These amazing turtles. Ancient turtles Ancient turtles

Several different families of freshwater probably tried to explore the sea. aquatic turtles. Some people succeeded. In the middle Jurassic period The first freshwater turtles appeared. All older turtles were apparently terrestrial. At the end of the Jurassic period, some freshwater turtles made an attempt to go to sea. At first they inhabited coastal zone, their limbs have not yet transformed into flippers. The first group of coastal sea turtles (Plesiochelyoidea) became extinct early Cretaceous period. Around the same time, real sea turtles with flippers appeared - protostegids (Protostegidae). They lived until the end of the Cretaceous period and went extinct along with the dinosaurs.

Protostegids were the only sea turtles throughout almost the entire Cretaceous period. Representatives of other groups that have survived to this day (Cheloniidae, Dermochelyidae) appeared 40–50 million years later. At this point, protostegids were dominant and cosmopolitan, while cheloniids and dermocheliids were probably restricted to coastal areas or inland seas. Apparently, they went to sea independently of the protostegids and were the third or even fourth attempt at the development of the seas by turtles.

The evolution of protostegids lasted tens of millions of years, during which they populated the seas of Europe, the USA, and Russia. These turtles chose a fairly common environmental strategy; Over time, they increased in size and became gigantic in order to feel safe. It was the protostegids that gave birth to the most gigantic turtle in the entire history of the Earth - the famous Archelon. In many books there is an old photograph of the skeleton of this turtle, where a man is standing next to it. In fact, the photo is a little confusing: the man in the photo, paleontologist George Wieland, was very short. Archelon was not as gigantic as you might think when looking at the photo. But still its size is colossal: the span of its front flippers was four and a half meters.

The most ancient representative of protostegids is considered to be a reptile from the Early Cretaceous, Barremian-Aptian deposits of Colombia - a large turtle Desmatochelys padillai with a skull about 30 cm long and a meter-long shell. The skull of another ancient protostegid was found by fossil collectors about ten years ago in the Ulyanovsk region. They say she had a beak “like a parrot.” The skull was sent to Moscow for study, but it has not yet been described. According to senior researcher I.G. Danilov, the skull, judging by the photographs, also belonged to a turtle of the type Desmatochelys.

Based on materials from Russia, only one species of Mesozoic sea turtle has been described so far. The history of its study is curious. In the mid-eighties, biology students from Leningrad State University went on summer practice to the Forest on Vorskla nature reserve in Belgorod region, where they studied the forest ecosystem, collected herbariums and insects. The leader L.A. Nesov decided to combine business with pleasure and took them out for additional paleontological practice. Not far from the reserve are the Lebedinsky and Stoilensky quarries, where iron ore is mined, simultaneously revealing layers of sandstones of Cretaceous age (Albian-Cenomanian), and the sandstones are rich in the remains of marine animals. The students were lucky to find several interesting specimens, including the country's first protostegid bones: a piece of lower jaw and plastron bone with the characteristic stellate shape of protostegiids. Nessov described the remains as the new kind- Russian teguliskaf ( Teguliscapha rossica). It was an early representative of protostegids, still small: about half a meter in length. Her description was published in the non-trivial collection “ Comprehensive Research biogeocenoses of forest-steppe oak forests" in 1986. As a result, the publication went unnoticed and fell out of sight of most paleontologists for thirty years.

Then the finds stopped, and only recently in Russia it was possible to find new remains of sea - and already giant - turtles from the end of the Cretaceous period. The most important discoveries were made in the spring and autumn of 2017. Excavations took place in the steppe gullies on the border of Saratov and Volgograd regions, in the “beach deposits” of the Cretaceous period (see picture of the day Mosasaurs of the Volga region). Almost the whole day taken as work force students of the Saratov State Technical University dug in vain. There were no finds, although inexperienced excavators mistook each sandstone nodule for dinosaur bones. Finally, one young man successfully dug into the sand with a shovel and turned out a stone the size of a zucchini. At first it was mistaken for sandstone, but the stone successfully split in the middle, and the spongy structure of a reddish bone appeared on the chip. The find turned out to be half of a turtle's humerus. An hour later, another student dug up an unusual shovel. Both bones were soon identified. They belonged to protostegids, although indeterminate to genus. Their more accurate systematic position currently being confirmed.

