Plesiosaur interesting facts. Plesiosaurs. Glass pyramids in the Bermuda Triangle

Euryapsids are a group of reptiles related to diapsids and separated from them in the early stages of evolution, retaining many primitive structural features. Please note that they are all semi-aquatic or aquatic animals. The fact is that these creatures are not dinosaurs either - we have not yet reached dinosaurs (and, perhaps, we will not get there, because what could be more accordion-like than a hit parade of the most large dinosaurs?). Aquatic dinosaurs are practically unknown to science, with the exception of large sauropods, and even those can be called aquatic with a big stretch. What's the connection here? I'll explain now.

Almost everyone knows (at least they have heard it somewhere) that snake meat tastes like chicken. To be precise - chicken fillet, its pectoral flight muscles atrophied as unnecessary - “white meat”. White muscle is poor (compared to red) in myoglobin and mitochondria, and the energy for muscle contractions is obtained mainly from the anaerobic breakdown of glucose to lactic acid. This reaction does not require oxygen, and its speed depends little on temperature, which is important for a cold-blooded animal. However, lactic acid that accumulates as a result of glycolysis is a metabolic poison, and literally after a few minutes of intense work, the white muscles practically lose the ability to further contractions; Spontaneous breakdown of lactic acid and restoration of performance requires several hours. White muscles are fundamentally unsuitable for prolonged work, therefore, when observing modern reptiles in the terrarium it seems that most of the time they do nothing but do nothing.

In myoglobin-rich red muscles, lactic acid is only an intermediate product, which is then “burned” with oxygen in the mitochondria to carbon dioxide and water with the release of huge amounts of energy. However, this reaction requires high temperature environment, and in the absence of it - warm-bloodedness, to ensure which most of the energy received is spent on heating the body, therefore mammals and birds, even at rest, consume ten times more food than cold-blooded reptiles. Another owner of red muscles - dinosaurs - was not all warm-blooded (in Mesozoic climate this was not critical) and did not eat so much, but their need for oxygen was noticeably higher than that of their more primitive counterparts - euryapsids, turtles, scaly animals and crocodiles.

So it turns out that primitive owners of “white meat” with a slow metabolism and a relatively low need for oxygen and high temperature environment turned out to be much better adapted to an aquatic lifestyle than “advanced” dinosaurs. The disadvantages of anaerobic metabolism - rapid muscle fatigue during intense work - disappear in water, where the body of a living creature weighs almost nothing (studies of modern marine iguanas have shown that when moving in water, their metabolic costs are only a quarter of those required for movement on land). The closest relatives of dinosaurs - crocodiles - unlike them, did not acquire, as unnecessary, either warm-bloodedness or red muscles (and, as a result, “vertical” limbs), and they were right: unlike more “advanced” dinosaurs, crocodiles are still are alive, but the mammalian predators that reigned in the Cenozoic never replaced them in freshwater bodies. However, about crocodiles later, but for now here are the euryapsids:

Placodontia were a group of marine reptiles close to nothosaurs and plesiosaurs, and had some external resemblance to turtles (especially the genus Henodus) and existed until the end of the Triassic. The largest member of the group was the Middle Triassic Placodus gigas from southwestern Asia, reaching a little more than 1.5 m in length and feeding, like other placodonts, on crustaceans and mollusks that it found in the sea. Placodonts, apparently, were not fully aquatic animals, and their lifestyle most likely resembled modern Galapagos iguanas, with the only difference being that iguanas fed on algae.

Notosauria (Nothosauria)- a group of piscivorous Triassic reptiles. Based on its structural features, it is considered the ancestor of plesiosaurs. The largest member of the group was Ceresiosaurus calcagnii from the Middle Triassic of Europe, reaching four meters in length.

Squad Plesiosaurs (Plesiosauria) unites aquatic euryapsids that used exclusively the fore and hind limbs, and not the tail, to move underwater, and is divided into two suborders: pliosauroids and plesiosauroids. The former have short necks and massive heads, while the latter have developed necks and relatively small heads. From the pliosauroids comes not only the largest plesiosaur, but also supposedly the largest predator the planet has ever seen - this Liopleurodon ferox, a giant marine predator of the Upper Jurassic. There is a debate about the size of this animal: most authors do not give it more than 18 m in length; however, in “Walking with Dinosaurs” he was awarded a length of 25 m due to the fact that the eighteen-meter specimen discovered in 2003 in Mexico was, according to a number of characteristics, a young individual, and, according to the authors of the film, could well grow to 25 m over time.
(approx. translation: If we talk not about the supposed, but about the documented size of the animal, then Liopleurodon does not get the laurels of the largest predator on the planet - the 23-meter Shonisaurus mentioned below and the modern sperm whale, which is supposedly ahead of it in mass, are vying for them ( Physeter macrocephalus), the largest males of which reach a length of 20.5 m and weigh up to 57 tons.)

The suborder of plesiosauroids is represented by marine reptiles with long necks, actually known as plesiosaurs. The mythical monster of Loch Ness is traditionally considered to be a plesiosaur, so their appearance has been replicated and is known to many. Plesiosauroids seemed to consist of two creatures: they themselves were not fast swimmers: their body with flippers resembled that of sea ​​turtle and was not capable of dexterous maneuvers - but a small head on a long flexible neck, which played the role of a hunter, was capable of them. The largest representative of the suborder - found in North America Elasmosaurus platyurus from Cretaceous period, reaching a total length of 15 m.

