Why did stegosaurus need plates on its back? The most “bizarre” dinosaurs The purpose of plates and tail spines

Spiny Dinosaurs: Stegosaurus

The group of spiny dinosaurs includes one of the most mysterious and amazing in appearance dinosaurs - the stegosaurus. What makes it unusual?

In North America, several unusual bone plates were found during excavations among dinosaur bones. The researchers suggested that the body of the discovered fossil animal was covered, by analogy with scaly animals, with a tight-fitting protective shell of horny scales. Therefore, it was precisely because of the presence of plates, presumably arranged like roofing tiles, that this lizard was called “stegosaurus”, which means “roof lizard”, or “lizard covered with scaly plates”. In fact, as it turned out later, on the back of the stegosaurus, from the neck to the tip of the tail, there were two rows of these unusual bone spikes or plates, loosely attached to the skin. It is still difficult to say how these plates were arranged, interspersed or in pairs one after the other.

The largest stegosaurus was found in North America: its length was about eight meters and it weighed over two tons. There were spiky spines only at the end of the tail, and plates protruded throughout the body, the largest of which was 76 centimeters high. Centurosaurus, a spiny-tailed dinosaur that lived in East Africa, the plates on the body gradually turned into prickly spines towards the tail, and Dacentrus, the fossilized remains of which are widely represented in Europe, had only spines on the body.

Scientists still have not come to a common opinion: what were the plates used for? The answer must be found in their lifestyle. Stegosaurs and other spiny dinosaurs were four-legged herbivores. They needed protection from predators and certain means to repel enemies. However, the bone plates themselves, which were relatively light and porous, were unsuitable for active protection. It is quite possible that the animals could deliberately direct some of their sharp spines at an enemy or predator. The stegosaurus's spiny tail, when it swung it, was dangerous for any opponent.

It is possible that the bone (horny) plates were covered with thin skin and penetrated by numerous blood vessels, and served to regulate body temperature.

The head, in size, was very small, especially when compared with the size of the body.

The head of spiny dinosaurs had a peculiar beak equipped with small teeth suitable for eating soft plant food in the form of leaves and young shoots. To reach high leaves and branches, animals had to stand on their hind limbs.

Spiny and armored dinosaurs had the smallest brains compared to body size. Thus, a stegosaurus the size of an elephant had a brain of only Walnut! And apparently, such a brain was quite enough for the dinosaur, serenely grazing under the protection of its formidable spines, because spiny dinosaurs existed for many millions of years. More than a century ago, American paleontologist Othniel Marsh, who first examined a complete skeleton giant dinosaur, stated with amazement: “The very small size of the head and brain indicate that the reptile was a stupid and slow animal...”. This opinion is so ingrained that even in everyday life the word “dinosaur” has become synonymous with antiquity and stupidity.

However, as it turned out, in femoral area In the spine of dinosaurs there was another, relatively large cavity for the nerve center. Apparently, as some researchers claim, this thickening of the spinal cord constituted a kind of “second brain.”

More precisely, it was the control center for the nerve pathways of the back of the body and tail. And now, in most vertebrates with long tails the spinal cord has a noticeable thickening in this place. And stegosaurs had a tail that was not only huge, longer than the entire body, but also served as a vital important function- served as a weapon of defense. In order to accurately control all the muscles of the tail during a targeted strike, a sufficiently developed nervous system at the beginning of the tail.

However, the real brain is only the one contained in the skull.

Long-necked stegosaurus found in Portugal

In Europe, Portugal, an employee of the New University of Lisbon, Octavio Matheus, managed to excavate the remains of a dinosaur previously unknown to science in the village of Miragaia near the city of Lourinho. Paleontologists extracted the skull, forelimb bones and parts of the spine. They belonged to a member of the stegosaur genus, which Matheus christened Miragaia longicollum, meaning “long-necked one from Miragaia.”

The long-necked stegosaur Miragaia longicollum, which existed 150 million years ago, had a neck twice as long as other members of the genus. Stegosaurus had spines on its tail and 17 bony plates along its spine. The brain weighed about 80 g, and the stegosaurus itself pulled 4.5 tons.

Portuguese researchers were amazed by the number of its cervical vertebrae. Stegosaurs usually have 12-13 of them. Miragai saurus has 17 of them, making it similar to Diplodocus and other sauropods.

“Traditionally, stegosaurs were depicted as animals that fed on low-growing vegetation due to their short forelimbs and necks, and small heads. We have created a description of a new stegosaur that lived in Portugal during the Upper Jurassic, which refutes this traditional version. Miragaia longicollum had at least 17 cervical vertebrae, more than sauropods known for their long necks. Our study demonstrates the ecological diversity of stegosaurs,” says the scientist.

