The most "bizarre" dinosaurs. Dinosaur: Deinonychus "Terrible Claw" Deinonychus Wasn't the Fastest Dinosaur

Deinonychus or Deinonychus is a carnivorous dinosaur of the theropod suborder. The species name comes from the Latin word Deinonychus, which means "terrible claw".

Species: Deinonychus "Terrible Claw"

For the first time this amazing dinosaur was discovered in 1963 in North America in sediments dating back to the middle of the Cretaceous period. With a height of 1.5 meters and a length of 3-4 meters, this animal could not be attributed to the giants of its time. Moreover, the length of the tail was half the entire length of the animal. This tail was rigid at the back and supported the stability of the body when running. Deinonychus ran parallel to the surface of the earth.

The same flexible tail at the base helped the animal to quickly change the direction of its run. Deinonychus used it as a rudder and this allowed him to quickly change direction, preventing the victim from escaping. On the hind limbs there was one large curved claw. During the pursuit of prey, the animal could take it up.

It was a very dangerous predator, although its size was small. The body of the lizard was ideally suited for bloody hunting. Its jaws were equipped with sharp teeth.

But his main weapon was large and sharp claws, both on the front and on the hind legs. If the victim was overtaken by Deinonychus, she was doomed to death. The predator quickly, with all his strength, plunged all his claws into the body of the victim. And then, tenaciously holding the unfortunate animal with its forelimbs with sharp claws bent down, Deinonychus beat the victim with strong hind legs and at the same time dug into it with his jaws and gnawed out pieces of prey.

The stranglehold of the jaws of the predator was ensured by the structure of its skull: the lower jaw was attached to the back of the head, while it could open its mouth wide. Plus, the teeth of Deinonychus were located at an inclination into the jaw and there was no way for the victim to free himself from his grip. Even if the unfortunate creature resisted furiously, with each movement, the predator's teeth sank deeper and deeper.

Polish paleontologists came up with the name "Deinonychus", which means "terrible claw" for a reason. The reason was the sickle-shaped claw of the second finger, which grew up to 13 cm in length. He was directed upwards and the predator was ready at any moment to put him into action.

Who were the victims of Deinonychus? Apparently, these were cubs and young dinosaurs of a wide variety of species. But most often they were herbivorous lizards, for example, hypsilophodon.

The results of archaeological excavations are always interesting, and often unpredictable. However, sometimes surprise reaches such a limit that one involuntarily thinks: apparently, nature itself mocked these creatures ... Some fossil prehistoric animals had a very strange appearance, equipped with such "devices" as vaulted skulls or crescent-shaped toenails. National Geographic magazine presented a ranking of the most bizarre dinosaurs that once lived on planet Earth.

1. Amargasaurus

Prominent Feature: Double row of spines along neck and back

Period of residence: 130-125 million years ago

Found: in Argentina

This diplodocid had a very interesting feature: a row of spines up to 65 cm long each, located on the back and neck. They could form a spiked mane or be covered in skin, creating a structure like a double sail. Whatever form they took, they were very unusual adaptations, and probably played the role of the animal's social life or were used for protection - a valuable acquisition for an animal that was almost half the size of its relatives.

Amargasaurus had a thin, whip-like tail and blunt teeth adapted for plucking leaves from branches. Like other sauropods, it probably swallowed stones, or gastroliths, to aid in the digestion of food. With its spiked spine, Amargasaurus resembled Dicreosaurus, and some paleontologists separate these two species into a separate family.

2. Carnotaurus

Prominent Feature: Strong legs and small forelegs

Period of residence: 82-67 million years ago

Found: in Argentina

The developed front legs of the Carnotaurus give the impression that the beast was conceived as a perfect killing machine, but at the final stage some details were not enough. However, predatory happiness is not in the front legs - the carnotaurus instilled fear in other dinosaurs with strong jaws, long and fast hind limbs. Carnosaurus exhibits features similar to the dinosaurs of the Northern Hemisphere, such as sharp, thin, crooked teeth, characteristic of carnivorous theropods.

Its forelimbs were very short, like those of tyrannosaurs. North America and Asia. However, the carnosaurus also had individual features; it had a horn. Horns were bony outgrowths in the upper part of the skull, directed to the side and up. During life, they apparently were covered with a cornea, like the horns of modern bulls or birans.