That same summer, several more turtle bones were found in the rafters. One plate of the shell showed bite marks: someone tried to eat the turtle, and possibly successfully.

Saratov protostegids were of very respectable size. From the tip of the nose to the tip of the tail, their length exceeded two meters. There are no traces of horny grooves (scutes) on the bone plates - apparently, the shells of the Volga protostegids were already covered with soft skin, although, perhaps, the traces were simply not imprinted.

It is difficult to judge the diet of extinct turtles. Most turtles have no teeth, and their jaws are covered with horny sheaths. Unfortunately, horny sheaths are not preserved in the geological record, and bone structures only partially reflect their structure. Protostegids probably ate like modern sea turtles and occupied a rather unusual ecological niche. Modern sea turtles eat anything except fish because they cannot catch it: their heads are too large and their necks are too slow. Unlike sea turtles, freshwater turtles are omnivores, and some are specialized specifically for fishing. Modern sea turtles feed on algae and shellfish. The leatherback turtle preys on clumsy jellyfish. Protostegids probably fed mainly on molluscs - ammonites and oysters.

However, among the extinct sea turtles there were also extremely unusual shapes. For example, ocepechelone ( Ocepechelon) from Late Cretaceous deposits (Maastrichtian) of Morocco. She has a gigantic skull - 70 centimeters in length. Apart from the skull, nothing survived. The upper jaw of the turtle (the lower jaw was not found) forms a massive tube about 6 centimeters in diameter. The turtle probably sucked in fry and krill through it. Perhaps it was “vacuuming” prey in dense thickets of algae or among corals. Judging by the skull, she had strong jaw muscles to create a powerful suction thrust.

The locomotion of ancient turtles is also judged mainly by analogy with modern ones, which swim using the “underwater flight” technique: with their front flippers they write “eights”, like owls, and their back flippers are used as a rudder. Perhaps protostegids also swam this way. It is possible to calculate and clarify the biomechanics, since complete skeletons of protostegids are known, but no one has done this yet.

Saratov protostegids turned out to be close to American sea turtles and became another confirmation of the hypothesis that extinct reptiles of the Mesozoic, like modern cetaceans, easily crossed the spaces of the World Ocean. Similar genera spread throughout the planet, and the species diversity of sea turtles was generally low.

Illustration © Andrey Atuchin.

Anton Nelikhov

Ancient turtles
About 200 million years ago, during the Triassic period, the ancestors of modern turtles lived on Earth side by side with dinosaurs. Turtle species Triassochelys, which lived during this period, was indeed similar to modern turtles, it grew to at least 90 cm, but unlike our turtles it had teeth. Later, 70 million years ago, in the seas of the Cretaceous period there were giant turtles, larger than any of the modern ones, which reached a length of 3.3 m, and their diameter at the widest point was 3.6 m!

The oldest turtle

was discovered in northeastern Brazil. The twenty-centimeter sea turtle lived about 110 million years ago - ten million years older than all previously known representatives of this group.

Common with birds, although closer to crocodiles

Turtles have some things in common with birds, but in the reptile group they are closer to crocodiles than to snakes or lizards. Their jaws are devoid of teeth, although some species of turtles are voracious predators and they lay eggs like birds, but their shells contain less calcium than the shells of bird eggs.

Two hundred varieties

Today among turtles there are two hundred species that are common in warm regions planets.

Fast and slow

Freshwater turtles move quickly and agilely both in the water and on land. Marines look clumsy on land, but in water their movements can be compared in beauty and ease to the flight of birds. Only slow land species. Land turtles move actively only when there is sufficient high temperature when the processes in their body proceed at normal speed.

But on the Fiji islands, the turtle is considered a symbol of speed and superior navigational abilities. She is depicted on the official letterhead of the Marine Department. Only these are not land turtles, but sea turtles. These include Ridley (Lepidochelys).

Able to hold their breath underwater for up to 10 hours

Sea turtles can hold their breath underwater for up to 10 hours and 14 minutes. This absolute record among the vertebrates existing on Earth. The previous achievement, also established by sea turtles, was much more modest - 7 hours 25 minutes. This conclusion was reached as a result of a painstaking study carried out over five years. During this period, scientists established observations in the waters Mediterranean Sea for the behavior of 10 green and 10 loggerhead turtles.

