Armored dinosaurs, or ankylosaurs
Armored dinosaurs, or ankylosaurs, which appeared only in the Cretaceous period, were even better protected from predators than stegosaurs Jurassic period. These squat, four-legged herbivores were covered from head to tail with a strong armor of bony plates, on top of which was tough corneal skin. In addition, their sides and tail were usually studded with powerful thorns or prickles. In some species, the tail ended with a huge club made of bones, which could be used to strike. When such an animal was attacked predatory dinosaur, it pressed itself to the ground, hoping that its terrifying shell would scare away the enemy. But if the attacker managed to grab the unprotected abdominal part, then the animal had nothing to hope for.
To date, 30 species of armored dinosaurs are already known. Most of them lived at the end Cretaceous period. And their ancestor, Scelidosaurus (a dismembered lizard), appeared 100 million years earlier. Its shell consisted of bony plates and spines, forming seven rows along the entire body. The 3.5-meter-long lizard apparently fed on fern and palm-shaped cycad plants.
Later armored dinosaurs are divided into 2 groups: slender, narrow-headed with a pointed tail (nodosaurs) and a loose armored shield, and squat, broad-headed (ankylosaurs) with a thickening at the end of the tail in the form of a club.
One of the first armored dinosaurs with a pointed tail is considered to be Acanthopholis (a bearer of spines) five meters long. A double row of short spines ran along his neck and shoulders. In Polacanthus (with spines on both sides) they were much larger. The skin of a nodosaur (knobby lizard) looks as if covered with large nodes. The sauropelta (lizard shield) was particularly massive: it weighed three tons and reached a length of seven meters. Later, at the end of the era of dinosaurs, the same giants were Paleoscincus (an ancient lizard) and Panoplosaurus (a lizard with a solid tail).
A distinctive feature of armored dinosaurs with a club-shaped tail was a much more durable, solid shell. Thus, the six-meter tall Talarur, found in Mongolia, had bone plates up to 5 cm thick. And in this group of dinosaurs, the largest species appeared in the last period of their existence: euoplocephalus (a typical armored head) and ankylosaur (a bent lizard) reached a length of 10 meters. Ossified tendons turned the back of the tail into a kind of rigid handle, thanks to which it was possible to deliver targeted blows with a powerful mace.
Dinosaurs in bulletproof vests
As is known, some types of dinosaurs, like modern crocodiles and turtles, had very strong armored shells. Most likely they served them to protect themselves from numerous enemies. The structure of some types of this armor turned out to be much more complex than previously thought. With their ingenuity, these ancient inventions of nature can compete not only with the protection of modern “armored” species of animals, but also with the achievements latest technologies in the field of weapons. Paleontologists at the University of Bonn were able to demonstrate that some elements of this layered protection are similar to modern composite materials used, for example, in bulletproof vests. Other dinosaurs went even further: their plate armor turned out to be much thinner and lighter, but protective properties, it seems, was in no way inferior to its heavier counterparts.
The most “armed” species of dinosaurs include the so-called ankylosaurs (Ankylosauria) - armored dinosaurs of the late Cretaceous period (70-65 million years ago) from the suborder ornithischians, also called “tank reptiles”, “armored dinosaurs” or “armored dinosaurs”. The armor of these large (6-10 m long, up to 2 m wide and weighing up to 5 tons) spindle-shaped herbivorous quadruped reptiles was so perfect that even their eyelids consisted of armored scales. Alternating rows of large and small polygonal plates formed a protective mosaic covering the entire body, there were spikes on the legs, armored rings on the tail, in some cases also with spikes, a triangular head with two large horns directed back, as if wearing a solid bone helmet - wide and very thick, leaving almost no room for the brain. The muscular, movable tail in some cases ended in a bony club, which served as a formidable weapon that allowed the herbivorous ankylosaur to defend itself from predators.