The author of the original article, for some unknown reason, neglected the detachment ichthyosaurs (Ichthyosauria)– euryapsid marine reptiles that had a body shape similar to fish and dolphins. Ichthyosaurs were completely associated with the water element and could not get to the shore, so they were ovoviviparous - skeletons of females were found with skeletons of the embryo inside, located, like cetaceans, tail first. They may have hunted at night or at great depths: a typical ichthyosaur had very large eyes, protected from water pressure by a ring of bones. Additionally, apparently, there were some kind of skin receptors that detected the movement of water (or sound waves) like the fish lateral line, as indicated by traces of nerves and blood vessels on the bones of the skull, and served for orientation under water (in cetaceans, this function is performed by echolocation ). The largest species described from discovered fossils is Shonisaurus sikanniensis from the Late Triassic of polar Canada (a skeleton about 23 meters long was described in 2003). It is the largest ichthyosaur known to science and the largest discovered marine reptile of all time.

To be continued

At the beginning of the 20th century, they already knew that the giant sea snake was not a snake. What animal was mistaken for a sea snake? Naval officer Gould tried to find out. In 1930 he published The Story of the Sea Serpent. For more than a hundred pages, the captain discusses the events associated with this sea monster.

Captain Gould writes that eyewitnesses usually saw only those parts of the animal's body that rose above the surface of the water.
What are these body parts? Snake neck and snake head. However, such a neck and such a head are not only found in snakes, but also in other animals.

This was, for example, the “long dragon” - plesiosaur. At all times there were the most “necked” animals. Elasmosaurus, which had 76 neck vertebrae, could have easily peered through a third-story window! Gould wrote: “...if not a direct descendant of a plesiosaur, then a descendant of some animal close to it.”
If we read ancient descriptions, we will find in them references to monsters similar to a plesiosaur.

The priest Hans Egede wrote in 1763: “As for strange fish or monsters, Lately Only one case can be noted. The sea monster was seen in 1734 at 64 degrees northern latitude. Its dimensions were enormous and its head rose above the water to the height of the ship's top. It was 3-4 ship hulls long. The muzzle was long and pointed. The monster breathed like a whale. The fins were long and wide. The body is covered with a folded shell. The skin is spotty. The back of the body is like a reptile. When this creature plunged into the water, it turned upside down and its tail rose out of the water so much that its end was separated from the body by the entire length of the ship.

U plesiosaur there were four huge fins with which he raked, like modern turtles. This method of movement was not the fastest: Sharks, dolphins, most bony fish move with the help of a caudal fin (something like a propeller) appear to be the fastest aquatic animals!

Plesiosaur with its oar-like fins, it was superior to them in only one respect - it was more nimble and could easily turn on the spot, which was, of course, very convenient when fishing. In the drawing in Egede’s book, only the front, less important fins are visible, while the rear ones are hidden under water .

Does the plesiosaur exist to this day or not?

Today it is assumed that the Lochios monster is nothing more than a living plesiosaur. It is possible that several monsters live in the lake, and they sometimes disturb tourists (or vice versa). In recent decades, the famous monster has often been written about in the press. Particularly great attention was paid to it in 1934, when, as many believe, it was discovered. However, in Scottish legends, the monster living in Loch Ness was mentioned already at the beginning of the fifteenth century and in subsequent centuries the monster was not forgotten, but rumors about it did not go beyond the borders of Scotland.

The real “career” of the monster began in the thirties of our century, when numerous films were dedicated to him (using models, of course). Currently, one scientific society is seriously studying the monster. Using the latest photographic and film technology, they are trying to obtain documentary evidence of its existence. Nesen is hunted using radar and ultrasonic equipment. So far to no avail.

Could it be prehistoric creature survive millions of years? Why not? After all, turtles, crocodiles, and sharks were contemporaries of the plesiosaur and still survived safely to this day.

We consider plesiosaurs to be prehistoric animals only because they went extinct about 70 million years ago. The question is, is this group of animals really extinct?
Maybe today some of its representatives still live in Loch Ness or in the seas and oceans? After all, animals that scientists considered long ago extinct have survived in the seas.

After several specimens of coelacanth, a fish of the Devonian period, were discovered off the coast of Africa, scientists became more cautious in their judgments in this regard, but let us pose the question: does everything previously said really apply to the plesiosaur?

The answer will be no. There is no living plesiosaur. Why are we so categorical? Because plesiosaurs were reptiles, and reptiles breathe with lungs, like lizards or whales. Consequently, the plesiosaur, if it had lived to this day, could not have hidden in the depths of the sea, since it would have needed to rise to the surface for air every 10-20 minutes. Thus, if a plesiosaur existed in our time, it would not have gone unnoticed by fishermen or whalers, and we would have it scientific description, as we have the description of the sea cow made by Steller.
It's possible that plesiosaurs died out not 70 million years ago, but much later, but today they are not there.

History of discovery

Diversity

There are two suborders of plesiosaurs - the long-necked plesiosaurids (including the family Cymoliosaurus) and the short-necked pliosaurids.

The largest plesiosaurs are the pleschiosauroid elasmosaurids, such as members of the genera Mauisaurus, Elasmosaurus, Hydrotherosaurus, reaching 20, 14 and 13 m, respectively (although estimates of the length of the first at 20 m are quite controversial). Some pliosauroids, such as Kronosaurus and Pliosaurus, although reaching slightly less overall length, had significantly more weight.

Reproduction

Disputes about the methods of reproduction of plesiosaurs have been going on for 200 years.