Excellent hearing, vision and smell

Charles Darwin, who claimed that turtles were deaf, was wrong. Recent electrophysiological studies of turtle hearing have shown that they have excellent hearing, especially low-pitched sounds. Aquatic turtles have hearing almost as sensitive as cats. There are stories of sea turtles emerging from the water to sing for a long time.

Turtles have good sharp vision (at least at close range) and perceive almost the entire spectrum of colors (including what we see, and even more). They respond well to bright colors - white, red, yellow. But they do not pay any attention to blue, cyan and violet tones.

In turtles, the sense of smell plays an important role; with its help, turtles not only find food, but also communicate with relatives, and even navigate the territory.

Rely on smell and hearing

Aquatic reptiles (crocodiles, alligators, turtles) rely heavily on senses such as smell and hearing to track prey, find a mate, or detect the approach of an enemy. Their vision plays an auxiliary role and operates only at close range, visual images are blurry, and they lack the ability to focus on stationary objects for a long time.

Smart turtles

Scientists conducted an experiment: they placed a feeder in front of different animals, and then moved it along a special rail and suddenly lowered the screen. The animals had to figure out where the food had gone. Not everyone succeeded. The pigeons and voles couldn't cope. The rabbits, deprived of food, jumped without knowing where. The chickens were looking for the grains they had just pecked where they had disappeared. The ducks, looking for food, tried to get to it through the wooden partition, not realizing that this was impossible. But the turtles walked along the screen, went behind it and calmly continued their breakfast.

turtle shell

The shell, which covers the entire body of the turtle with the exception of the head, paws and tail, distinguishes it from all vertebrates. Top part The shell, called a shield or carapace, is usually domed in land turtles and flatter in turtles that live primarily in water, to reduce water pressure. The shield on the sides of the body is connected to the lower part of the shell, the plastron.
consists of bone, on top of its scutes are covered with horny plates. For fixation, the ribs, vertebrae, pelvic and shoulder girdles are fused with the shell. The holes in the shell are positioned so that the limbs can be easily retracted.

Shell shape

Appearance shells depends on the environment. The shape of the shell - an amazing invention of nature for the passive protection of turtles - depends on the lifestyle of these animals. The carapace of land turtles is usually high, dome-shaped, often uneven; individual scutes can have the shape of small domes or pyramids. Carapace of turtles living in denser than air, aquatic environment, as a rule, flattened, smooth, streamlined, its dome shape is small. Sea turtles have gone even further in adapting to the aquatic environment; their shell is drop-shaped, the most perfect form for achievement high speed in water.

The jaws of turtles do not have teeth, but are equipped with powerful horny edges. The outer blade of these edges is quite sharp, and the jaw muscles are very strong. Turtles easily bite off pieces of even dense plant tissue and deftly grab moving prey. The front legs with strong claws make it possible to hold plants and caught animals while eating, and if necessary, dismembering them into easily swallowed pieces successfully copes with this procedure.

In aquatic animals they are flat and flattened, in land animals they are denser and thicker. In the same species of turtles different conditions there may be a different structure of the shells. The shell can be massive, low, light, narrow, miniature, saddle-shaped. Their shape depends on the environment - the result of adaptation.

The largest sea turtles

Sea turtles are the largest of all turtles. Real giants in the world of reptiles! An adult turtle can even cope with a shark.

The fastest among reptiles

Leatherback turtle (Dermochelys coriacea) is the fastest among reptiles, it reaches a speed of movement in water of 35 km/h. Its mass can reach up to 450 kg, its body length ranges from 1.8 to 2.1 m, and its width at the level of the front flippers is 2.1 m. A male found dead on the beach in Harlech, UK, in 1988, had a general length 2.91 m, width 2.77 m and weight 961.1 kg.

The leatherback turtle is also the best diver among turtles. In May 1987 Dr. Scott Eckert reported that a leatherback turtle wearing a pressure-recording device reached a depth of 1,200 m near the Virgin Islands.

The largest land turtle

The largest land-based members of the order Turtles are those living in the Galapagos Islands, off the west coast of northern South America, and the Aldabra Islands and Seychelles Islands in Indian Ocean. Land turtles live in deserts, steppes, and forests. They enter the water only for swimming and often while sleeping. Their shell is more massive than that of other turtles.