Ankylosaurs are found in the Cretaceous sediments of North America ( American states Wyoming and Montana, as well as Canada), Europe, Asia and South America. Their remains are few and far between, and their evolutionary history remains poorly understood. Most ankylosaurs were slow phytophages, living side by side with such large predators as tyrannosaurs and deiononychus, for which they served as game. The weak jaws of these ancient "tanks" and the almost absent teeth in some forms indicate feeding on the soft parts of plants. Unable to rise on two legs, the ankylosaur was content with the lower tier of vegetation. The low calorie content of such food suggests a large stomach volume, as evidenced, in particular, by the size of the body and the presence of a special enzymatic system that facilitates the digestion of fiber.
Torsten Scheyer conducted research on the armor of these dinosaurs and found that its layering is not at all identical to the structure of the skin of the same crocodile. "Its microstructure is significantly more complex, at least in some species of ankylosaurs," says Scheier. The complete "chain mail" set of dinosaurs consisted of hundreds of thousands of bone plates. Most of them were smaller than a European one-cent coin, but some were several tens of centimeters in diameter and ended in spikes. “Unlike turtle shells, the individual plates of these dinosaurs were not fused together, but rather were placed next to each other,” Scheier explains. This type of protection was quite flexible and did not break even under powerful pressure. Although modern crocodiles have a similar type of armor, the individual plates in this case have a much simpler structure.
Using a polarizing microscope, Scheier saw that the fibers in the bone armor of dinosaurs were woven in the form of peculiar “mats” that had mutual adhesion. Within each such “mat,” the fibers run parallel to each other, and the fibers of the layers above and below, respectively, are located at right angles to the adjacent layer. “The armor thus provided greater strength in all directions,” emphasizes Scheier. The structure of modern composite materials is based on the same principle - both in the manufacture of propeller blades and in the production of bulletproof vests. Of course, organics in this case are replaced by fiberglass or carbon fibers.
Armored dinosaurs or ankylosaurs belong to the class of reptiles, the subclass of archosaurs and the order of ornithischian dinosaurs, which appeared on the planet during the Cretaceous period (the end of the Mesozoic era) approximately 145 million years ago.
The history of archaeological discoveries cannot boast of a large number of finds related to armored dinosaurs. Therefore, paleontologists do not have the opportunity to thoroughly study and trace the evolutionary development of ankylosaurs. To date, science knows only 30 species of these animals, the fossilized remains of which were discovered in the Cretaceous deposits of Asia, Europe, South and North America, in particular in Canada and the USA (Wyoming and Montana).
Classification of ankylosaurs
According to the generally accepted classification, belong to the group of ankylosaurs: Scelidosaurus, Nodosaurus, Acanthopholis, Polacanthus, Sauropelta, Paleoscincus, Panoplosaurus, Talarur, Euoplocephalus and the Ankylosaurus itself.
Rice. 1 - Ankylosaurs
Scelidosaurus was the first in the chain of armored dinosaurs. It arose 100 million years earlier than the ankylosaur, reached 3.5 m in length, and fed on palm-shaped cycads and ferns. The bony plates and spines of its shell formed 7 rows along the body, so the name of the ancestor of the ankylosaur translated from Latin means "dismembered lizard".
Nodosaur possessed slim body, a narrow head, a loose, rather weak armored shield and a pointed tail. The nodosaur owes its name to the large nodes that covered the skin of the lizard.
Acanthopholis reached 5 m in length, had a sharp tip on the tail, and its shoulders and neck were dotted with rows of short spines.
Polacanthus had a similar structure and differed only in the size of the double-sided spines, which were twice as large as those of Acanthopholis.
The largest animal groups of ankylosaurs arose during the last period of their existence on Earth.
Sauropelta had strong solid armor and was particularly massive, as it weighed 3 tons and reached 7 m in length.
Paleoscincus, nicknamed "ancient lizard", And Panoplosaurus, whose name stands for "lizard with a solid tail", lived on the planet at the end of the era of dinosaurs and were considered real giants.
Talarur reached 6 m in length, had a strong solid armored shield and a tail, the tip of which resembled a mace. The remains of a dinosaur discovered in Mongolia indicate that the thickness of the bony armor plates was 5 cm.
Euoplocephalus means "typical armored head". This large ten-meter ankylosaur could easily fend for itself thanks to its powerful tail. Its back part was made of ossified tendons, which turned the limb into a kind of rigid handle with a thickening at the end, which could be used to deliver dangerous targeted blows.