Carnosaurus horns most likely played the role of identifying marks, but since only a few skeletons of these dinosaurs have been found, it remains unclear whether only males had horns or females too. The muzzle of the carnosaurus was very narrow, but below the horns, the skull widened sharply, so that the eyes were shifted slightly to the side. thanks to this, the carnosaurus could have had binocular vision, when the visual fields of the left and right vision intersect. A person has the same type of vision. An animal with such vision can accurately determine the distance, which makes it an excellent hunter: carnosaurs looked out for their prey and caught it with dexterity.

3. Parasaurolophus

Prominent feature: tubular comb

Period of residence: 76 million years ago

Found: in North America

Parasaurolophus is the most remarkable representative of the duck-billed dinosaurs with hollow crests. The nasal bones of his skull turned into giant long hollow tubes, which, curving, stretched behind his head. What was the purpose of such education? Paleontologists don't yet know for sure, but they think they were some kind of voice amplifiers, similar to the nasal creases on the crestless heads of hadrosaurs. With such an "instrument" the animal could make sounds like a trombone in order to attract females or challenge rivals to a duel.

According to another point of view, such pipes created air circulation in the skull and cooled the brain in the heat. The luxurious crest of a parasaurolophus could also have had another function: to work as a kind of reflector of branches whipping in the face when the lizard made its way through the thicket - note that the crest lies exactly in the notch of the spine, while the shape of the body becomes streamlined. It is possible that all these hypotheses are correct and the crest was a multifunctional structure. And if he had a signal function, then, probably, the tail of the animal also performed the same duties. The tail was broad, laterally flattened, and very much like a plank. It appears that large patches of skin on the sides of the tail were brightly colored. With its help, the parasaurolophus also, probably, challenged the enemy to a duel, or gave signs.

4. Maciakasaurus

Outstanding Feature: Amazing Teeth

Period of residence: 70-65 million years ago

Found: in Madagascar

The fossilized remains of the jaw of Masiakasaurus - a dinosaur the size of a German shepherd - were found in Madagascar in 2001. Translated from the local dialect, the name of the dinosaur is translated as "the wrong lizard."

The main feature of Masiakasaurus is not in its small size, but in specific teeth. The first tooth of the lower jaw protrudes forward at an angle of 90˚. Other teeth are straightened and arranged vertically. The teeth themselves are also unique: in the back of the jaw they are flattened and serrated, the front ones are long, almost conical, with spiky ends and tiny serrations. This testifies to a special way of obtaining food: the Masiakasaurus caught up with the victim, wounded it with its front teeth, and chewed it with its back ones.

5. Tuojiangosaurus

Prominent Feature: Shoulder spikes

Period of residence: 161-155 million years ago

Found: in China

In the best traditions of the Jurassic period, the bulky Tuojiangosaurus has a long, spiny tail and spiny plates along its back. But this dinosaur is unique, the remains of which were found in the middle of the twentieth century in China, thanks to the sharp conical spikes that “decorate” its shoulders. Scientists differ on the function of spines. One of the versions: the spikes protected the body of Tuojiangosaurus from attacks by Alosaurs or other predators.

6. Deinocheirus

Prominent Feature: Giant paws

Period of residence: 70 million years ago

Found: in Mongolia

Deinocheirus (translated from Greek - "terrible hand") is one of the theropods, a predatory dinosaur. Anatomically, Deinocherus probably looked like a modern ostrich, but scientists do not know for sure what the body of this predator with huge arms looked like. Each of the Deinocheirus paws found extends 2.4 m. Such anatomy was especially useful during hunting. It is assumed that thanks to its clawed paws, Deinocheirus could climb trees.

7. Dracorex

Prominent feature: sharp head

Period of residence: 67-65 million years ago

Found: in North America

"Dracorex" is Latin for "king of dragons". His skull, covered with spikes and sharp protrusions, really has a royally menacing look. However, its owner himself, most likely, did not resemble a fire-breathing monster, but a wild pig.