Matheus calculated that during the life of the Miragai saur, its neck reached 1.5-1.8 m and amounted to about 30% of its body length, which is twice as long as the neck of a regular stegosaurus. Short-necked stegosaurs, such as Huayangosaurus, which lived 170 million years ago, had only nine cervical vertebrae. The long neck could have appeared as a device for attracting mates or as a result of a transition to a different type of food, as happened in giraffes.

Which translates from Latin as "covered lizards" or "roof lizards" are a genus of ornithischian herbivorous dinosaurs that existed on Earth during the breakup of the Pangea supercontinent in the Middle Jurassic (Fig. 1). Scientists find the main number of various individuals assigned to this infraorder in the deposits of the Kimmeridgian Stage, and date back to 155-145 million years ago. n.

Discovery of the infraorder "Stegosaurs"

First more or less preserved stegosaurus skeleton, namely - stegosaurus armatus, was discovered by Yale University professor Charles Marsh during excavations north of the town of Morrison in Colorado back in 1877. Title "Stegosaurus" was given to the reptile on the basis that its skeleton was covered on top with horny plates, which Marsh initially perceived as some kind of “roof”, vaguely reminiscent of the shell of a turtle, but located only on the back of the dinosaur, while the shell of turtles covers all of them whole body.

Subsequently, many varieties of stegosaurs were found on other continents of the planet, but scientists suggest that the ancestors of this infraorder are considered to be ancient ovociform archosaurs that evolved in the African part of the supercontinent. Subsequently, from there they spread to South and North America, and already in the Jurassic period they settled along Pangea, which had not yet been split in the northern part, into Eurasian territory.

Rice. 1 - Stegosaurs

In our country, from time to time, paleontologists also managed to find fragmentary parts of the skeletons of these ancient creatures. But the most complete and well-preserved remains of a stegosaurus to this day found on the territory of Russia is the skeleton of an individual found in the Krasnoyarsk Territory among coal deposits Jurassic period, dated 170-165 million years ago. n.

The vicissitudes of the description of the stegosaurus

There are several incidents associated with the description of this genus of dinosaurs.

The stegosaurus of the Middle Jurassic period was first described by the same professor of paleontology, Charles Marsh, literally in the same year in which this discovery occurred.

At first, the stegosaurus was described by him as ancient turtle, since the scientist mistook the thyroid dorsal segments for a broken shell. In that area, excavations now did not stop, and archaeologists extracted from the ground more and more remains of ancient animals, as a rule, belonging to the same species and differing only in minor deviations in the structure of certain bones. Marsh worked tirelessly, and between 1879 and 1887 he was able, with varying degrees of success, to describe as many as six species of stegosaurs, sometimes based on only a few bones of a particular individual. Finally, in 1891, it was published for the first time illustrated reconstruction of a stegosaurus, which Marsh has been working on for the past few years.

But in 1902, another equally outstanding American paleontologist, Frederick Lucas, refuted Marsh’s theory that the bone plates were a kind of underdeveloped shell for the dinosaur, which was a kind of “gable roof.” He put forward his theory that the shields, located along the spine, were directed with their tips upward, running in two rows along it from the head to the tail, ending in massive spikes. Lucas also suggested that they served as protection for the animal from flying lizards and dinosaurs that were larger than the stegosaurus in height, in other words, they protected the animal’s back from an attack from above. Less than a year later, Lucas changed his view on the arrangement of the plates. If earlier he assumed that the plates were double-rowed and in pairs, now he argued that they were arranged in a checkerboard pattern.

Another Yale University professor, Richard Lall, entered into a debate with him in 1910, arguing that the checkerboard order of the plates was caused by the displacement of the skeleton in the ground, that is, the unevenness of its occurrence in the rocks, as a result of which the shields paired with each other shifted, thereby forming “ Lucas' chess order. Participating in the first reconstruction of the stegosaurus skeleton at the Peabody Museum of Natural History, he insisted that the dinosaur's plates be arranged in pairs, in accordance with Lucas's earlier theory.

Charles Gilmore continued the argument. In 1914, he made a statement that after analyzing a number of stegosaur skeletons and their occurrence in the soil, he found no evidence that the staggered arrangement of their plates was caused by shifting rocks or any other natural causes and external factors, and that it is in fact natural.

Rice. 2 - Stegosaurus skeleton

In the end, Gilmour and Lucas prevailed in this almost half-century dispute, and subsequently, in 1924, Stegosaurus reconstruction at the Peabody Museum was changed according to their theory, which is considered justified and generally accepted to this day.

Commonly accepted description of Stegosaurus

Infraorder Stegosaurus, in fact, in addition to the well-known representatives of the same name, it has two more varieties, namely centrosaurs and hesperosaurs. But, despite the fact that they differ slightly in their internal structure, skeletal structure and longitudinal dorsal growths, in general, in appearance these individuals are almost no different from each other.