The most dangerous among the listed representatives of the group were themselves ankylosaurs from the suborder ornithischians, which were also called "tank reptiles". These were squat ten-meter armored dinosaurs with a wide head, a powerful body, reliably protected by strong armor, and a tail with a dangerous tip in the form of a mace.
Features of ankylosaur armor
Like modern animals whose bodies are covered with protective shells, many species of ankylosaurs had strong armor. As in the case of living turtles and crocodiles, the armored shield protected the dinosaurs from numerous enemies and other aggressive threats. external environment. This assumption was confirmed immediately as soon as scientists began researching the structure of several types of armor. However, they never expected that the structure of ancient armored shields would turn out to be much more interesting and complex than the structure of the armor of modern animals. Moreover, prehistoric shells could compete in strength with the latest achievements in the field of military technology.
The strongest solid armor- the most striking feature that distinguished the dinosaurs of the ankylosaur group from other species (Fig. 2). During experiments, paleontologists from the University of Bonn found that prehistoric layered armor protection was similar in strength to composite materials that are currently used by the military. The research results clearly demonstrated that some elements of ancient ankylosaur shells were as strong as modern bulletproof vests. In addition, some types of dinosaurs wore thinner and lighter plate armor, which was in no way inferior to the heavy shells of their relatives in terms of protective properties.
Rice. 2 - Ankylosaurus Armor
Invaluable contribution to study of ankylosaurs contributed by the German paleontologist Thorsten Scheier, who managed to finally debunk the myth of the analogy between the layered structure of bone plates and the structure of crocodile skin. According to the scientist, ankylosaur armor was much more complex than the primitive protective layer of a crocodile. It resembled chain mail, consisting of small plates, the number of which varied within several hundred thousand. Most of these plates were no larger than a European one-cent coin, but there were also ten-centimeter-long bone plates equipped with spikes on the reptile’s body. Unlike turtle shells, the individual plates were not fused together, but were packed tightly next to each other. This structure had high plastic properties, did not experience damage under strong pressure and did not break under strong impacts.
To conduct his research, the scientist used a powerful polarizing microscope. When examining the bone plates, the device showed that the fibers in them were woven like the joints of fibers in a durable mat. That is, within each layer, the fibers ran parallel to each other, and the upper and lower levels were located at an angle of 90 degrees relative to the adjacent layer. This design ensured high strength in all directions at different angles. This observation has led to the factory production of propeller blades and protective equipment from composite material using the same principle that was used to form the armor of the ancient ankylosaur. The only difference is that instead of organics, carbon fibers or fiberglass are taken.
Distinctive features of ankylosaurs
Unlike the stegosaurs of the Jurassic period, ankylosaurs were much better protected from predators. They were covered from head to paw with armor made of tightly fitting bony plates covered with durable corneal skin, which made ankylosaurs squat and slow animals. Tail and sides of ankylosaurs equipped with thorns, sharp growths and thorns. Some species had a kind of ossified thickening at the end of their powerful tail, with which they could defend themselves and their offspring from the attacks of numerous predators.
Rice. 3 - Skeletal structure of ankylosaurs
The most warlike and well-armed species are ankylosaurs - lizards from the suborder ornithischians, who lived about 70-65 million years ago during the Late Cretaceous period. These large “armored” reptiles reached 6-10 m in length, 2 m in width and weighed about 5 tons. They were so well equipped that even their eyelids were covered with armored scales. The spindle-shaped bodies were protected by a mosaic formed from alternating rows of polygonal plates of different sizes. The legs of these reptiles had dangerous spines, and their maneuverable muscular tail was surrounded by armored rings of ossified skin with spines. Triangular ankylosaur head had two large horns curved back and was protected by a solid bone helmet 5 cm thick. Scientists suggest that, judging by the size of the skull, there was relatively little space left in the animal’s head for the brain.