The largest living elephant turtle (Geochelone elephantopus elephantopus), called Goliath, is known, it is located in the reserve in Seisner, PC. Florida, USA, since 1960. Its length is 135.5 cm, width 102 cm, height 68.5 cm, and weight 385 kg.

Giant tortoises live for 200 years or more, so perhaps we can still see the same tortoises that Charles Darwin met 160 years ago. In his time, the islands were home to a population of 250,000 turtles, with 14 species. Today, 15,000 remain, three species are extinct and a fourth is critically endangered, with only one turtle of this species known.

Giant tortoises are vegetarians, eating fruits, cacti, bromeliads and other plants, and sometimes eating insects and carrion. They are able to live for many months without food or water.

Depends on temperature

Like other reptiles, turtles lack the ability to directly control their body temperature and are considered general public cold-blooded animals. But this is not entirely true: they die very quickly if the ambient temperature is much higher than the temperature range they are accustomed to. Indeed, temperature is a critical factor for the successful keeping of turtles in captivity.

Large turtles maintain stable body temperatures

Reptiles are characterized as cold-blooded animals, but this is not entirely accurate. Their body temperature is mainly determined environment, but in many cases they can regulate it and, if necessary, maintain it for more high level. When it is necessary to increase their body temperature, reptiles usually bask in the sun, absorbing its heat through the entire surface of their skin. When they start to overheat, they tend to retreat into the shade.

Some species are able to generate and retain heat within their own body tissues.
Large reptiles can maintain a more stable body temperature because their massive bodies contain more heat and have thicker skin and fat layers.

May starve

An elephant turtle can fast for up to 18 months.

The smallest turtle

U common musk turtle (Sternotherus odoratus) The length of the carapace of an adult is on average 7.6 cm, and the weight is only 227 g.

Smallest sea turtle
Adult carapace length Atlantic ridley (Lepidochelys kempii) is 50-70 cm, and the maximum weight is 80 kg.

The oldest turtle

A turtle has achieved the longest accurately determined life expectancy. Astrochelysradiata. In 1773 (1777) the individual was presented as a gift to the ruling clan of the Tonga Islands by Captain Cook. The turtle was named Tui Malila and lived to be at least 188 years old, until 1965.

Traveling Turtles

The farthest journey made by a sea animal... committed by a loggerhead sea turtle, or carriage (Caretta caretta), which was tagged and released near the California Peninsula, Mexico, in an experiment conducted at the University of Arizona, USA, was discovered 10,459 km off the coast of Japan.

The Mystery of the Migrating Sea Turtle

The sea turtle can use the Earth's magnetic field as a compass and map. The phenomenal ability of green has been experimentally confirmed sea ​​turtle (Chelonia mydas) feel the slightest changes in the Earth's magnetic field. The researchers used a giant magnetic coil the height of a two-story house, which they installed next to the aquarium.

During the experiment, scientists changed the magnetic field, trying to give it parameters similar to two areas in the north and south of Florida, and the area where the turtles were caught was located exactly in the middle between the “poles.” The reptiles, exposed to the magnetism inherent in the northern areas, swam south, while the “southerners” moved north.

In each case, the turtles swam towards the house as if they were in a place where the corresponding magnetic field actually existed. By the way, it was previously discovered that moles use a magnetic field in a similar way, and birds are helped by an internal magnetic compass.

Natural enemies

Birds of prey drop turtles from a height onto rocks and peck them out of their cracked shells. Cases are described when foxes pushed turtles from ledges onto stones for the same purpose. Jaguar in South America scoops turtles out of their natural stronghold so cleanly that travelers compared the results of his work with the results of the work of a thin sharp knife. At the same time, the jaguar prepares several turtles for its meal, turning them over on their backs, always on a level place without vegetation, where it is difficult to catch their head and legs on something in order to turn over and crawl away.

Turtles do not chew their food

... and the chewing movements visible to the observer from the outside serve only to move the piece captured in the mouth into the pharynx. Language also actively participates in this movement. Given the sharp edges of the jaws with their cutting edge, as well as the powerful muscles of the head, the terrarium enthusiast should still be quite careful with these mostly peaceful animals.