Many experts believed that due to the large weight, it was difficult for the animal to get ashore and lay eggs, that is, they must have been viviparous. The first direct evidence of this was obtained after a careful study of the fossilized skeleton of a plesiosaur (they were in the basement of the Natural History Museum in Los Angeles for about 20 years).

Plesiosaurs in world culture

Plesiosaurs have appeared in many works of fiction. The first book where a plesiosaur was mentioned was Journey to the Center of the Earth by Jules Verne, where a long-necked plesiosaur is found. In A. Conan Doyle's novel The Lost World, a small freshwater plesiosaur was mentioned that lived in the central lake-plateau. In the novel by V. A. Obruchev there was a description of two plesiosaurs fighting over fish. In the book “The Secret of Two Oceans” the heroes discover an underwater colony of plesiosaurs, which in the process of evolution acquired the ability to breathe under water (the word “plesiosaur” is mentioned only at the end, during scientific conference). Almost the entire discovered flock was destroyed during an attack on the team. The most faithful image of a plesiosaur is found in the work of Harry Adam Knight “Carnosaurus”.

Plesiosaurs have also appeared in many films. The most famous and memorable films by the public are the Japanese horror film The Legend of the Dinosaur and the British adventure film The Land That Time Forgot.

In films, plesiosaurs were mainly represented as giant, bloodthirsty monsters. More accurately, plesiosaurs were introduced in the BBC television series Walking with Dinosaurs.

The plesiosaur appears in the 22nd episode of the 3rd season of the X-files - "Quagmire". Plesiosaurs have also appeared in the video games Dino Crisis 2 and Turk: Evolution.

Plesiosaurs in modern mythology

• The widely known Nessie, supposedly living in the Scottish Loch Ness, according to some researchers, may be the last representative of plesiosaurs (and falsifiers portrayed her in accordance with old ideas about plesiosaurs as creatures with a movable neck capable of rising high above the water - see. for example the famous photo from the newspaper Daily Mail for 1934; It has now been established that the neck of these creatures was practically motionless). Plesiosaurs can be seen in the descriptions of some other lake monsters. All of these lakes are located at high latitudes of the Northern Hemisphere and have karst faults at the bottom.

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Literature

• Basics of paleontology. Amphibians, reptiles and birds. - M., 1964.

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Excerpt characterizing Plesiosaurs

- This is the current upbringing! “Even abroad,” said the guest, “this young man was left to his own devices, and now in St. Petersburg, they say, he did such horrors that he was expelled from there with the police.
- Tell! - said the countess.
“He chose his acquaintances poorly,” Princess Anna Mikhailovna intervened. - The son of Prince Vasily, he and Dolokhov alone, they say, God knows what they were doing. And both were hurt. Dolokhov was demoted to the ranks of soldiers, and Bezukhy’s son was exiled to Moscow. Anatoly Kuragin - his father somehow hushed him up. But they did deport me from St. Petersburg.
- What the hell did they do? – asked the Countess.
“These are perfect robbers, especially Dolokhov,” said the guest. - He is the son of Marya Ivanovna Dolokhova, such a respectable lady, so what? You can imagine: the three of them found a bear somewhere, put it in a carriage and took it to the actresses. The police came running to calm them down. They caught the policeman and tied him back to back to the bear and let the bear into the Moika; the bear is swimming, and the policeman is on him.
“The policeman’s figure is good, ma chere,” shouted the count, dying of laughter.
- Oh, what a horror! What's there to laugh about, Count?
But the ladies couldn’t help but laugh themselves.
“They saved this unfortunate man by force,” the guest continued. “And it’s the son of Count Kirill Vladimirovich Bezukhov who is playing so cleverly!” – she added. “They said he was so well-mannered and smart.” This is where all my upbringing abroad has led me. I hope that no one will accept him here, despite his wealth. They wanted to introduce him to me. I resolutely refused: I have daughters.
- Why do you say that this young man is so rich? - asked the countess, bending down from the girls, who immediately pretended not to listen. - After all, he only has illegitimate children. It seems... Pierre is also illegal.
The guest waved her hand.
“He has twenty illegal ones, I think.”
Princess Anna Mikhailovna intervened in the conversation, apparently wanting to show off her connections and her knowledge of all social circumstances.
“That’s the thing,” she said significantly and also in a half-whisper. – The reputation of Count Kirill Vladimirovich is known... He lost count of his children, but this Pierre was beloved.
“How good the old man was,” said the countess, “even last year!” I have never seen a more beautiful man.
“Now he’s changed a lot,” said Anna Mikhailovna. “So I wanted to say,” she continued, “through his wife, Prince Vasily is the direct heir to the entire estate, but his father loved Pierre very much, was involved in his upbringing and wrote to the sovereign... so no one knows if he dies (he is so bad that they are waiting for it) every minute, and Lorrain came from St. Petersburg), who will get this huge fortune, Pierre or Prince Vasily. Forty thousand souls and millions. I know this very well, because Prince Vasily himself told me this. And Kirill Vladimirovich is my second cousin on my mother’s side. “He baptized Borya,” she added, as if not attributing any significance to this circumstance.
– Prince Vasily arrived in Moscow yesterday. He’s going for an inspection, they told me,” the guest said.
“Yes, but, entre nous, [between us],” said the princess, “this is an excuse, he actually came to Count Kirill Vladimirovich, having learned that he was so bad.”
“However, ma chere, this is a nice thing,” said the count and, noticing that the eldest guest was not listening to him, he turned to the young ladies. – The policeman had a good figure, I imagine.
And he, imagining how the policeman waved his arms, laughed again with a sonorous and bassy laugh that shook his entire plump body, as people laugh who have always eaten well and especially drunk. “So, please, come and have dinner with us,” he said.