Biography of ankylosaurs
Ankylosaurus was a herbivorous reptile that walked on four limbs. Its jaws were equipped with a small number of weak teeth suitable for grinding soft plant foods. Unlike long-necked herbivores, this clumsy heavyweight could not rise on its hind legs. Therefore, the ankylosaur had to be content with coarse ground grass, the lower layer of vegetation, ferns, palm-like plants and cycads. The calorie content of such food was low, so the ankylosaur must have had a huge stomach size. This is evidenced by the impressive dimensions of the reptile’s body and the presence of an enzymatic system that ensures the digestion of fiber.
Rice. 4 - Shelled dinosaur
Life of armored dinosaurs occurred during a period of climate change after the Jurassic period. The displacement of continents from their previous positions led to the fact that the change of seasons throughout the year became more and more noticeable. The climate changed from continent to continent, causing differences in the surrounding flora. In turn, the rapid increase in plant biomass led to the development of new species of herbivorous reptiles - iguanodons, triceratops and pachycephalosaurs. However, the dominant position among terrestrial animals was occupied by predatory lizard-hipped dinosaurs, for which ankylosaurs served as game. They constantly had to defend themselves from attacks by tyrannosaurs, tarbosaurs, deinonychus and spinosaurs.
The weakest point of the ankylosaur- This is the abdominal cavity. If a predator managed to get to the dinosaur’s unprotected belly, in most cases it would no longer be able to survive. Therefore, when danger arose, the ankylosaur had two options for defense: to cling to the ground, scaring off opponents with a terrifying spiky shell, or to swing its tail with a heavy tip in the form of a mace, which, if successfully hit, the dinosaur could break the attackers’ bones.
During the Cretaceous period, the dinosaurs of South America became known to science reasons increasingly larger and more ferocious than their counterparts in other parts of the globe. Giganotosaurus is an eight to ten ton, three-toed predator. By the way, its remains were discovered in close proximity to the remains of Argentinosaurus, one of the largest dinosaurs in the world... The inevitable conclusion is that Giganotosaurus was one of the few theropods capable of destroying Argentinosaurus! . For more on this scenario, see Giganotosaurus vs. Argentinosaurus – Who Wins?
Utahraptor
Utahraptor was one of the most dangerous predators in the Cretaceous period. Its adults weighed almost a ton. Utahraptors are characterized by the following features: single curved claws, similar in appearance
on a medieval sword and a Swiss army knife. Oddly enough, this predator giant size lived 50 million years before his more famous descendants, who were much smaller but much faster.
Tyrannosaurus Rex
We will never know if Tyrannosaurus Rex was stronger than giants like Albertosaurus or Alioramus. Did he hunt live prey or spend most of his time looking for carrion. In any case, there is no doubt that the T. Rex was simply the perfect killing machine when the circumstances called for it, given its weight of 5 to 8 tons, keen eyesight and huge head covered with numerous sharp teeth. True, his tiny paws - hands, from a human point of view, gave this dinosaur king a slightly comical appearance.
Spinosaurus
Spinosaurus had the same weight class as Giganotosaurus and Tyrannosaurus Rex. The North African Spinosaurus had the added evolutionary advantage of being the world's first identified dinosaur that could swim. This ten-ton predator spent its days near deep-sea rivers and ponds, snatching fish with massive crocodile-like jaws and occasionally diving like a shark to hunt small dinosaurs.
Majungasaurus
Majungasaurus, once known as Majungatol, was called a cannibal dinosaur by the press. The discovery of ancient Majungasaurus bones, which show bite marks from the teeth of Majungasaurs, is good evidence that these monotonous theropods hunted their relatives (of course, when they were very hungry, or perhaps they ate their already dead relatives). These predators were greatly feared by the smaller dinosaurs of their range.
Ankylosaurus
The armored dinosaur Ankylosaurus was a genetic relative of Stegosaurus. These dinosaurs defended their enemies equally. The Stegosaurus had a spiked sledgehammer at the end of its tail, the Ankylosaurus was equipped with a massive 45-kilogram tail hammer, appearance reminiscent of a medieval mace. Purposefully swinging such a mace could easily break the back leg of a hungry Tyrannosaurus Rex or even tear apart the jaws of an enemy. True, there is an assumption that the ankylosaur could also use its tail during intraspecific combat during the mating season.
