Ancient sea giants: a selection of the largest inhabitants of the depths. Marine reptiles Reptiles in the air
Elasmosaurs are ancient lizards of the plesiosaur order. They reigned on the planet in the Triassic period, and in the Cretaceous period they were no longer there.
The average body length of Elasmosaurus was about 15 meters. The spine was formed from a large number of flat vertebrae, of which there could be up to 150 pieces.
The evolutionary process changed the limbs of elasmosaurs and turned them into large flippers.
These dinosaurs once lived in the sea, which was once located on the site of modern Kansas.
Elasmosaurs were the most unusual creatures of the suborder. They had a very long and flexible neck ending in a small head. At the same time, the elasmosaurus had a wide mouth, and its teeth were shaped like spikes.
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In terms of the number of cervical vertebrae, these dinosaurs are certainly in first place among the rest. For example, you can compare the cervical region of a giraffe, which consists of only 7 vertebrae.
These lizards could catch the fastest fish; their long neck helped them grab agile victims.
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At times, these dinosaurs went to shallow water, lay down on the bottom and swallowed small pebbles, which helped crush food and acted as ballast. About 250 stones were found in the stomach of one lizard. After studying the stones, scientists realized that elasmosaurs traveled several thousand kilometers throughout their lives and collected stones in different parts of the coast. Most likely, the offspring of elasmosaurs, like other ichthyosaurs, were born in the sea.
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The remains of this creature were first found in 1868 by E. Kop. Bones of elasmosaurs have been found in the United States, Japan and Russia. These dinosaurs got their name due to the flat bones of the pelvic and shoulder girdle.
If you have been to the Galapagos Islands, then you have certainly encountered a marine iguana. The photo of this animal looks terrifying, but it is not without a special harsh beauty. Marine iguanas resemble dinosaurs that lived many millions of years ago. It is these animals that we want to pay special attention to in this article.
What does a marine iguana look like?
Lifestyle
Iguanas have keen eyesight and can swim and dive well. On land they have no enemies, so they allow themselves to be slow and lazy. But in the water you often have to escape from sharks, so slowness here can be disastrous. Therefore, the marine iguana adjusts its habits depending on the environment in which it is located.
Lizards' favorite pastime on land is basking in the sun. This is due to the peculiarities of the animal’s thermoregulation. The temperature of his body depends on the environment, and in order to receive enough energy for the normal process of life, it is necessary to accumulate heat and distribute it throughout the body. The marine iguana is not in danger of overheating. It releases excess heat through the skin of the belly.
Family relationships
Darwin called marine iguanas so scary the appearance of these lizards seemed to him. But in reality they are not too aggressive. To live, marine iguanas create family groups, which include one adult male and up to ten females. Juveniles stay separate, but also form groups. Sometimes several families unite into a large community.
Each male looks after his own territory. Outsiders are not allowed onto “family” lands. Seeing a stranger, the male warns about trespassing. He takes a stable position and begins to shake his head. If the intruder does not leave, a fight begins. Usually strangers enter occupied territory, having designs on the “master’s” harem, so serious battles take place.
Behavior in water
Marine iguanas rarely swim far from the shore. In water they make wave-like horizontal movements. Animals dive not for pleasure, but for food or to escape sharks. Male iguanas are bolder and stronger, they can swim longer than females. Young animals always stay in shallow water.
What else can a marine iguana surprise? Scientists have collected interesting facts related to the blood circulation of these animals. In order not to frequently rise to the surface and not to expend excess energy, the reptile saves oxygen while in water. Blood circulation slows down, only vital organs are supplied with blood. Thus, the lizard can survive under water for more than 1 hour.
What does the animal eat?
Of course, the marine iguana looks very impressive and creepy, but it is not a predator. Marine iguanas are classified as herbivorous reptiles. They eat mainly. It is for them that iguanas learned to dive. Some types of algae entwine coastal stones, and lizards carefully scrape them off.
Reproduction
Mating games are not the favorite pastime of the male iguana. He experiences attraction to his harem only once a year. During this period, the male’s scales become brighter, brown and reddish spots appear on it, which attract active females.
The fertilized female lays several eggs in the hole. Her clutch is small - 2-3 pieces. The female sprinkles warm sand on top of her treasure. Fights often occur around the laying sites, since there are few sandy areas on the Galapagos Islands; the islands are mainly composed of volcanic rock. Sometimes females destroy the clutches of their rivals, making room for their offspring.
In warm sand, the eggs mature for about four months. Then the young appear and join the parent group. The diet of young animals contains not only plant, but also animal food. Babies need this to grow.