8 Epidendrosaurus

Prominent feature: very long finger

Period of residence: 160 million years ago

Found: in China

The title of the smallest among the most bizarre dinosaurs belongs to the tiny epidendrosaurus, a representative of theropods the size of a sparrow. However, this little creature had prominent forelimbs. Epidendrosaurus was described in 2002 by paleontologists from the Chinese Academy of Sciences. This is the smallest dinosaur known to science, although scientists cannot say for sure whether the imprints of the bones on the stone belong to a young or an adult. But the object of greatest interest to experts is the function of the limbs of Epidendrosaurus. According to a common version, the epidendrosaurus used its long fingers to search for insect larvae in the trees.

9. Styracosaurus

Prominent feature: horned collar

Period of residence: 75 million years ago

Found: in North America

Styracosaurus is a herbivorous dinosaur that made this list thanks to its amazing collar. The collar of the Styracosaurus is adorned with six long, pointed spines. In addition, the dinosaur is armed with a 60 cm long horn. No predators are afraid of such an animal.
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Material from National Geographic supplemented by materials and illustrations from dinopedia.ru

Materials used: http://anastgal.livejournal.com/1390092.html#cutid1

• Class: Reptilia = Reptiles or Reptiles
• Subclass: Archosauria = Archosaurs
• Superorder: Dinosauria † Owen, 1842 = Dinosaurs
• Order: Saurischia † Seeley, 1888 = Lizard-hipped dinosaurs
• Family: Dromaeosauridae † Matthew et Brown, 1922 = Dromaeosauridae
• Genus: Deinonychus Ostrom, 1969 † = Deinonychus
• Species: Deinonychus antirrhopus Ostrom, 1969 † = Deinonychus

Genus: Deinonychus = Deinonychus "Terrible Claw"

In 1963, an amazing dinosaur was found in the Lower Cretaceous rocks in the USA, which clearly cannot be considered a giant. In height, he reached only one and a half meters, although his body reached a length of 3-4 meters. At the same time, more than half of its length fell on the tail. The tail of Deinonychus in the back was quite stiff and served as a balance when running. When running, the dinosaur's body was parallel to the ground. The tail, flexible at the base, was used as a rudder, which allowed the animal to quickly change the direction of the run, cutting off the victim's escape route. On its hind legs, it had one especially large and strongly curved claw, which leaned upwards during the run.

Deinonychus, despite its relatively small size, was a very dangerous predator. Its jaws were armed with sharp teeth, and its main weapons were large and sharp claws, which were armed with both the front and rear limbs of Deinonychus. When attacking animals, Deinonychus with lightning speed, with all its strength, plunged all its claws into the body of a pre-doomed victim. Strongly hitting the victim with the claws of the hind legs and firmly holding it with long forelimbs, which ended in three fingers with sharp claws bent down, the deinonychus quickly bit into its body with its jaws. The lower jaw was attached to the back of the skull, so the pangolin could open its mouth wide, and strong muscles provided a stranglehold. And since his teeth were located in the jaws at an inclination back, the victim could no longer free himself from the death grip of Deinonychus, even if she violently pulled out, because the teeth stuck even deeper.

The sickle-shaped claw of the second finger reached 13 cm in length. Pointing upwards, he always remained sharp and ready to attack. Therefore, Polish researchers gave the name "terrible claw" to Deinonychus for its claws - this is how its name "Deinonychus" is translated.

The victims of Deinonychus were most likely young dinosaurs of various kinds, most often herbivorous - hypsilophodon and iguanodon.

Scientists suggest that the hunting habits of Deinonychus resemble a modern leopard, comparable to it in size. Like the leopard, he could take prey larger than himself. It is possible that Deinonychus hunted in packs. The unusually large cranial cavity for dinosaurs may also speak in favor of the fact that Deinonychus was capable of complex group relationships and living together in a society of its own kind.

Currently, some researchers attribute this species to the genus Velociraptor, rejecting the independence of the genus Deinonychus † = Deinonychus, considering it a member of the genus Velociraptor: V. antirhopus (Ostrom, 1969) Paul, 1988. (see genus:

Baryonyx (Baryonyx)

It's no surprise that this British dinosaur was nicknamed "the clawed one". The huge claws that grew on the fingers of his forelimbs were almost as long as a human hand!