Allosaurus
Allosaurus was a more brutal predator than the much later Tyrannosaurus Rex. Numerous specimens of this ferocious, powerful, three-ton meat eater have been discovered in the western United States. Yes, he was deadly, but not very smart.
Diplodocus
The fact is that this 30-meter huge sauropod had one thing for protection - a seven-meter thin tail, which, according to some paleontologists, it could use like a whip when striking, and the impact speed was supersonic. Apparently, thanks to this technique, Diplodocus kept such a predator as Allosaurus at bay. Of course, Diplodocus (not to mention Brasiosaurus and Apatosaurus) could simply trample the enemy with its huge, flat hind legs. By the way, filmmakers prefer to show a brighter “tail catcher” in their scripts than simple trampling.
Troodon
The feathered dinosaur Troodon weighed only about 68 kg, about the same as an adult human weighs. It is interesting to know that this predator did not have particularly sharp and terrible teeth. This theropod was distinguished by its relatively large brain, at least compared to other carnivorous dinosaurs of the Late Cretaceous of North America. There is an assumption that Troodon hunted in packs together with its relatives at night (its large eyes could see well in the dark). Troodonts could easily compete in their bloodthirstiness with T. Rex itself!
When did dinosaurs appear?
Documented evidence indicates the appearance of dinosaurs about two hundred and forty million years ago. If the history of the Earth is compressed to 1 year, considering that the birth of the Earth occurred on January 1, then the first life appeared no earlier than the end of March. The first dinosaurs would have appeared in mid-December. The first people would appear only a few hours before the end of the year.
How many animals have gone extinct?
More than 99.9 percent of the animals that have ever lived on Earth went extinct before the advent of humans.
The oldest reptile.
Unidentified (insectivorous) (1972) was found in Kentucky, USA, with an estimated age of 310,000,000 years.
Dinosaurs from the Mesozoic era.
The development of the Earth is divided into five periods of time called eras. The first two eras, Archeozoic and Proterozoic, lasted 4 billion years, that is, almost 80% of all earth history. During the Archeozoic, the formation of the Earth occurred, water and oxygen appeared. About 3.5 billion years ago, the first tiny bacteria and algae appeared. During the Proterozoic era, about 700 years ago, the first animals appeared in the sea. These were primitive invertebrate creatures, such as worms and jellyfish.
Palaeozoic began 590 million years ago and lasted 342 million years. Then the Earth was covered with swamps. Appeared during the Paleozoic large plants, fish and amphibians. Mesozoic era began 248 million years ago and lasted 183 million years. At this time, the Earth was inhabited by huge dinosaur lizards. The first mammals and birds also appeared. The Cenozoic era began 65 million years ago and continues to this day. At this time, the plants and animals that surround us today arose.
The most primitive dinosaur...
...believed to be Eoraptor lunensis. He was given this name in 1993, when his skeleton was found in the foothills of the Andes in Argentina, in rocks that are 228 million years old. The body length of this dinosaur reached 1 m. It was classified as a theropod (a predatory dinosaur from the ornithischian order).
Lifespan of dinosaurs.
Most dinosaurs lived more than a hundred years.
The largest animals.
Dinosaurs were the largest animals in the history of the Earth. One of the largest dinosaurs was the supersaurus Supersaurus. He weighed the same as 10 elephants. Reached enormous sizes herbivorous dinosaurs. Brachiosaurus and Diplodocus were especially large, up to 30 meters in length. Sauropods are representatives of a suborder of saurischian dinosaurs, distinguished by long neck with a long tail and walked on four legs. These herbivorous dinosaurs inhabited most of the land during the Jurassic and Cretaceous periods, 208-65 million years ago.
Diplodocus.
Diplodocus, who lived during the Cretaceous period, had a body length of more than 25 m; he lived in North America.
Dinosaurs had five fingers.
The land dwellers, tetrapods, were four-legged amphibians with five toes on each foot, and loved to walk along the coastal sand of ancient seas and oceans. These are the traces, 360 to 345 million years old, that were recently discovered in eastern Canada - the oldest known to date.