Marine iguanas can hardly be called caring parents. They do not protect their offspring from predators. So most of the young become prey for seagulls, snakes or dogs and cats. People are trying to exterminate stray dogs in order to preserve the population of marine iguanas, but this does not help much. Unfortunately, these animals are today classified as vulnerable species.
A few words about adaptability to life
Constant contact with salt water while swimming or eating caused the sea lizard to develop special glands that relieve it of excess salt. These salt glands are connected to the lizard's nostrils.
Salt flies out when you sneeze. If nature had not taken care of creating these glands, the lifespan of lizards would have been significantly shorter, since their kidneys would not have been able to cope with excess salt. However, due to the fact that the species' habitat is limited only to the Galapagos, it is not very well studied. There is no exact information about the lifespan of these lizards.
Incredible facts
The modern ocean is home to many incredible creatures, many of which we have no idea about. You never know what lies there - in the dark, cold depths. However, none of them compares with the ancient monsters that dominated the world's oceans millions of years ago.
In this article we will tell you about lizards, carnivorous fish and predatory whales that terrorized marine life in prehistoric times.
Prehistoric world
Megalodon
Megalodon may be the most famous creature on this list, but it's hard to imagine that the school-bus-sized shark ever actually existed. Nowadays, there are many different scientific films and programs about these amazing monsters.
Contrary to popular belief, megalodons did not live at the same time as dinosaurs. They dominated the seas from 25 to 1.5 million years ago, which means they missed the last dinosaur by 40 million years. In addition, this means that the first people found these sea monsters alive.
The home of the megalodon was the warm ocean that existed until the last ice age in the early Pleistocene, and it is believed that it was this that deprived these huge sharks of food and the ability to reproduce. Perhaps in this way nature protected modern humanity from terrible predators.
Liopleurodon
If there was a water scene in the Jurassic Park movie that included some of the sea monsters of the time, Liopleurodon would definitely appear in it. Although scientists argue about the actual length of this animal (some say it was up to 15 meters), most agree that it was about 6 meters, with a fifth of the length being the pointed head of Liopleurodon.
Many people think that 6 meters is not so much, but the smallest representative of these monsters is capable of swallowing an adult. Scientists have recreated a model of Liopleurodon's fins and tested them.
During the research, they found that these prehistoric animals were not so fast, but they were not lacking in agility. They were also capable of making short, quick and sharp attacks similar to those made by modern crocodiles, which makes them even more terrifying.
Sea monsters
Basilosaurus
Despite the name and appearance, they are not reptiles, as it might seem at first glance. In fact, these are real whales (and not the most frightening ones in this world!). Basilosaurs were the predatory ancestors of modern whales and measured between 15 and 25 meters in length. It is described as a whale, somewhat resembling a snake due to its length and ability to wriggle.
It’s hard to imagine that, while swimming in the ocean, one could stumble upon a huge creature that looked like a snake, a whale and a crocodile at the same time, 20 meters long. The fear of the ocean would stick with you for a long time.
Physical evidence suggests that basilosaurs did not have the same cognitive abilities as modern whales. In addition, they did not have echolocation capabilities and could only move in two dimensions (this means that they could not actively dive or dive to great depths). Thus, this terrible predator was as stupid as a bag of prehistoric tools and would not be able to pursue you if you dived or came onto land.
Cancerscorpios
It's not surprising that the words "sea scorpion" only evoke negative emotions, but this representative of the list was the creepiest of them all. Jaekelopterus rhenaniae is a special species of crustacean scorpion that was the largest and most fearsome arthropod of its time: 2.5 meters of pure clawed terror under its shell.
Many of us are terrified of small ants or large spiders, but imagine the full spectrum of fear experienced by a person who would be unlucky enough to encounter this sea monster.
On the other hand, these creepy creatures went extinct even before the event that killed all the dinosaurs and 90% of life on Earth. Only a few species of crabs survived, which are not so scary. There is no evidence that ancient sea scorpions were poisonous, but the structure of their tails suggests that they may have been.
Read also: A huge sea monster washed up on the coast of Indonesia
Prehistoric animals
Mauisaurus
Mauisaurus was named after the ancient Maori god Maui, who, according to legend, pulled the New Zealand carcass from the ocean floor with a hook, so just from the name you can understand that this animal was huge. The Mauisaurus's neck was about 15 meters long, which is quite a lot compared to its total length of 20 meters.
His incredible neck had many vertebrae, which gave it special flexibility. Imagine a turtle without a shell with a surprisingly long neck - that’s what this creepy creature looked like.