There was silence. The Countess looked at the guest, smiling pleasantly, however, without hiding the fact that she would not be at all upset now if the guest got up and left. The guest's daughter was already straightening her dress, looking questioningly at her mother, when suddenly from the next room several men's and women's feet were heard running towards the door, the crash of a chair being snagged and knocked over, and a thirteen-year-old girl ran into the room, wrapping something in her short muslin skirt, and stopped in the middle rooms. It was obvious that she accidentally, with an uncalculated run, ran so far. At the same moment a student with a crimson collar, a guards officer, a fifteen-year-old girl and a fat, ruddy boy in a children's jacket appeared at the door.
The count jumped up and, swaying, spread his arms wide around the running girl.
- Oh, here she is! – he shouted laughing. - Birthday girl! Ma chere, birthday girl!
“Ma chere, il y a un temps pour tout, [Darling, there is time for everything,” said the countess, pretending to be stern. “You keep spoiling her, Elie,” she added to her husband.
“Bonjour, ma chere, je vous felicite, [Hello, my dear, I congratulate you,” said the guest. – Quelle delicuse enfant! “What a lovely child!” she added, turning to her mother.
A dark-eyed, big-mouthed, ugly, but lively girl, with her childish open shoulders, which, shrinking, moved in her bodice from fast running, with her black curls bunched back, thin bare arms and small legs in lace pantaloons and open shoes, I was at that sweet age when a girl is no longer a child, and a child is not yet a girl. Turning away from her father, she ran up to her mother and, not paying any attention to her stern remark, hid her flushed face in the lace of her mother’s mantilla and laughed. She was laughing at something, talking abruptly about a doll that she had taken out from under her skirt.
– See?... Doll... Mimi... See.
And Natasha could no longer speak (everything seemed funny to her). She fell on top of her mother and laughed so loudly and loudly that everyone, even the prim guest, laughed against their will.
- Well, go, go with your freak! - said the mother, feigning angrily pushing her daughter away. “This is my youngest,” she turned to the guest.
Natasha, taking her face away from her mother’s lace scarf for a minute, looked at her from below through tears of laughter and hid her face again.
The guest, forced to admire the family scene, considered it necessary to take some part in it.
“Tell me, my dear,” she said, turning to Natasha, “how do you feel about this Mimi?” Daughter, right?
Natasha did not like the tone of condescension to childish conversation with which the guest addressed her. She did not answer and looked at her guest seriously.
Meanwhile, all this young generation: Boris - an officer, the son of Princess Anna Mikhailovna, Nikolai - a student, the eldest son of the count, Sonya - the count's fifteen-year-old niece, and little Petrusha - the youngest son, all settled in the living room and, apparently, tried to keep within the boundaries of decency the animation and gaiety that still breathed from every feature of them. It was clear that there, in the back rooms, from where they all ran so quickly, they were having more fun conversations than here about city gossip, the weather and Comtesse Apraksine. [about Countess Apraksina.] Occasionally they glanced at each other and could hardly restrain themselves from laughing.
Two young men, a student and an officer, friends since childhood, were the same age and both were handsome, but did not look alike. Boris was a tall, blond young man with regular subtle features calm and beautiful face; Nikolai was a short, curly-haired young man with open expression faces. Black hairs were already showing on his upper lip, and his whole face expressed impetuosity and enthusiasm.
Nikolai blushed as soon as he entered the living room. It was clear that he was searching and could not find anything to say; Boris, on the contrary, immediately found himself and told him calmly, jokingly, how he had known this Mimi doll as a young girl with an undamaged nose, how she had grown old in his memory at the age of five and how her head was cracked all over her skull. Having said this, he looked at Natasha. Natasha turned away from him, looked at her younger brother, who, with his eyes closed, was shaking with silent laughter, and, unable to hold on any longer, jumped and ran out of the room as quickly as her fast legs could carry her. Boris didn't laugh.
- You seemed to want to go too, maman? Do you need a carriage? – he said, turning to his mother with a smile.
“Yes, go, go, tell me to cook,” she said, pouring out.
Boris quietly walked out the door and followed Natasha, the fat boy angrily ran after them, as if annoyed at the frustration that had occurred in his studies.

The now most popular pliosaur instilled fear in the marine inhabitants of Jurassic Europe. The range of its potential food is very wide. It could even include other pliosaurids, such as Peloneustes. Latin name comes from the ancient Greek phrase "smooth-sided tooth." Despite the fact that the genus has been known since the end of the 19th century, a relatively complete image was restored relatively recently.

Business card

Time and place of existence

There were Liopleurodons in the middle and end Jurassic period, about 166.1 - 157.3 million years ago (Callovian and Oxfordian stages). They were distributed in the territory of modern England and France.

Dynamic illustration by paleoartist Jaime Chirinos. Swift attack of a liopleurodon on a plesiosaur.

Types and history of discovery

There are now two generally recognized types: Liopleurodon ferox(typical and largest) and Liopleurodon pachydeirus.

Fossil remains of the future Liopleurodon were discovered at the end of the 19th century in several areas of France. These were three isolated teeth. In 1873, they were described and named by the French paleontologist Henri Emile Sauvage. At the beginning of the article, we explained the generic name Liopleurodon. The specific name ferox is translated from Latin as “fierce.”

In a painting by English paleoartist Phil Wilson, mosasaurs were attacked by a hungry Liopleurodon. This is the author’s creative assumption: mosasaurs appeared already in the Cretaceous period.