The most ridiculous dinosaur is the Therizinosaurus.
Therizinosaurs had bird-like legs, a snout ending in a toothless beak, and each paw had four functional toes.
The heaviest dinosaurs...
...there were probably: the titanosaur Antarctosaurus giganteus (giant Antarctic lizard), weighing 40-80 tons, the fossil remains of which were found in India and Argentina; brachiosaur Brachiosaurus altithorax (arm lizard), named for its long forelimbs (45-55 t); diplodocus Seismosaurus halli (earth-shaking lizard) and Supersaurus vivianae (both weighed more than 50 tons, and according to some estimates, was close to 100 tons). The estimated weight of the Argentine titanosaur - Argentinosaurus - was up to 100 tons. Estimates made in 1994 were based on the size of its giant vertebrae.
Armored dinosaurs.
Ankylosaurs are the most armored of the dinosaurs. Their back and head were protected by bone plates, horns and spikes. The body reached a width of 2.5 m. Distinctive feature there was a large club with which the tail ended.
The tallest dinosaur.
The tallest and largest dinosaur species with a complete skeleton preserved was the brachiosaur Brachiosaurus brancai, found in Tedaguru, Tanzania. It was discovered in Late Jurassic deposits (150 -144 million years ago). The total length of the brachiosaurus was 22.2 m; height at withers - 6 m; height with head raised - 14 m. Probably, during life, the weight of the dinosaur was 30 - 40 tons. However, the fibula of another brachiosaurus, stored in the museum, suggests that these animals were even larger.
The longest dinosaur...
... this is a brachiosaurus. Footprints suggest that the body length of the brachiosaurus Breviparopus reached 48 m. Diplodocus Seismosaurus halli, found in 1994 in the state. New Mexico, USA, reached a length of 39-52 m. These estimates are based on bone comparisons.
Iguanodon.
Iguanodon, which lived during the Cretaceous period, had a body length of about 10 m; he lived in Western Europe, North Africa, Mongolia; was a herbivore.
The smallest dinosaurs.
The smallest dinosaurs were the size of chickens. The length of the cosmognatus (trans. graceful jaw) that lived in southern Germany and southeastern France and the little-studied herbivorous fabrosaurus from pcs. Colorado, USA, from the tip of the nose to the tip of the tail was 70-75 cm. The first weighed about 3 kg, and the second - 6.8 kg.
The largest skull...
...belongs to Torosaurus. This herbivorous lizard, wearing a giant bone shield around its neck, was about 7.6 m long and weighed up to 8 tons. The length of its skull, together with the bone frill, reached 3 m, and its weight was 2 tons. It lived in the territory of the present states of Montana and Texas, USA.
Stegosaurus
Stegosaurus, which lived during the Cretaceous period, had a body length of about 9 m; was a herbivore.
The biggest marks were on...
...hadrosaur (platypus). They were discovered in 1932 in Salt Lake City, pc. Utah, USA, This large dinosaur walked on its hind legs. The length of its tracks is 136 cm and the width is 81 cm. Other reports from Colorado and Utah spoke of tracks whose width reached 95-100 cm. The width of the tracks, apparently, of the hind limbs of the largest brachiosaurs reaches 100 cm.
Triceratops.
Triceratops is a reptile that looks like a rhinoceros, lived during the Cretaceous period, had a body length of about 7 m; he lived in North America; was a herbivore.
The most toothy dinosaurs...
...these are ornithomimids. The bird-like dinosaur Pelecanimimus had more than 220 very sharp teeth.
The longest claws...
...belong to therizinosaurs found in the Nemegt Basin, Mongolia, in Late Cretaceous sediments. Their length along the outer curvature reached 91 cm (compared to 20.3 cm for Tyrannosaurus rex). This dinosaur had a fragile skull and no teeth. It probably ate termites. The second contender is Spinosaurus. In January 1983, amateur paleontologist William Walker near Dorking, c. A claw 30 cm long was found in Surrey, England. It is believed to have belonged to a Spinosaurus, the total length of which exceeded 9 m, with an estimated weight of 2 tons.
Speed of movement.
