitching in on the conservation efforts for this endangered species click on the link below.
www.fws.gov/bozemanfishtech/rp_conservationphysiology.html
Photo Credit: Molly Webb / USFWS
Image by Kira Heikes. Hypsibius exemplaris embryo. For imaging method, see the McGreevy et al 2018 protocol here: cshprotocols.cshlp.org/content/2018/11.toc
cross section: Zea may embryo
common name: corn grain
magnification: 40x
Triarch quadruple stain
Berkshire Community College Bioscience Image Library
Technical Questions:bioimagesoer@gmail.com
A three day old chicken embryo photographed using a customized stereo microscope. The embryo will help researchers learn about congenital heart defects.
This image is a 2015 FASEB BioArt winner and was featured on the NIH Director's blog: directorsblog.nih.gov/2016/02/25/snapshots-of-life-green-...
Credit: Jessica Ryvlin, Stephanie Lindsey, and Jonathan Butcher, Cornell University, Ithaca, NY
This image is not owned by the NIH. It is shared with the public under license. If you have a question about using or reproducing this image, please contact the creator listed in the credits. All rights to the work remain with the original creator.
NIH funding from: National Heart, Lung, and Blood Institute (NHLBI)
Kodak Brownie Hawkeye, Flip Lens
Image ©Philip Krayna, BoxxCarr, all rights reserved. This image is not in the public domain. Please contact me for permission to download, license, reproduce, or otherwise use this image, or to just say "hello". I value your input and comments. See more at www.boxxcarr.com.
Very lucky section through a perfectly preserved human embryo in an intact tubal pregnancy. This is by far the most primitive embryo I have ever seen.
I think this is at about the same developmental stage as the Hertig-Rock embryo of 1945, which has been variously estimated at 16.5 or 19 days postovulation (4 to 5 weeks by conventional obstetrical dating, counting from the first day of the last menstrual period).
cross section: Zea may embryo
common name: corn grain
magnification: 100x
Triarch quadruple stain
Berkshire Community College Bioscience Image Library
Technical Questions:bioimagesoer@gmail.com
This is really a very un-Rivlike pose, which rather amuses me. If you visit Embryo, you'll receive this umbrella as a gift, with the winsome pose in it, to protect you from the gentle rain, and I gamely put it on in Rivform. Really, the sim is quite beautiful and atmospheric. It's just not suited to Riv's dark strength. But put on something flow-y and glow-y and visit: slurl.com/secondlife/embryo/226/28/21.
I wanted to apologise to all for my lack of comments & replies (and new images!) - this is why - for those of you that know (or have seen my candle shot) will understand that this new life is extremely precious.. I've been pregnant 8 times now and this is the only one (other than Finn) that has made it to 12 weeks... Here's to another 6 months!! :))
I'll confess now, I bubbled alittle on hearing the heart beat..
cross section: Zea may embryo
common name: corn grain
magnification: 40x
Triarch quadruple stain
Berkshire Community College Bioscience Image Library
Technical Questions:bioimagesoer@gmail.com