But only one of the teeth, a find from Boulogne-sur-Mer (Nord-Pas-de-Calais region, north of the country), is today fairly accurately attributed to the original Liopleurodon. The specimen identified as BMNH R3536 is the current holotype. Nowadays, the rocks of this area are classified as the Oxford Clay formation (Oxford clay).

The Jurassic predator soars majestically in calm waters.

This was followed by new finds from France and England, from the same formation and new localities. To date, Liopleurodon ferox is known from several partial skeletons, and Liopleurodon pachydeirus only from a set of articulated cervical vertebrae.

In addition, fragmentary remains from the Jurassic of Germany and the Cretaceous of Argentina are temporarily attributed to Liopleurodon. However, there is a high probability that these are independent genera, especially in the second case.

Body structure

The body length of Liopleurodon reached 6.39 meters. The height is up to 1.5 meters. It weighed up to 5 tons.

Liopleurodon and Human Size Comparison from Prehistoric Wildlife.

The myth of 25 meters and 150 tons

In 1999, the famous documentary series “Walking with Dinosaurs” was released, in which Liopleurodon is credited with non-existent dimensions. Moreover, incredible values ​​were indicated (25 m and 150 tons), apparently to create a stunning effect and contrast modern sperm whale or blue whale. Unfortunately, these numbers were quickly picked up and spread by popular sources without any further verification.

In fact, the length of the largest Liopleurodon is estimated by paleontologists at 6.39 m, and the mass is a maximum of 5 tons (moderate estimates - 2.5 tons). Moreover, currently the largest described pliosaur Pliosaurus funkei(unofficial name - Predator X from Spitsbergen, by the way, also often appears with inflated dimensions) does not exceed 12.8 m.

We are not even talking about 20 or even 25 meters yet. After all, even with the indicated data, the pliosaur was so strong that it could cope with almost any Mesozoic marine target.

Below is a typical excerpt from the film. Ophthalmosaurus looks microscopic compared to Liopleurodon. In reality, this ichthyosaur grew up to 5 meters, that is, it was of comparable size.

Other aspects

The Jurassic pliosaurid moved with the help of four wide flippers. Although Liopleurodon was unlikely to match the speed of sharks or ichthyosaurs, it could more than make up for this with its high acceleration. Moreover, the synchronized movements of four flippers made it possible to instantly make colossal jerks.

The length of the largest Liopleurodon skull (NHM R3536) reaches 1.54 m. Most of it is occupied by elongated jaws filled with huge and sharp cone-shaped teeth. The posterior region has been expanded during evolution to accommodate powerful muscles, as in modern crocodiles. The body of the Mesozoic plesiosaur was voluminous and streamlined, and the neck was very short. This was exactly what was needed to support and control the massive head.

Artistic reconstruction of Liopleurodon by English paleoartist and plesiosaur specialist Adam Smith.

Traditionally, for pliosaurs, the body ended with a relatively short tail. Overall, Liopleurodon was a well-armed member of the pliosaurid family.

Liopleurodon skeleton

The photo shows an exhibit of the species Liopleurodon ferox from the Paleontological Museum (Tübingen, Germany). This is one of the most complete specimens (length - about 4.5 m).

Below is a close-up of his skull.

And finally the front view.

Nutrition and lifestyle

According to a number of characteristics, Liopleurodon was the apex marine predator of its era. Only in some locations could it be rivaled by other pliosaurs of comparable or even larger sizes, such as the formidable Simolestes. Perhaps Liopleurodon felt equally comfortable both in deep water and in warm waters. shallow seas then Europe.

Liopleurodon could eat all kinds of fish (for example, primitive ray-finned lepidotes (Lepidotes)), cephalopods, as well as other prehistoric lizards. Ichthyosaurs such as Ophthalmosaurus and less armed plesiosaurs such as Cryptoclidus, Pelonevs or Muraenosaurus could easily be attacked.

Three-dimensional scene from Italian designer Ivan Stalio. Liopleurodons attack a school of small ichthyosaurs.

In addition, there were other potential targets - Mesozoic crocodylomorphs. After all, the narrow-snouted thalatosuchians Metriorhynchus and Steneosaurus found shelter and food in soft waters. Hypothetically, Jurassic pliosaurs could even hunt the giant Leedsichthys (especially if they were allowed to attack a large prey in pairs or larger groups), although it is unlikely that these formed the basis of their diet.

Male Liopleurodon by the duo of French 3D designers Marc Boulet and Sylvie Lorrain.

Powerful fins and a streamlined body made it possible to quickly gain speed, and long strong jaws with sharp teeth they were able to overcome even strong scales. Perhaps Liopleurodon and similar pliosaurs were masters of ambush technology in their own way. With the help of sensitive nostrils, they could detect the smells of approaching animals.

Video

Excerpt from documentary film"Walking with Dinosaurs" Liopleurodon pounces on a Eustreptospondylus that carelessly wandered onto the sandbank.

Fragment of the feature-documentary film "Walking with sea ​​monsters"Observation of a plesiosaur in its native habitat.

Excerpts from the science fiction series "Jurassic Portal", where Liopleurodon is also involved.

Thanks to the finds recent years The study of sea lizards of the Mesozoic, which for a long time remained in the shadow of their distant terrestrial relatives - dinosaurs, is experiencing a real renaissance. Now we can quite confidently reconstruct the appearance and habits of giant aquatic reptiles - ichthyosaurs, pliosaurs, mosasaurs and plesiosaurs.