Don't give up meat

In nature, turtles also eat bird chicks, various invertebrates, and even carrion. Therefore, experts advise including pet turtles in the menu. chopped meat or pieces fresh meat by adding them to the fruit and vegetable mixture.

Aggressors in the world of turtles

Land species are calm and not aggressive; water species are more active and tend to bite. Large aquatic turtles with carapaces over 20 cm long can pinch your hand quite hard, sometimes causing blood. As a rule, turtles become active during the mating season.

The exception is Far Eastern turtle: even tiny individuals of this species bite strongly, and specimens longer than 15 cm are already dangerous. Clutching the hand, the Far Eastern tortoise powerfully squeezes its jaws, clenching them convulsively.

There are many turtles in the world that are simply dangerous to humans, including caiman and vulture. Famous snapping turtles Chelydra serpentina very biting: they grab snakes, birds on the shore and in the water, there were cases when they bit off the fingers of people swimming.

This large turtles with a shell up to 35 cm long and weighing up to 14 kg. The turtle's menacing appearance is given by its sharp jaws and short beak. This look matches its aggressive character. When defending itself, it actively throws out its head on its long neck and bites. He loves to hunt: he guards his prey for a long time and quickly grabs approaching animals with his mouth - be it fish, all kinds of small animals, even waterfowl.

Can kill large animals

Trionyx Trionyx cartilagineus- terribly biting soft shell turtle. A hungry flock of adult reptiles can bite a large animal to death.

Fierce Ridley

It is up to 80 centimeters long and feeds on both plant and animal foods. His temper is quite ferocious. When she is fished out of the water, Ridley (Lepidochelys olivacea) causes a lot of trouble: bites through oars and hands, rushes at people.

Delayed conception

There is documented evidence that females different types Box turtles become fertilized 7 years after mating with a male.

The largest eggs

... put off giant tortoises (Geochelone elephantopus and G. gigantea), living on the Galapagos Islands Their eggs are the same size as chicken eggs, and their maturation continues for 40 years or more until they reach their maximum size. They reach a length of 1.5 m and can weigh 255 kg.

Take care of yourself from birth
After laying eggs in the sand and rotting leaves, the turtles leave, exposing them to the sun. After some time, little turtles hatch. They pierce the shell with the help of a pointed growth on the snout, which soon falls off. From birth they must take care of themselves. And from birth they look the same as adults.

Only one out of a thousand
After mating, sea turtles wait until nightfall and come ashore. They dig holes in the sand and lay eggs there. The sun warms them, and soon many small turtles crawl out of the sand at the same time and immediately run to the sea. Along the way they are eaten by seagulls and crabs, and in the sea the babies are also threatened by predators. Only one in a thousand turtles will be able to return to the beach where they were born to continue their lineage.

In captivity they do not feel discomfort
There is an opinion that some species of turtles, in particular the Central Asian one, go blind and die in captivity. Just the opposite. In captivity, these turtles do not feel discomfort; with a clear regime, they quickly get used to the new place and time of feeding. They most readily eat lettuce, dandelion, the pulp of watermelons and melons, as well as cabbage, apples, and carrots. The most important thing for them is an abundance of warmth and light. For the winter, it is useful to put them into hibernation (a box with sand at a temperature of +1-5).

Fishing kills turtles
Every year, one in three sea turtles are killed as a result of fishing, and some populations may become extinct within just a few decades. International trade in turtles is prohibited, but some fishermen kill them for their meat and eggs. In some Mexican villages, cesspools are filled with turtle shells. Many of their brethren die as by-catch - being caught in the net by accident.

The scientists monitored 50 satellite-tagged green, vulture and leatherback turtles for a total of 6,000 days (300 days per turtle). Six of them were caught and brought to land – 31% of total number in a time equivalent to a year. The same percentage of turtles die every year around the world.

Capable of starving for years

Land turtles are very hardy; If we talk about the frequency of food intake, land animals may not eat food (we are, of course, talking about healthy animals kept in conditions suitable for them) for weeks or months. Cases of turtles starving for years have been described.