He lived during the Cretaceous period, which meant that unfortunate creatures jumping into the water to escape velociraptors and tyrannosaurs were forced to come face to face with these sea monsters. Mauisaurs' habitats were limited to the waters of New Zealand, indicating that all inhabitants were in danger.
Dunkleosteus
Dunkleosteus was a ten-meter predatory monster. Huge sharks lived much longer than Dunkleosteus, but this did not mean that they were the best predators. Instead of teeth, dunkleosteus had bony growths, like some species of modern turtles. Scientists have calculated that their bite force was 1,500 kilograms per square centimeter, which put them on par with crocodiles and tyrannosaurs and made them one of the creatures with the strongest bite.
Based on facts about their jaw muscles, scientists concluded that Dunkleosteus could open its mouth in one fiftieth of a second, swallowing everything in its path. As the fish grew older, the single bony dental plate was replaced by a segmented one, which made it easier to obtain food and bite through the thick shells of other fish. In the arms race called the prehistoric ocean, Dunkleosteus was a real well-armored, heavy tank.
Sea monsters and monsters of the deep
Kronosaurus
Kronosaurus is another short-necked lizard, similar in appearance to Liopleurosaurus. What is noteworthy is that its true length is also known only approximately. It is believed that it reached up to 10 meters, and its teeth reached up to 30 cm in length. That is why it was named after Kronos, the king of the ancient Greek titans.
Now guess where this monster lived. If your assumption was related to Australia, then you are absolutely right. Kronosaurus's head was about 3 meters long and it was capable of swallowing an entire adult human. In addition, after this there was room inside the animal for another half.
Also, due to the fact that the flippers of kronosaurs were similar in structure to the flippers of turtles, scientists concluded that they were very distantly related and assumed that kronosaurs also went to land to lay eggs. In any case, we can be sure that no one dared to destroy the nests of these sea monsters.
Helicoprion
This shark, 4.5 meters long, had a lower jaw that was a kind of curl, strewn with teeth. She looked like a hybrid of a shark and a buzz saw, and we all know that when dangerous power tools become part of a predator at the top of the food chain, the whole world trembles.
Helicoprion's teeth were serrated, which clearly indicates the carnivory of this sea monster, but scientists still do not know for certain whether the jaw was pushed forward as in the photo, or moved slightly deeper into the mouth.
These creatures survived the Triassic mass extinction, which could indicate their high intelligence, but the reason could also be their living in the deep sea.
Prehistoric sea monsters
Melville's Leviathan
Earlier in this article we already talked about predatory whales. Melville's Leviathan is the most terrifying of them all. Imagine a huge hybrid of an orca and a sperm whale. This monster was not just a carnivore - it killed and ate other whales. It had the largest teeth of any animal known to us.
Their length sometimes reached 37 centimeters! They lived in the same oceans at the same time and ate the same food as megalodons, thus competing with the largest predatory shark of the time.
Their huge heads were equipped with the same echo-sounding devices as modern whales, making them more successful at hunting in murky waters. In case it wasn't clear to anyone from the start, this animal was named after Leviathan, the giant sea monster from the Bible and Herman Melville, who wrote the famous Moby Dick. If Moby Dick had been one of the Leviathans, he would certainly have eaten the Pequod and its entire crew.
It seemed that these toothy and big-eyed marine predators went extinct tens of millions of years ago, but there are reports that ichthyosaurs are still found in the seas and oceans. Although these ancient creatures are similar to dolphins in many ways, it is difficult to confuse them with them, because the distinctive feature of ichthyosaurs is their huge eyes.
Dolphin-like lizards-eyed
Of the marine predatory dinosaurs, we are most familiar with plesiosaurs, and this is not surprising, because the famous Nessie is classified precisely as this type of aquatic lizard. However, in the depths of the sea at one time there were other types of predatory reptiles, for example, ichthyosaurs, which inhabited the seas and oceans 175-70 million years ago. Ichthyosaurs, which look like dolphins, according to scientists, were once among the first dinosaurs to return to the water element.
Unlike the plesiosaur with its long neck, the head of the ichthyosaur, like that of fish, was integral with the body; it is not for nothing that the name of this reptile is translated as “fish lizard”. For the most part, ichthyosaurs were not large in size, their length was 3-5 meters. However, among them there were also giants, for example, in the Jurassic period, some species reached a length of 16 meters, and in the polar regions of Canada, paleontologists discovered the remains of an ichthyosaur about 23 meters long (!), which lived in the Late Triassic.
These were toothy creatures, and their teeth were replaced several times during their lives. It is especially worth stopping at the eyes of ichthyosaurs. These reptiles had very large eyes, reaching 20 cm in diameter in some species. According to scientists, this eye size suggests that ichthyosaurs hunted at night. The eyes were protected by a bone ring.