For the first time, the remains of Baryonyx were found next to the fossilized bones of Iguanodon, another dinosaur with claws on opposing fingers. Considering the skeleton of Baryonyx, which the experts assembled from scattered pieces, one can confidently identify a number of characteristic features in the structure of its body. Such features include, for example, an oblong skull sitting on a long neck.

The body of Baryonyx was about 9 meters long, and weighed, respectively, about 2 tons. For comparison, we note that this weight is equal to the total weight of twenty-five adult men of average height and fullness.

fish-eating

The hind legs of the Baryonyx were very powerful, although the forelimbs were practically not inferior to them in strength. Some scientists even believe that Baryonyx could move on all fours, wandering along the river bank and looking for fish.

Imagine a scene like the one below. Such scenes may well have played out about 120 million years ago on that part of the earth's landmass, which is now called England. It was the early Cretaceous period, and lush greenery flourished along the banks of numerous rivers and lakes.

The carnivorous lizard Baryonyx could well find its food in the form of many small living creatures. However, there is evidence that he obtained food in such an unusual way for a dinosaur as catching fish, which can be seen in the figure.

A huge claw on the opposing tallow could be very useful specifically for fishing. The fact that Baryonyx ate fish, scientists learned by finding fish fossils in its remains.

Teeth and claws

Another feature of Baryonyx is the double (compared to other carnivorous lizards) number of teeth in its long jaws, reminiscent of crocodiles. The largest teeth were located in the anterior cavity of the mouth, as they moved towards the back, the size of the teeth decreased.

The teeth were conical, slightly serrated, an ideal shape for grasping slippery, writhing prey, such as fish or dinosaurs as small as Hypsilophodon or even a young Iguanodon.

Scientists have come to the conclusion that in Baryonyx, the claws on the hind limbs are not as huge as those on the front. Baryonyx was too heavy to stand on one hind leg and claw the other to try to strike an opponent, as a much smaller and lighter dinosaur like Deinonychus could easily do.

Yet the forelimbs of the Baryonyx were powerful enough to carry such a formidable weapon. Probably, sea fish, even the most nimble ones, had a hard time when Baryonyx went hunting!

Attack is a common strategy in the animal world. His motives are varied: they attack because of food, possession of a female, while protecting cubs or a nest. Dinosaurs were no exception, on the contrary, they became one of the most striking examples of such behavior, invented, by the way, by completely different creatures and long before them - about 570 million years ago. It was then that organisms spread on Earth that feed on animal food instead of eating dead organic matter or algae. In other words, predators. And already then there were means of hunting (various jointed appendages, spikes, "harpoons", poisonous glands) and means of protection (shells, shells). With the advent of new life forms, the adaptations for attack and defense naturally changed, their original modifications also appeared in dinosaurs: curved claws and teeth in several rows, huge horns, collars and shells. Although, by their nature, all these wonderful devices are nothing more than modified skin or skull bones. After the dinosaurs, some reptiles and mammals also tried to arm themselves and defend themselves in a similar way, but they were all far from the Mesozoic lizards. Now on Earth, only turtles and crocodiles are content with a modest share of the terrifying equipment that the dinosaurs owned.

Deadly weapon

Predators are those animals that kill their own kind for food. Such an action requires special behavioral qualities and external devices that allow you to track down, catch up with prey and attack it. Among the dinosaurs, predation was carried out by animal-footed lizards - theropods. The dinosaurs of this group moved on two legs, while their forelimbs were reduced to small appendages. The hind legs, equipped with powerful muscles, allowed the animals to develop decent speed. According to calculations, the Tyrannosaurus rex - the most studied predator - could move at a speed of 30 km / h, which is quite a lot for a 7-ton creature. But, of course, this figure is much inferior to the speed of modern large predators, such as a tiger, sometimes reaching 80 km / h. Small and agile dinosaurs won in terms of speed. It is estimated that a 3-kilogram Compsognathus (lived in Europe 150 million years ago) could run at a maximum speed of 64 km/h.