For the most part, these herbivorous ornithischian representatives of thyreophora reached 9 meters in length, 4 meters in height and weighed, on average, 2 tons. Their jaws in the front part were equipped with a powerful beak, behind which there was a row of sharp small teeth. The animals broke off branches with their beaks, ground them with their teeth, and the greenery on them into porridge. Stegosaurs walked on four limbs, but occasionally they could climb hind legs, for example, to remove leaves from high branches. At first, Marsh believed that the stegosaurus was a bipedal lizard, but later abandoned this assumption, although the dinosaur's forelimbs were indeed half as long and less developed than the hind limbs. It is possible that an offshoot of the ancient Early Triassic thyreophora, which became the progenitors of the infraorder stegosaurs, initially preferred to move on the hind limbs, which is why the forelimbs began to decrease in size. But later, for some reason, the animals again chose to stand on four legs.

Sacral thickening of stegosaurs

What is characteristic, given its impressive dimensions Stegosaurus brain weighed no more than 70 grams, which gave the right to the first discoverer of the stegosaurus skeleton, Charles Marsh, to conclude that these reptiles were extremely slow in their mental development.

But upon further study of the skeleton in the sacral part, Marsh discovered a thickening of the spinal canal, which gave reason to say that this container contained 20 times more brain tissue than the brain itself. From that moment on, theories were put forward, one more contradictory than the other. Most scientists came down to the assumption that it was this section of the spinal cord that was responsible for all the reflexes of the body, thereby greatly unloading the brain and leaving a wide space for thought processes.

Another theory was that since Stegosaurus was basically a massive and well-protected herbivore, it had absolutely nothing to think about, except that it had to constantly chew, swallow, or sometimes stand on its hind limbs in order to reach more. attractive thread. For this, it is quite possible to get by with a 5-sanimeir brain. But for defense in a battle with predators one would have to think, but this function was elevated to the category of reflex, for which the more extensive sacral brain.

Rice. 3 - Sacral thickening of Stegosaurus

But, as it turned out later, stegosaurs were not the only representatives of the animal world whose spine in this place contained a specific thickening. This anomaly was found in the spines of many sauropods, and, most importantly, in the spines of living birds, from which scientists were able to conclude that this section contained a kind of glycogen body, the purpose of which is still unknown, but it is definitely established that it is not cannot help vertebrates think. It simply supplies the animal's brain with glycogen, but there is no answer yet as to what this is for.

Purpose of plates and tail spikes

It is still not clear exactly why these ancient ornithischians needed plates. The theory put forward in early times that Stegosaurus plates served as protection when attacked from above, it did not stand up to criticism, since the horn plates were very fragile and did not in any way resemble defensive shields. It was not difficult for predators such as allosaurs to chew them, not to mention tyrannosaurs and other giant predatory theropods. In addition, in a collision with them, no special damage could be caused, since they were sometimes so blunt that they not only could not pierce the cellular, rough skin of predators, but, on the contrary, from strong blow they themselves could have been injured.

Some have suggested that predators, due to their narrow-mindedness, like real dogs, bite their teeth into everything that sticks out and into everything that is convenient to grab onto. The dorsal plates of stegosaurs had these same features. While allosaurus and other predators ruffled their plates, the animal itself, spreading its limbs wide, defended itself with its spike-shaped tail, and after defeating one or several aggressive individuals, the predators allegedly simply retreated without causing any significant damage to the stegosaurus.

Another assumption of scientists is based on the fact that stegosaurs needed plates for thermoregulation. It is possible that these porous horny formations could be completely saturated with a dense network of small blood vessels, and thus were excellent for cooling the body in extreme heat based on the principle of elephant or hare ears.

Excavations indicate that stegosaurs could defend themselves quite effectively and deliver lethal blows with their powerful spiked tail. A considerable number of the same allosaurs with holes in the body have already been found, one to one matching the size and other parameters of the tail spines of stegosaurs.

Habitats and food of stegosaurs

Scientists suggest that all ornithischians began to spread across the ancient continent of Pangea, which in the Early Triassic was still a single supercontinent, from its African territory. So, like the path to a more distant one at that time European part was closed by the ancient ocean, ancestors of stegosaurs, early thyreophores were evenly distributed throughout Africa and South America and Antarctica, between which there was no water division at that time. Then the animals moved north into the territory North America and Europe, and then settled throughout the Asian territory of Pangea. At the end of the Triassic and the beginning of the Jurassic, the separation of continents from the main part of the supercontinent began, and in the Cretaceous period this already acquired a pronounced global scale, which is why individual branches of animals subsequently evolved in their own way. In various continental parts, between which migration routes were disrupted, new varieties of stegosaurs are still being found, although they often differ from the main branch only in their size and neck length.