Very gluttonous
Aquatic turtles, as carnivores, are more impatient with food. Young individuals kept in an aquarium are very voracious; they are ready to eat with appetite every day, and several times a day. Larger aquatic turtles living in pools are ready to consume food daily, but can also go hungry for weeks, even more than a month. A case is described when marsh turtle She lived without eating for more than five years. :

Over the past 200 million, turtles have remained virtually unchanged.

Tenacious like a turtle
With its head broken to rags, a turtle can live and move for tens of days!). And one experimental specimen with its brain removed lived for six months.

Centenarians.
150 years is the normal age for land turtle. Sometimes they live 200 years or more.

Strongmen
Some species are amazing in their strength: the green sea turtle can carry as many people as can fit on its shell.

Can crawl on ice
Snapping turtles are not afraid of the cold and can crawl on ice.

Breeding rituals
Recently, oviposition sites for ridleys were found on the coast of Mexico. Once at Cape Kennedy, on the night when the next space flight was being prepared, numerous service personnel, security guards, and journalists, in the light of searchlights, saw 12 sea giants that had climbed onto the sandy shore.

Not paying attention to the people, the animals acted out a scene from one of the oldest performances in the world: each female dug a half-meter hole with her hind legs and laid 100-200 eggs. Then the holes were filled in, and the areas above them were carefully “harrowed” for better camouflage, although in front of so many people this did not make sense. Having finished laying, the turtles went into the water, where the males were waiting for them. They headed back to where they had come from, some 1000 kilometers away, each to their own pasture. Ridleys travel such vast distances to lay eggs somewhere on a sand spit without any guarantee of safety for the offspring.

Barrier to ships
Ridleys, sailing hundreds of kilometers, gathering in flocks along the way, were so numerous in the time of Columbus that they became an obstacle for ships. Nowadays, a ship with the Ceylonese zoologist Deraniyagala on board met a whole caravan of ridleys, stretching out to sea for 108 kilometers! The turtles swam at a distance of 200 meters from each other, but all in the same direction.

Lifespan of a turtle

Average duration gigantic tortoise - 40-50 years, maximum - over 100 years. The giant elephant tortoise, believed to be the oldest living creature on the planet, celebrated its 175th birthday. The hypothesis that this tortoise belonged to Darwin rests on the claim that it is one of four giant tortoises found by Darwin during his voyage to the Galapagos Islands in 1835. All four turtles were loaded on board the Beagle, on which they arrived in Plymouth.

The oldest animal is the Madagascar radiated tortoise named Tui Malila. She was given as a gift royal family Tonga by Captain Cook. When she died in 1965, she was at least 188 years old.

Turtle navigation

Over 300 years, seafarers destroyed about 10 million turtles

Thanks to them, many were made in the last century geographical discoveries: turtles provided food (that is, themselves) for entire flotillas. These giants include the Galapagos elephant tortoise, after which the islands were named Pacific Ocean. Once upon a time there were such a large number of that pirates and fishermen made a decent detour on their travels only to fill their holds with turtle meat.

After examining ship logs stored in the Library of Congress, scientists calculated that from 1831 to 1868, only 79 whaling ships took 13,013 turtles from the Galapagos Islands! According to a rough estimate, over 300 years, seafarers destroyed about 10 million individuals!

Land tortoises are not very fertile (a female Galapagos elephant tortoise lays 20 eggs per year). But they are distinguished by the fact that they live a long time (100-200 years) and are very hardy: the Galapagos elephant tortoise spent up to 12-13 months in ship holds without food and water, without showing signs of exhaustion.

Mystery Galapagos tortoises
One of the mysteries - how they got to the Galapagos Islands - is still unanswered. There were suggestions that they swam, since the Galapagos elephant is a good swimmer. But from the salty sea ​​water the turtle dies. There are also guesses that they were brought by people, but this is only a hypothesis.

Turtles vs. Vultures (video)

MOSCOW, 23 Aug- RIA News. Scientists have found the remains of an unusual reptile in southern China, which allowed them to find out what the first ancestors of the Earth's turtles, who lived in future Asia at the beginning of the Jurassic period, looked like. Their findings and photographs of the remains of the "grandfather of all turtles" were presented in the journal Nature.

Paleontologists have figured out how turtles got a strong shellTyler Lyson from Yale University (USA) and his colleagues found that the long-known reptile Eunotosaurus is the oldest turtle today and the presumed ancestor of all reptiles of this order. This allowed scientists to trace how the hard shell turtles.