Since the front paws of predatory dinosaurs practically turned out to be inoperative, their teeth served as their main weapon of attack. They really reached terrifying sizes and shapes in some theropods. A typical example is the mouth of a tyrannosaurus rex, studded with six dozen sharp teeth of various sizes, among which 30-centimeter "daggers" stood out. All teeth had a sawtooth notch along the rear edge and bent back, which made it possible to hold the victim and tear it to pieces. Scientists find T. rex bite marks on the bones of other animals. For example, about 80 marks are present on the pelvic bones of the herbivorous Triceratops, which clearly indicates his murder. When studying one of the tyrannosaurs, bite marks were found on its cranial bones, and a tooth belonging to a representative of the same species was found in its cervical vertebra. Is this about a fight between two tyrannosaurs? Yes, they could have mated for food or a female. Although the latter is unlikely, as it suggests the presence of developed sexual behavior, and dinosaurs are unlikely to have had such. Rather, it can be assumed that tyrannosaurs practiced cannibalism during the famine season.

Allosaurus, which lived before Tyrannosaurus Rex, could prey on giant diplodocus and apatosaurus. This is confirmed by the tail vertebrae of the Apatosaurus found in the US state of Wyoming with deep marks from the teeth of the Allosaurus, and one 15-cm Allosaurus tooth, as in the previous example, was completely stuck in the tail of the enemy. Apparently, he was knocked out in a fight between lizards.

Another terrible weapon of attack - sharp saber-shaped claws appeared in small predatory dinosaurs not immediately, but only in the Cretaceous period (145-65 million years ago). A sickle-shaped claw on the front paws had a small dinosaur Baryonyx (Baryonyx) - a "heavy claw" that lived on the territory of modern England 130 million years ago. The claws on the hind legs, one on each, were armed with a Velociraptor (Velociraptor) - a "swift hunter", a little less than two meters long. A similar 3-meter Deinonychus (Deinonychus), a “terrible claw”, had in its arsenal three sharp claws on its front paws and one saber-shaped claw 13 centimeters long on its hind legs. This long claw was movable and folded back while running. Deinonychus hunted young herbivorous dinosaurs like hypsilophodon and iguanodon, they caught up with the victim, jumped on her back with a run or clung to her side, immediately plunging her saber-shaped claw into the victim's belly.

The details of exactly how predatory dinosaurs used teeth and claws, and the list of their victims are mainly theoretical generalizations, while direct evidence (that is, finds) is extremely small, and even those allow for various interpretations. As, for example, the most famous find of two skeletons of interlocked pangolins - a herbivorous protoceratops and a predatory velociraptor, made in 1971 in the Gobi Desert by scientists of the Soviet-Mongolian paleontological expedition. It would seem that everything is obvious: both dinosaurs received heavy injuries in the fight, and they did not have the strength to open their jaws and run away when the dust storm began. And so the opponents died in each other's arms. However, in paleontology, one and the same fact can often be interpreted in different ways. No, there was no fight, opponents say, but just a bubbling water stream fancifully connected two dead animals and buried them locked under a layer of sand and silt.

Bodily adaptations, such as teeth or claws, certainly served as the main tools of a predator, but they turned out to be powerless in front of animals of comparable sizes. To cope with large dinosaurs, which also grazed in herds, additional tricks were needed. The researchers believe that for the sake of efficiency, some predators could have mastered collective hunting, as do lions and wolves. True, hunting in a pack has both pros and cons: on the one hand, it is easier to deal with the victim, on the other hand, each hunter gets less food. There is evidence of a group attack even in large dinosaurs: for example, the bones of seven Mapusaurus, found during excavations in Argentina, lay nearby. The researchers found that these dinosaurs died at the same time and may have been members of a pack that hunted together. Technically, there is nothing unbelievable in the fact that several Mapusaurus flunked a 40-meter Argentinosaurus. Similar collective burials are also known for coelophysis. It is believed that two or three of the giganotosaurs hunted. Although, on the other hand, the discovery of several skeletons of predators that died at the same time only indirectly indicates that this is a flock. The common place of their death can be explained by another fact, for example, the animals, exhausted by the heat, came to a dry watering place.