The skin of these lizards had neither scales nor horny plates; according to scientists, it was covered with mucus, which provided better gliding in the water. Although ichthyosaurs are very similar to dolphins, they had a fish-type spine that curved in a horizontal plane, so their tail, like ordinary fish, was located in a vertical plane.
What did ichthyosaurs eat? It was widely believed that they favored the extinct cephalopod belemnites, but a team of researchers led by Ben Kier from the South Australian Museum refuted this idea. Scientists have carefully examined the stomach contents of a fossilized ichthyosaur that lived 110 million years ago. It turned out that there were fish, small turtles and even a small bird in it. This study allowed us to refute the hypothesis that ichthyosaurs became extinct due to the disappearance of belemnites.
It is curious that these marine reptiles were viviparous; this feature is clearly proven by paleontological finds. Scientists have repeatedly found the fossilized remains of ichthyosaurs, in the belly of which there were skeletons of unborn cubs. Newborn ichthyosaurs were forced to immediately begin an independent life. According to scientists, as soon as they were born, they already knew how to swim perfectly and get their own food.
Mysterious “weevil whales”
Ichthyosaurs reached their greatest diversity in the Jurassic period, and became extinct at the end of the Cretaceous. Or maybe they didn’t become extinct? After all, there is the opinion of a number of scientists that the same ichthyosaurs were warm-blooded and could well adapt to changing conditions in the ocean. When these lizards that have survived to this day die or die, their remains sink to the bottom, scientists accordingly do not find them and consider ichthyosaurs extinct.
In the early 1980s, the sailor of the Soviet cargo ship A. B. Fedorov, while sailing in the Indian Ocean, observed unusual marine animals, according to his description, very similar to ichthyosaurs. An eyewitness recalled: “I saw a light brown back and a characteristic whale fountain, but... it was not a whale or a dolphin. I saw such an animal for the first and so far only time in my life. The fact that this is some kind of mutant is excluded. There were at least five of these long-faced, toothy “whales” with large saucer-like eyes. More precisely, the eyes were in the center of the saucers.”
If this observation was the only one, it could be assumed that the sailor was mistaken and mistook quite ordinary inhabitants of the ocean for unusual creatures. However, in the spring of 1978, two members of the crew of the fishing vessel V.F. Varivoda and V.I. Titov observed a very strange sea animal with a toothy mouth. Titov described it this way: “The steep, rounded back of the head rose above the water by about 1.5 meters; a white stripe stood out brightly on the upper jaw, which, gradually expanding, stretched from the end of the muzzle to the corner of the mouth and was bordered below by a narrow black stripe... In the profile of the head was cone-shaped. The height of the upper jaw at the level of the corner of the mouth was about one meter... The total length of the head was from one and a half to two meters.”
V.I. Titov told the senior researcher at the Cetacean Laboratory, Candidate of Biological Sciences A. Kuzmin, about the mysterious animal he had encountered. The scientist had known Titov for 10 years by that time, so he took his story seriously. It is curious that Titov told him that he had seen similar “weevil whales” in the Indian Ocean more than once, and such animals usually kept in a small flock of 6-7 individuals, sometimes including calves among them.
Kuzmin showed his acquaintance many photographs and drawings of various sea animals, but Titov never identified his “weevil.” But when an image of an ichthyosaur accidentally caught his eye, he said that it was very similar to the creatures he had met.
A very living fossil?
So, there are observations of trustworthy people who have seen unknown large marine animals that are very similar to ichthyosaurs that went extinct tens of millions of years ago. Why not assume that ichthyosaurs, which at one time were distributed almost everywhere in all seas and oceans, managed to survive to our time only by significantly reducing their habitat?
It should be noted that even Soviet scientists took the messages of Fedorov and Titov quite seriously; information about a meeting with a large marine animal unknown to science was published in 1979 in the journal “Knowledge is Power.” The skepticism of scientists in recent times, of course, has been greatly influenced by the discovery of lobe-finned fish, which were considered extinct long ago. If she managed to survive to this day, then why couldn’t the ichthyosaur do it?
French scientists concluded that ichthyosaurs were warm-blooded. This conclusion was made based on data on the content of the stable oxygen isotope 18 0 in the fossil remains of ichthyosaurs. It was possible to prove that the body temperature of marine reptiles was higher than the body temperature of fish that lived with them at the same time. This discovery by scientists suggests that ichthyosaurs could well have survived, especially since they did not feed on belemnites alone. It remains to be seen that more compelling evidence for the existence of these prehistoric animals will emerge. Fortunately, many sailors now have both cameras and video cameras, and we can well hope to see footage of a whole flock of big-eyed and toothy creatures from the Jurassic period frolicking in the waves.