The skeletons of aquatic reptiles became known to science among the first, playing important role in the development of the theory of biological evolution. The massive jaws of a mosasaurus, found in 1764 in a quarry near the Dutch city of Maastricht, clearly confirmed the fact of the extinction of animals, which was a radically new idea at that time. And in early XIX centuries, discoveries of skeletons of ichthyosaurs and plesiosaurs made by Mary Anning in southwestern England provided rich material for research in the still emerging field of the science of extinct animals - paleontology.

In our time marine species reptiles - saltwater crocodiles, sea snakes and turtles, and Galapagos iguana lizards - make up only a small proportion of the reptiles living on the planet. But in the Mesozoic era (251-65 million years ago) their number was incomparably greater. This was apparently facilitated warm climate, which allowed animals unable to maintain a constant body temperature to feel great in water, an environment with a high heat capacity. In those days, sea lizards roamed the seas from pole to pole, occupying the ecological niches of modern whales, dolphins, seals and sharks. For more than 190 million years, they formed a “caste” of top predators, hunting not only fish and cephalopods, but also each other.

Back in the water

Like aquatic mammals - whales, dolphins and pinnipeds, sea lizards descended from air-breathing land-based ancestors: 300 million years ago, it was reptiles that conquered land, managing, thanks to the appearance of eggs protected by a leathery shell (unlike frogs and fish), to move from reproduction to water to reproduce outside the aquatic environment. Nevertheless, for one reason or another, one or another group of reptiles at different periods again “tried their luck” in the water. It is not yet possible to accurately indicate these reasons, but, as a rule, the development of a new niche by a species is explained by its unoccupied position, the availability of food resources and the absence of predators.

The real invasion of lizards into the ocean began after the largest Permian-Triassic extinction event in the history of our planet (250 million years ago). Experts are still arguing about the causes of this disaster. Various versions have been put forward: the fall of a large meteorite, intense volcanic activity, a massive release of methane hydrate and carbon dioxide. One thing is clear - in an extremely short period of time, by geological standards, from all the diversity of species of living organisms, one cannot become a victim. environmental disaster Only one in twenty succeeded. Empty warm seas provided the “colonizers” with great opportunities, and that is probably why in Mesozoic era Several groups of marine reptiles arose at once. Four of them were truly unparalleled in number, diversity and distribution. Each group - ichthyosaurs, plesiosaurs, their relatives the pliosaurs, and mosasaurs - consisted of predators that occupied the top of the food pyramids. And each of the groups gave birth to colossi of truly monstrous proportions.

The most important factor that determined the successful development of the aquatic environment by Mesozoic reptiles was the transition to viviparity. Instead of laying eggs, females gave birth to fully formed and fairly large young, thereby increasing their chances of survival. Thus, the life cycle of the reptiles discussed here now took place entirely in the water, and the last thread connecting the sea lizards with the land was broken. Subsequently, apparently, it was this evolutionary acquisition that allowed them to leave shallow waters and conquer the open sea. Not having to go ashore removed size restrictions, and some marine reptiles took advantage of gigantism. Growing up big isn't easy, but once you've grown up, try to beat him. He will offend anyone himself.

Ichthyosaurs - bigger, deeper, faster

The ancestors of fish lizards-ichthyosaurs, who mastered aquatic environment about 245 million years ago, they were small inhabitants of shallow waters. Their body was not barrel-shaped, like those of their descendants, but elongated, and its bending played an important role in movement. However, within 40 million years appearance ichthyosaurs changed significantly. The initially elongated body became more compact and ideally streamlined, and the caudal fin with a large lower blade and a small upper one in most species was transformed into almost symmetrical.

Paleontologists can only guess about the family relationships of ichthyosaurs. It is believed that this group separated very early from the evolutionary trunk, which later gave rise to such branches of reptiles as lizards and snakes, as well as crocodiles, dinosaurs and birds. One of the main problems still remains the lack of a transitional link between the terrestrial ancestors of ichthyosaurs and primitive marine forms. The first fish lizards known to science are already completely aquatic organisms. It is difficult to say what their ancestor was.

The length of most ichthyosaurs did not exceed 2–4 meters. However, among them there were also giants, reaching 21 meters. Such giants included, for example, Shonisaurs, who lived at the end Triassic period, about 210 million years ago. These are some of the largest marine animals that have ever lived in the oceans of our planet. Except huge size These ichthyosaurs were distinguished by a very long skull with narrow jaws. To imagine a shonisaurus, as one American paleontologist joked, you need to inflate a huge rubber dolphin and greatly stretch its face and fins. The most interesting thing is that only the young had teeth, while the gums of the adult reptiles were toothless. You may ask: how did such colossi eat? To this we can answer: if Shonisaurs were smaller, then one could assume that they chased prey and swallowed it whole, as do swordfish and its relatives - marlin and sailfish. However, twenty-meter giants could not be fast. Perhaps they fed themselves with small schooling fish or squid. There is also an assumption that adult shonisaurs used a filtration apparatus like a whalebone, which allowed them to strain plankton from the water. By the beginning of the Jurassic period (200 million years ago), species of ichthyosaurs appeared in the seas, relying on speed. They deftly pursued fish and swift belemnites - extinct relatives of squids and cuttlefish. According to modern calculations, the three- to four-meter ichthyosaur stenopterygius developed a cruising speed no less than one of the most fast fish, tuna (dolphins swim twice as slow) - almost 80 km/h or 20 m/s! In water! The main propellant of such record holders was a powerful tail with vertical blades, like those of fish.