Intelligence is the main weapon of a predator

It is not enough to have teeth and claws, they still need to be skillfully used, and this is impossible without intelligence. After all, the lifestyle of a hunter implies the need to actively move in order to track down and pursue the victim, to anticipate its maneuvers. So the intellect and sense organs of predatory lizards were more developed than those of those who led a peaceful existence. And the higher the intelligence, the larger the brain size, and dinosaurs were no exception to this rule. Fossil skulls show that the brains of theropods were clearly larger than those of sauropods, gigantic herbivorous dinosaurs with long necks and small heads. Velociraptor and Deinonychus had large brains, and the absolute champion in terms of brain size was Stenonichosaurus: its brain was six times larger than that of a modern reptile of the corresponding size. In addition, stenonychosaurs had very large eyes and presumably binocular vision, similar to birds and humans. With this type of vision, the animal does not see a separate picture with each eye, but an area of ​​intersection of images received from both eyes. This allows him to move exactly to the intended target. Undoubtedly, this ability - innovative for the fauna of that time - helped Stenonychosaurus to more effectively pursue prey. Modern technologies have made it possible to draw some conclusions about the sense organs of carnivorous dinosaurs. Sergey Savelyev of the Institute of Human Morphology of the Russian Academy of Medical Sciences and Vladimir Alifanov of the Paleontological Institute of the Russian Academy of Sciences made a silicone cast of the brain over the brain cavity of a Tarbosaurus using its entire skull and compared it with the brains of birds and modern reptiles. It turned out that Tarbosaurus had large olfactory bulbs, well-developed olfactory tracts, and good hearing. But with the visual system, everything turned out differently - it was not so developed. It turns out that Tarbosaurus relied more on scent than on sight in search of prey. Why did he need it? Most likely in order to smell the smell of rotting meat from afar. Probably, the Tarbosaurus, and by analogy with it, other large predatory dinosaurs did not lead a completely predatory lifestyle - they did not neglect to eat carrion. In support of this conclusion, scientists also pay attention to the huge size of the lizards - such giants as tarbosaurus and tyrannosaurus could not always feed themselves by hunting, most likely they had to be content with what came under their feet. There is a kind of compromise version of predation: the animal hunts under a successful set of circumstances, for example, when the prey is very close and you can quickly run up to it to grab it; when she is sick and cannot escape, or the victim is a cub. In addition to these compromises, the predator fed on more readily available food, the search for which did not require large expenditures of energy.

Armor is strong

The prey, on which predatory dinosaurs “sharpened” their dagger teeth, was a very diverse spectacle: all kinds of herbivorous species, as well as those animals that ate fish, did not disdain lizards and arthropods. At present, the division of dinosaurs into carnivores and herbivores is generally rather arbitrary, most of them should rather be considered omnivores. The difference between active and passive animals is much more clearly expressed, because it was the latter that most often became the prey of the former. Dinosaurs that led a passive lifestyle, that is, they did not know how to run and hunt, were probably the most amazing creatures that ever lived on Earth. Many of them were simply overwhelmed by their size. As, for example, gigantic sauropods - diplodocus, brachiosaurus, brontosaurus - reached 40 meters in length and weighed tens of tons. It is not at all easy to kill such people, not a single predator of that time could compare with them in size. It turns out that the very size of the body of sauropods served them as a kind of protection. Allosaurs and ceratosaurus, which lived near diplodocus, were unlikely to hunt adults one by one. Most likely, predators followed the herd and waited for an old individual or a cub to fight off it. It was possible to overwhelm an adult diplodocus or a brontosaurus only by the efforts of several large predators.

Representatives of ornithischian dinosaurs - stegosaurs, ankylosaurs, horned dinosaurs were not as huge as sauropods, but outwardly very unusual. Their spikes, horns, outgrowths and shells looked like powerful protective armor. For example, stegosaurs had bone plates on their backs that extended from the vertebrae. On the back of the most famous species, the stegosaurus itself, bone plates were arranged alternately in two rows, which looked very impressive. But did they provide protection from predator teeth? Most scientists believe that the plates are unreliable as a means of protection: they are easy to break and they left the sides of the reptile open. Most likely, the plates served for thermoregulation of the individual: the skin that covered them was probably penetrated by a rich network of blood vessels, which allowed the lizard to heat up faster in the morning sun and start moving when the predators were still sleeping. But recent studies cast doubt on this version: if there were blood vessels, they were located in such a way that they could not effectively remove excess heat. It is possible that the dorsal plates served as species insignia, like the bright color of the plumage of birds, but this is not completely certain either. Why, for example, one of the stegosaurs - the "prickly lizard" Kentrosaurus (Kentrosaurus), found in Africa, has narrow and sharp plates on its back and a long spike on the sides on each side? In addition, stegosaurus had four powerful spikes on its tail, which they could well use to repel attacks from predators.