Rice. 4 - Stegosaurus

So, in areas where low types of vegetation flourished, reptiles did not need long necks. Here to pick the succulent leaves from the trees special labor did not amount to. But in places where more tall trees, evolution had to work hard to produce reptiles with more long neck, equipped with additional cervical vertebrae. One of these species was Miragaialongicollum, which lived in the Upper Jurassic in what is now Europe and, in particular, in Portugal, where the remains of these individuals were found. If the main species of stegosaurs number of cervical vertebrae varied from 12 to 13, then this species had as many as 17. This gives the right to say that Miragaya, having all the features of a stegosaurus, namely, horny dorsal shields and tail spines, in appearance was more similar in body structure to Diplodocus or on other sauropods.

The genus stegosaurus differed mainly in that instead of shield plates, its back along the vertebrae had two rows of long and massive spikes. In the case of centrosaurs, those spines, which in ordinary stegosaurs are located only on the tail, go along its entire body through the entire neck up to the occipital part of the head, with the only difference that closer to the neck they become slightly wider, which indicates that that earlier they most likely had the form of plates.

Rice. 5 - Kentrosaurus

(Fig. 5) reached a length of up to 5.5 m and at the same time had a relatively low height - only 1.5-2 m. In order to feed, according to scientists, it quite often had to stand on its hind legs, since the animal had a very short neck and short forelimbs. By the way, centrosaurs also had a massive spike-like formation on the shoulder blades of the forelimbs.

Hesperosaurs

Another genus stegosaurs, belonging to the family Stegosauridae. Main distinctive feature of this variety is that in this lizard the thyroid growths along the vertebrae went only in one row, and although they were extremely massive, they were located much less frequently from each other than in the “chessboard” varieties.

Hesperosaurs reached an average length of 6.5 m with a total weight of more than 3.5 tons. These species lived on the North American part of Pangea, in what is now the state of Wyoming.

Given the general diversity and number of stegosaurs in the Jurassic period, it is very strange that these ornithischians are almost never found in Cretaceous deposits. This gives reason to say that for some reason the overwhelming number of species of these animals became extinct at the boundary of the Jurassic and Cretaceous.

Stegosaurus- dinosaur Jurassic period . Stegosaurus- representative of ornithischian dinosaurs - thyreophora. Stegosaurus- the largest representative of the stegosaur group. This group of dinosaurs was named in his honor.

Stegosaurus diet:

To survive stegosaurus had to eat a large number of food daily. Since his jaws were poorly developed, and his teeth were not very well adapted for chewing food to facilitate digestion, stegosaurus swallowed stones that helped him grind the leaves in his stomach. A similar “technique” was used by other large herbivorous dinosaurs.
Modern birds, believed to be descendants of dinosaurs, also use stones for digestion..

Limbs and body structure of the stegosaurus:

Stegosaurs moved on four legs. Front legs stegosaurus were small and short compared to the powerful rear ones. All weight stegosaurus stood on its hind legs. The body had very unusual proportions due to the fact that the hind legs were much larger than the front legs, and the back arched into a huge hump.

It is known that red is the color of danger for animals. Combined with the mass of the body and the spiked tail swinging from side to side, the impression was created as impressive.
Stegosaurus could not only frighten, but also seriously or even mortally wound the attacking lizard, attacking with its tail spikes on the unprotected paws and stomach.
Besides protective functions, back plates stegosaurus served as a thermostat. In the morning, when it's still cold, stegosaurus turned its plates towards the sun and accumulated heat, like modern solar panels. In hot weather, the plates removed excess heat, like radiators in modern technology.
Also, the coloring of the plates helped stegosaurs compete with males during the mating season.

Armored dinosaurs or ankylosaurs belong to the class of reptiles, the subclass of archosaurs and the order of ornithischian dinosaurs that appeared on the planet during the Cretaceous period (end Mesozoic era) approximately 145 million years ago.

The history of archaeological discoveries cannot boast big amount 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 knots 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 advances in 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 most weakness 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.

The name "stegosaurus" means "lizard under the roof." The first researchers thought that its dorsal plates were arranged like tiles on a roof: obliquely and slightly overlapping. Subsequently, paleontologists hypothesized that they were located vertically in two rows, and this position was more likely to correspond to their function: to regulate body temperature.

The largest, but at the same time peaceful dinosaur was the stegosaurus. Stegosaurs had one very interesting feature in the structure of the ridge - there were two rows of triangular plates on it. Most likely, these plates served to protect against enemies and to regulate body temperature: under sun rays they accumulated heat, but if the body temperature became too high, then a light wind or shade was enough - and the same plates began to give off this heat.

What did a stegosaurus look like?

Stegosaurs were truly huge, they could reach 9 meters in length, and stegosaurs had long spikes on their tails (about a meter), with which they could defend themselves from predators.
Stegosaurus was a herbivore, for this reason its teeth were weak and could only chew plant foods. The head was small in comparison with the massive body.