"The history of turtles has been one of the main mysteries in paleontology for many decades. The discovery of the remains of Eorhynchochelys greatly clarified the situation and helped us understand how these reptiles arose," said Olivier Rieppel from the Fields Museum in Chicago (USA).

As scientists note, the history of turtle evolution remains largely a mystery. All known species extinct turtles, except for the most ancient Odontochelys and Proganochelys, already possessed a full-fledged shell. It was not clear how these reptiles turned their ribs into “armor” and acquired special respiratory muscles that allowed them to breathe without their help.

The situation did not become clearer even after the discovery of odontochelys in 2008 - the lower half of the shell was already present in this reptile. This made scientists wonder how the evolution of turtles proceeded and when their ancestors turned into a kind of modern “tortilla”.

Rieppel and his colleagues solved this problem by discovering the remains of extremely unusual creature, which resembles both primitive archosaur lizards and turtles, studying early Jurassic sediments that formed in southern China about 220 million years ago.

Ancient people made the first turtle soup 400 thousand years agoAn analysis of fossils from the famous Qesem Cave in Israel has shown that the presumed ancestors of Neanderthals and Denisovans enjoyed turtle meat, contradicting ideas about the exclusively meat diet of ancient hominids.

Carrying out excavations in the town of Heshangjing in Guizhou province, scientists came across a two-meter skeleton of a reptile, finding it almost at the same point where the first remains of Odontochelys were found, but in deeper layers of sediment.

This creature, which received the name Eorhynchochelys sinensis, or "dawn-beaked tortoise of China", was noticeably different in appearance from Odontochelys and other primitive "tortillas" of antiquity. In particular, it had a very long and thin tail, and the ribs of this reptile had not yet fused into a shell.

On the other hand, they have already taken on a disc-shaped shape, and the jaws of Eorhynchochelys sinensis have turned into a kind of beak, which all turtles have today. This fact, as Rippel notes, has become very important milestone from the point of view of studying the evolution of these reptiles.

In the past, many paleontologists believed that turtles were descendants of anapsids, older and more primitive lizards that did not have holes in their skulls. The discovery of Eorhynchochelys sinensis shows that this is not the case and confirms genetic studies indicating that family ties turtles and modern birds and crocodiles.

For two centuries, biologists have struggled unsuccessfully over the question of the origin of the hard turtle shell, and the discovery of the remains ancient turtle Odontochelys semitestacea only gave rise to new mysteries.

Some of the researchers even became related these reptiles with birds,

which, however, did not help in any way to get closer to solving the problem. Moreover, until recently, existing theories were practically not supported by fossil finds. Therefore, scientists could not compile a complete fossil record of turtles, and as a result, trace in detail the evolution of their ribs into shells.

Leopard tortoise hiding in its shell

sciencemag.org

A group of American researchers from Yale University and the National Museum of Natural History decided to take a different approach to solving this problem. Instead of looking for an unknown ancestor of turtles and trying to fill the 30-55 million year evolutionary gap, they decided to reexamine the fossils of the Permian eunotosaurus (Eunotosaurus africanus).

Eunatosaurus skeleton found in South Africa

sciencemag.org

According to one of the popular hypotheses, it is this lizard-like animal that is ancestor modern turtles.

The results of the study can be found in latest issue scientific journal Current Biology.

Eunatosaurus skeleton helps shed light on turtle shell formation

sciencemag.org

For the first time, the remains of a Permian eunotosaurus, which lived approximately 260 million years ago, were discovered by paleontologists in the last quarter of the XIX century. And quite recently, several skeletons were found on the territory of South Africa, which, as it later turned out, belonged to this ancient animal. American researchers decided to study these finds in detail and came to rather non-trivial conclusions. So, it turned out that

In Eunotosaurus and Odontochelys, as well as proganochelis There are a number of identical features, among which the nine pairs of T-shaped ribs, growths on the perichondral bone ring and special respiratory muscles are especially notable.