In the Jurassic period, which became the golden age of ichthyosaurs, these lizards were the most numerous marine reptiles. Some species of ichthyosaurs could dive to depths of up to half a kilometer or more in search of prey. These reptiles could distinguish moving objects at such a depth due to the size of their eyes. So, the diameter of the eye of Temnodontosaurus was 26 centimeters! Only the giant squid has more (up to 30 centimeters). The eyes of ichthyosaurs were protected from deformation during rapid movement or at great depth by a peculiar eye skeleton - supporting rings consisting of more than a dozen bone plates developing in the shell of the eye - the sclera.

The elongated muzzle, narrow jaws and shape of the teeth of fish lizards indicate that they ate, as already mentioned, relatively small animals: fish and cephalopods. Some species of ichthyosaurs had sharp, conical teeth that were good for grabbing nimble, slippery prey. In contrast, other ichthyosaurs had broad teeth with blunt or rounded tips to crush the shells of cephalopods such as ammonites and nautilids. However, not so long ago, the skeleton of a pregnant female ichthyosaur was discovered, inside which, in addition to fish bones, they found the bones of young sea turtles and, most surprisingly, the bone of an ancient seabird. There is also a report of the discovery of remains of a pterosaur (flying lizard) in the belly of a fish lizard. This means that the diet of ichthyosaurs was much more diverse than previously thought. Moreover, one of the species of early fish lizards discovered this year, which lived in the Triassic (about 240 million years ago), had serrated edges of the rhombic cross-section of its teeth, which indicates its ability to tear off pieces from prey. Dangerous enemies such a monster, which reached a length of 15 meters, practically did not have it. However, for unclear reasons, this branch of evolution stopped in the second half of the Cretaceous period, about 90 million years ago.

In the shallow seas of the Triassic period (240–210 million years ago), another group of reptiles flourished - the nothosaurs. In their lifestyle, they most closely resembled modern seals, spending part of their time on the shore. Nothosaurs were characterized by an elongated neck, and they swam with the help of a tail and webbed feet. Gradually, some of them replaced their paws with fins, which were used as oars, and the more powerful they were, the more the role of the tail weakened.

Nothosaurs are considered the ancestors of plesiosaurs, which the reader knows well from the legend of the monster from Loch Ness. The first plesiosaurs appeared in the mid-Triassic (240–230 million years ago), but their heyday began at the beginning of the Jurassic period, that is, about 200 million years ago.

At the same time, pliosaurs appeared. These marine reptiles were closely related, but they looked different. Representatives of both groups - a unique case among aquatic animals - moved with the help of two pairs of large paddle-shaped fins, and their movements were probably not unidirectional, but multidirectional: when the front fins moved down, the rear fins moved up. It can also be assumed that only the front fin blades were used more often - this saved more energy. The hind ones were put to work only during attacks on prey or rescue from larger predators.

Plesiosaurs are easily recognized by their very long necks. For example, in Elasmosaurus it consisted of 72 vertebrae! Scientists even know skeletons whose necks are longer than the body and tail combined. And, apparently, it was the neck that was their advantage. Even if plesiosaurs were not the most fast swimmers, but the most maneuverable. By the way, with their disappearance, long-necked animals no longer appeared in the sea. And one more interesting fact: the skeletons of some plesiosaurs were found not in marine, but in estuarine (where rivers flowed into the seas) and even freshwater sedimentary rocks. Thus, it is clear that this group did not live exclusively in the seas. For a long time, it was believed that plesiosaurs fed mainly on fish and cephalopods (belemnites and ammonites). The lizard slowly and imperceptibly swam up to the flock from below and, thanks to its extremely long neck, snatched the prey, clearly visible against the background of the light sky, before the flock rushed to its heels. But today it is obvious that the diet of these reptiles was richer. The found skeletons of plesiosaurs often contain smooth stones, probably specially swallowed by the lizard. Experts suggest that it was not ballast, as previously thought, but real millstones. The muscular section of the animal’s stomach, contracting, moved these stones, and they crushed the strong shells of mollusks and crustacean shells that had fallen into the womb of the plesiosaur. Skeletons of plesiosaurs with remains of bottom invertebrates indicate that in addition to species that specialized in hunting in the water column, there were also those that preferred to swim near the surface and collect prey from the bottom. It is also possible that some plesiosaurs could switch from one type of food to another depending on its availability, because a long neck is an excellent “fishing rod” with which it was possible to “catch” a wide variety of prey. It is worth adding that the neck of these predators was a rather rigid structure, and they could not sharply bend or lift it out of the water. This, by the way, casts doubt on many stories about the Loch Ness monster, when eyewitnesses report that they saw exactly long neck sticking out of the water. The largest of the plesiosaurs is the New Zealand Mauisaurus, which reached 20 meters in length, almost half of which was a giant neck.

The first pliosaurs, which lived in the late Triassic and early Jurassic periods (about 205 million years ago), closely resembled their plesiosaur relatives, initially misleading paleontologists. Their heads were relatively small, and their necks were quite long. Nevertheless, by the middle of the Jurassic period, the differences became very significant: the main trend in their evolution was an increase in the size of the head and the power of the jaws. The neck, accordingly, became short. And if plesiosaurs hunted mainly for fish and cephalopods, then adult pliosaurs chased other marine reptiles, including plesiosaurs. By the way, they didn’t disdain carrion either.

The largest of the first pliosaurs was the seven-meter Romaleosaurus, but its size, including the size of its meter-long jaws, pales in comparison with the monsters that appeared later. The oceans of the second half of the Jurassic period (160 million years ago) were ruled by Liopleurodons - monsters that may have reached 12 meters in length. Later, in the Cretaceous period (100–90 million years ago), colossi of similar sizes lived - Kronosaurus and Brachauchenius. However, the largest pliosaurs were the Late Jurassic period.