Ankylosaurs were wearing real protective armor, having mastered the vast territories of the ancient Earth - from North America to Antarctica. Their bodies were completely covered with shells of ringed bone shields encircling the back, which provided passive protection. In some species, the shields were fused, like in turtles. The shields on the shell of the ankylosaurus (Ankylosaurus) were completely dotted with bumps and spikes, so that the lizard looked like a huge bump. Such protection had its costs: armored animals were clumsy and slow, moving at a speed of no more than 3 km / h. Did the shell protect them from predators? Probably yes. Ankylosaurus became vulnerable only if it turned upside down with its belly devoid of a shell. But to do this with him was beyond the power of even a large hunter. In addition, the ankylosaurus was able to actively defend itself with a tail with a heavy bone mace, inflicting powerful blows on the enemy with it.

Herbivorous lizards from the group of ceratopsians, squat four-legged animals with a large head, acquired a horn on their muzzle. For the first time, their skeletons with impressive bone horns protruding directly from the skull were discovered back in 1872, and subsequent finds showed that at the end of the dinosaur era, “horned lizards” reached a wide variety. On the neck, ceratopsians wore a bone "collar" of fused skull bones, and the end of their muzzle looked like a beak. North American horned lizards, Triceratops (Triceratops), wore three horns: one on the nose, like a rhinoceros, and two, a meter long, sticking out above the eyes. Like modern horned animals (deer, rhinos), dinosaur horns played a primary role in sexual selection: whoever has more horns wins the best females and gets more viable offspring. In addition, Triceratops could actively defend themselves against predators with their horns: threaten, brush them off, beat the enemy from below, ripping open the belly, which, by the way, was open in bipedal theropods. Depending on the situation, the horns may have also been used as an attack weapon - to sort things out between rivals of the same species, for example, during mating fights.

The bone collars of ceratopsians also served, most likely, as a sign of external distinction, like the tail feathers of a peacock. In addition, strong chewing muscles of the jaws were attached to them. But still, collars could protect the neck, although not completely, since in many species of dinosaurs they were full of holes. The skull of a torosaurus (Torosaurus), including the collar, reached a record size of 2.6 meters, and it had several large "windows". On the other hand, the Styracosaurus found in Canada had an intact collar and was equipped with six long, sharp spines. Paleontologists believe that such good protection deterred predators from encounters with styracosaurs.

In November 2007, Canadian paleontologists dug up the world's largest horned dinosaur, 9.75 meters long, in Horseshoe Canyon in Alberta, Canada. It was identified as the ancestor of Triceratops and named Eotriceratops xerinsularis. The length of the skull of Eothriceratops was about three meters, almost like a car. Members of the expedition with great difficulty lifted it up the slope. Like Triceratops, Eotriceratops was armed with two supraorbital horns one and a half meters long and a smaller pyramidal horn on its nose. He also had a bone collar with spikes around the edges.

Dinosaurs died out 65 million years ago, and mammals took over their habitat and dominant position on land. There is much in common between them, in particular, mammals use the same devices for attack and defense as dinosaurs. Lions and tigers, as well as Mesozoic theropods, are distinguished by a muscular physique, sharp teeth and claws. And porcupines, hedgehogs and armadillos acquired shells and spines, that is, passive protection, like stegosaurs and ankylosaurs. Horns have not lost their relevance as a means of defense - they are used by rhinos, buffaloes and elks. Where does this similarity come from? We cannot say that mammals inherited all this from dinosaurs, since both groups of animals are not directly related. Biologists have another explanation: a largely similar habitat, as well as common features of the anatomical structure, close sizes of individuals led to the fact that mammals developed the same behavioral strategies as dinosaurs.

Illustrations by Olga Orekhova-Sokolova