Prepared by Andrey SIDORENKO
Dinosaurs were the dominant vertebrates that inhabited all ecosystems of planet Earth for more than 160 million years - from the Triassic period (about 230 million years ago) to the end of the Cretaceous period (about 65 million years ago). I would like to introduce you to a list of the ten most ferocious sea dinosaurs.
10. Shastasaurus
Shastasaurus is a genus of dinosaurs that lived at the end of the Triassic period (more than 200 million years ago) in the territory of modern North America and, possibly, China. His remains were discovered in California, British Columbia and the Chinese province of Guizhou. This predator is the largest marine reptile ever found on the planet. It could grow up to 21 meters in length and weigh 20 tons.
9. Dakosaurus
In ninth place in the ranking is Dakosaurus, a saltwater crocodile that lived in the late Jurassic - early Cretaceous period (more than 100.5 million years ago). It was a rather large, carnivorous animal, adapted almost exclusively to hunting large prey. It could grow up to 6 meters in length.
8. Thalassomedon
Thalassomedon is a genus of dinosaur that lived in North America about 95 million years ago. Most likely, he was the main predator of his time. Thalassomedon grew up to 12.3 m in length. The size of its flippers reached about 1.5–2 meters. The length of the skull was 47 centimeters, the length of the teeth was 5 cm. It ate fish.
7. Nothosaurus
Nothosaurus (Nothosaurus) is a sea lizard that lived 240–210 million years ago in the territory of modern Russia, Israel, China and North Africa. It reached about 4 meters in length. It had webbed limbs, with five long fingers, which could be used both for movement on land and for swimming. Probably ate fish. The complete skeleton of Nothosaurus can be seen at the Natural History Museum in Berlin.
6. Tylosaurus
In sixth place on the list of the most ferocious marine dinosaurs is Tylosaurus, a large marine predatory lizard that inhabited the oceans at the end of the Cretaceous period (about 88–78 million years ago). It was the dominant marine predator of its time. Grew up to 14 m in length. It ate fish, large predatory sharks, small mosasaurs, plesiosaurs and waterfowl.
5. Thalattoarchon
Thalattoarchon was a large marine reptile that lived more than 245 million years ago in what is now the western United States. The remains, consisting of part of the skull, spine, pelvic bones, and parts of the hind fins, were discovered in Nevada in 2010. Thalattoarchon is estimated to have been the apex predator of its time. It grew to be at least 8.6 m in length.
4. Tanystropheus
Tanystropheus is a genus of lizard-like reptiles that lived in the Middle Triassic about 230 million years ago. It grew up to 6 meters in length, and was distinguished by a very elongated and mobile neck, which reached 3.5 m. It led a predatory aquatic or semi-aquatic lifestyle, probably hunting near the shore for fish and cephalopods.
3. Liopleurodon
Liopleurodon is a genus of large carnivorous marine reptiles that lived at the turn of the Middle and Late Jurassic period (approximately 165 million to 155 million years ago). It is assumed that the largest known Liopleurodon was just over 10 m in length, but typical sizes for it range from 5 to 7 m (according to other sources 16-20 meters). Body weight is estimated at 1–1.7 tons. These apex predators likely hunted from ambush, attacking large cephalopods, ichthyosaurs, plesiosaurs, sharks, and other large animals they could catch.
2. Mosasaurus
Mosasaurus (Mosasaurus) is a genus of extinct reptiles that lived in the territory of modern Western Europe and North America during the Late Cretaceous - 70–65 million years ago. Their remains were first found in 1764 near the Meuse River. The total length of representatives of this genus ranged from 10 to 17.5 m. In appearance they resembled a mixture of fish (or whale) with a crocodile. They were in the water all the time, diving to a considerable depth. They ate fish, cephalopods, turtles and ammonites. According to some scientists, these predators are distant relatives of modern monitor lizards and iguanas.
1. Megalodon
Megalodon (Carcharocles megalodon) is an extinct species of prehistoric shark that lived throughout the oceans 28.1–3 million years ago. It is the largest known predatory fish in history. Megalodon is estimated to have reached 18 meters in length and weighed 60 tons. In body shape and behavior it was similar to a modern white shark. He hunted cetaceans and other large sea animals. It is interesting that some cryptozoologists claim that this animal could have survived to the present day, but apart from the huge teeth found (up to 15 cm in length), there is no other evidence that the shark still lives somewhere in the ocean.
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