Liopleurodons, which inhabited the depths of the sea 160 million years ago, could move quickly with the help of large flippers, which they flapped like wings.

Even more?!

Recently, paleontologists have been incredibly lucky with sensational finds. So, two years ago, a Norwegian expedition led by Dr. Jorn Hurum extracted from permafrost on the island of Spitsbergen, fragments of the skeleton of a giant pliosaur. Its length was calculated from one of the skull bones. It turned out - 15 meters! And last year, in the Jurassic sediments of Dorset County in England, scientists had another success. On one of the beaches of Weymouth Bay, local fossil collector Kevin Sheehan dug up an almost completely preserved huge skull measuring 2 meters 40 centimeters! The length of this sea ​​dragon"could be as much as 16 meters! Almost the same length was the juvenile pliosaur found in 2002 in Mexico and named the Monster of Aramberri.

But that's not all. The Natural History Museum at Oxford University houses a gigantic lower jaw of a macromerus pliosaur measuring 2 meters 87 centimeters! The bone is damaged, and it is believed that its total length was no less than three meters. Thus, its owner could reach 18 meters. Truly imperial sizes.

But pliosaurs were not just huge, they were real monsters. If anyone posed a threat to them, it was themselves. Yes, the huge, whale-like Shonisaurus ichthyosaur and the long-necked Mauisaurus plesiosaur were longer. But the colossal pliosaur predators were ideal “killing machines” and had no equal. Three-meter fins quickly carried the monster towards the target. Powerful jaws with a palisade of huge teeth the size of bananas crushed bones and tore the flesh of victims, regardless of their size. They were truly invincible, and if anyone can be compared with them in power, it was the fossil megalodon shark. Tyrannosaurus rex next to giant pliosaurs looks like a pony in front of a Dutch draft horse. Taking a modern crocodile for comparison, paleontologists calculated the pressure that the huge pliosaur’s jaws developed at the time of the bite: it turned out to be about 15 tons. Scientists got an idea of ​​the power and appetite of the eleven-meter Kronosaurus, who lived 100 million years ago, by “looking” into its belly. There they found the bones of a plesiosaur.

Throughout the Jurassic and much of the Cretaceous period, plesiosaurs and pliosaurs were the dominant ocean predators, although it should not be forgotten that there were always sharks nearby. One way or another, large pliosaurs went extinct about 90 million years ago for unclear reasons. However, as you know, a holy place is never empty. They were replaced in the seas of the late Cretaceous by giants that could compete with the most powerful of the pliosaurs. We are talking about mosasaurs.

Mosasaurus to mosasaurus - lunch

The group of mosasaurs, which replaced and perhaps supplanted the pliosaurs and plesiosaurs, arose from an evolutionary branch close to monitor lizards and snakes. In mosasaurs that completely switched to life in water and became viviparous, their paws were replaced by fins, but the main mover was a long, flattened tail, and in some species it ended in a fin like a shark’s. It can be noted that, judging by the pathological changes found in the fossilized bones, some mosasaurs were able to dive deeply and, like all extreme divers, suffered from the consequences of such dives. Some species of mosasaurs fed on benthic organisms, crushing mollusk shells with short, wide teeth with rounded tops. However, the conical and slightly bent back terrible teeth of most species leave no doubt about food preferences their owners. They hunted fish, including sharks, and cephalopods, crushed turtle shells, swallowed seabirds and even flying lizards, tore apart other marine reptiles and each other. Thus, half-digested plesiosaur bones were found inside a nine-meter-long tylosaur.

The design of the skull of mosasaurs allowed them to swallow even very large prey whole: like snakes, their lower jaw was equipped with additional joints, and some bones of the skull were articulated movably. As a result, the open mouth was truly monstrous in size. Moreover, two additional rows of teeth grew on the roof of the mouth, making it possible to hold prey more firmly. However, we should not forget that mosasaurs were also hunted. The five-meter-long Tylosaurus found by paleontologists had a crushed skull. The only one who could do this was another, larger mosasaurus.

Over 20 million years, mosasaurs rapidly evolved, giving rise to giants comparable in mass and size to monsters from other groups of marine reptiles. Towards the end of the Cretaceous period, during the next great extinction, giant sea lizards disappeared along with dinosaurs and pterosaurs. Possible causes of a new environmental disaster could be the impact of a huge meteorite and (or) increased volcanic activity.

The first to disappear, even before the Cretaceous extinction, were the pliosaurs, and somewhat later the plesiosaurs and mosasaurs. It is believed that this happened due to a violation food chains. The domino principle worked: the extinction of some massive groups of unicellular algae led to the disappearance of those who fed on them - crustaceans, and, as a consequence, fish and cephalopods. Marine reptiles were at the top of this pyramid. The extinction of mosasaurs, for example, could be a consequence of the extinction of ammonites, which formed the basis of their diet. However, there is no final clarity on this issue. For example, two other groups of predators, sharks and bony fish, which also fed on ammonites, survived the Late Cretaceous extinction event with relatively few losses.

Be that as it may, but the era sea ​​monsters ended. And only after 10 million years sea giants will appear again, but not lizards, but mammals - the descendants of the wolf-like Pakicetus, which was the first to master the shallow coastal waters. Modern whales trace their ancestry from him. However, that's another story. Our magazine talked about this in the first issue of 2010.