Dinosaur tracks can be used to estimate their speed. One trail, discovered in 1981 on the territory of the state. Texas, USA, suggests that a certain carnivorous dinosaur could move at a speed of 40 km/h. Some ornithomimids ran even faster. For example, the big-brained, 100-kilogram Dromiceiomimus, which lived in what is now Alberta Ave., Canada, at the end of the Cretaceous period, could probably outrun the ostrich, which reaches speeds of over 60 km/h.
- Class: Reptilia = Reptiles or Reptiles
- Subclass: Archosauria = Archosaurs
- Superorder: Dinosauria † Owen, 1842 = Dinosaurs
- Order: Ornithischia † Seeley, 1888 = Ornithischian dinosaurs
- Infraorder: Ankylosauria † Osborn, 1923 = Ankylosaurs, armored dinosaurs
- Family: Ankylosauridae † Brown, 1908 = Ankylosauridae, armored dinosaurs
- Genus: Ankylosaurus † Brown, 1908 = Ankylosaurus
Family: Ankylosauridae † Brown, 1908 = Ankylosauridae, armored dinosaurs
Ankylosaurs were large herbivorous dinosaurs that lived during the Late Cretaceous period. Its body length was 6 m and its weight was 2 tons.
The meaning of the name Ankylosaurus is translated as "Fused lizard". Ankylosaurs received their name in honor of the characteristic curvature and sharp concavity of the body ribs outward (translated from Greek, twisted, curved).
The ankylosaur walked on four legs, and its body was clad in spiked armor. The body, with thick short legs and a soft belly without armor, gradually turned into a tail, at the end of which there was a thickening. It is the bulge at the end of its thick and powerful tail that is undoubtedly the most spectacular part of the huge, massive skeleton of the ankylosaur. This mace-like thickening was approximately five times the width of a human head, and was a powerful weapon used by the ankylosaur to protect itself from enemies.
Ankylosaurus was a herbivore and never killed other animals for food. The bones of his skull were welded into a strong box-shaped structure - even for centuries 
x was a shell, and when the lizard closed its eyes in danger, they probably clicked like rifle bolts. The head of the ankylosaur ended in a kind of beak, and the teeth were located deep in the mouth and were very small and weak. They were suitable for chewing soft plant foods.
The entire body of the ankylosaur resembled pine cone, or rather half a bump - there were so many different kinds of bone outgrowths, bumps, bumps and thorns on it. The ankylosaur looked flattened on top and would even resemble a turtle, if not for its powerful tail with a heavy bony club at the end. Swinging such a mace, the dinosaur could inflict stunning blows on its enemies.
The ankylosaur lizard was something of a living tank, since the lizard's entire body was encased in extremely durable armor. Therefore, he could always try to resist the attack of even the most ferocious and hungry predators.
Head or mace ?
Some animals have learned to deceive predators - their tail part closely resembles their head. This phenomenon, which is a special case of mimicry, is called automimetism. It can be found in representatives of almost all classes of animals.
The one and a half meter tail of the ankylosaurs ended in a heavy bony thickening and resembled a club. For a long time scientists believed that this mace was a formidable weapon - a means of protecting dinosaurs from their predatory counterparts. Ankylosaurs were believed to have struck the legs of attacking predators with their tails, preventing them from approaching them. However, Australian paleontologist Tony Thulborn suggested that the tail-club was not mobile enough for this and actually had a different purpose - to imitate a head and thereby distract the predator from striking the real head. The circular movements of the mace located on the tail, reminiscent of turns of the head on a long neck, attracted the attention of the attacker and forced him to attack precisely this, less important part of the animal’s body. This is the first case of mimicry and automimetism described for dinosaurs.
Nodocephalosaurus
Nodocephalosaurus, or “Knobby Skull Lizard,” belongs to the ankylosaurs, although some researchers classify it as a separate subfamily. Nodocephalosaurus had semi-inflated and convex polygonal cranial scutes. They were symmetrically located on the head of the nodocephalosaur on both sides of the frontonasal part. Such structural features of the nodocephalosaur are similar to Asian species from the genera Saichania and Tarchia.