This is what Tylor Lyson, the head of this study, told Gazeta.Ru, who discovered Odontochelys semitestacea, now at Yale University: “With the complete skeleton of Eunotosaurus at our disposal, we were able to make some amazing discoveries! The structure of its ribs is quite consistent with our theories about the evolution of the shell. However, the most amazing discoveries are yet to come: fusing more than fifty bones into a shell means completely changing the ventilation system of the lungs. And it’s very difficult to explain this: such changes have been going on for millions of years.”

From eunatosaurus to turtle

sciencemag.org

It is worth noting that the conclusions drawn by scientists are by no means final, since

There are still supporters of the origin of turtles from discosauriscus, although their theory does not have such a broad evidence base.

It will be possible to close the discussion only after finding some intermediate link in evolution between the notorious Eunotosaurus and Odontochelys.

There are old-timers among both people and animals. Turtles are considered the most prone to long life, especially if they live in ideal conditions– acceptable climate, abundant and healthy diet, communication with relatives. What is the oldest turtle on the planet?

Samira

This animal belonged to the Galapagos tortoise breed. She lived to be 270 years old (according to other sources - 315), dying in 2006 in the Cairo Zoo, as they say, of old age. Samira was donated to the park by the last king of the state, Farouk, who has a weakness for exotic animals. At the end of her life, Samira practically did not move.

Advaita

The second most old turtle in the world belonged to a species native to the Seychelles and lived for approximately 250 years. Back in the 19th century, English soldiers delivered it from Seychelles and presented to Lord Clive before he went home in 1867. Earlier, in the middle of the 18th century, the lord was sent to India with the aim of establishing a colonial regime there. During his absence, the animal lived in the palace garden. In 1875, it was decided to place it in the Calcutta Zoo (although there is still no official confirmation that this is the same turtle).

In March 2006, the reptile was found dead by zoo staff. This was predictable, since Advaita had been feeling unwell for a couple of days before this. The impressive shell was preserved as a memory of the favorite of several generations of townspeople. Later, an examination was carried out to accurately determine the age of the turtle.

The exact name of the Advaita variety was "aldabra", in accordance with the atoll of the same name. This UN-protected site is home to another 150,000 of these turtles. Average weight the animal weighs 120 kg.

Tui Malila

According to legend, this Madagascar radiated tortoise was presented by Captain James Cook to the head of the Aborigines of Tonga in 1773. There is no official evidence of this, but if you believe it, it turns out that at the time of her death in 1966 she was 193 years old. By this point, she was already blind and could barely eat, so zookeepers had to move her mouth directly to the feeder.

Jonathan

This huge, imposing Seychelles tortoise was brought to St. Helena in 1882 along with three other specimens, each approximately 50 years old. Jonathan, now 185 years old, lives in the garden of the home of the island's governor, Spencer Davis. In 1900, a photograph was taken of a huge turtle lying at the feet of a Boer War prisoner. In 2008, confirmation was published that this particular turtle was Jonathan, who at that time was about 70 years old.

Harietta

At one time, an elephant tortoise named Garietta was included in the Guinness Book of Records for his long life– in 2005 she was 175 years old, all of which she spent in captivity. It is not known exactly who caught her; according to one version, it was Charles Darwin, according to another - ordinary whalers.

For the last 30 years of its life, the animal was a real attraction at the Queensland Zoo.

IN wildlife, according to scientists, only a dozen of its brothers remain.

It should be noted that the population could have been larger if Harietta had not been caught: until the end of her life she was capable of fertilization, but did not have a partner.

The amazing turtle's favorite food was hibiscus, and she also loved to eat eggplant and parsley, and was generally quite unpretentious and modest. Zoo workers talk about this.

Timothy

In April 2004, another of the honored long-lived turtles died. At that time, Timothy was 160 years old. He spent amazing life, serving as a mascot on a British warship, then sailed with soldiers to China and East India, and retired 100 years before his death. All this time, the turtle was crawling in the garden around Powderham Castle, located in Devon, and during hibernation hiding among the rose bushes. Then a sign was attached to it asking not to disturb. In 1926, all fans of the turtle were in for an unexpected surprise: it turned out that Timothy was a female. In general, we can say that the animal led a rather active lifestyle compared to other relatives and peers.

These are the amazing animals that lived and continue to live on our planet. I would like to believe that all representatives of the animal world will be just as lucky with their living conditions so that they can lead a long, fruitful life.