What did the Tyrannosaurus rex eat? Tyrannosaurus is a carnivorous dinosaur. Tyrannosaurus in popular culture

Tirex (Tyrannosaurus Rex) is by far the most popular dinosaur that lived on our planet. He became the hero of a huge number of books, films, TV shows and even video games.

For a very long time, Tirex was considered the most powerful carnivore that ever walked the Earth.

10 Little-Known Facts About Tirex

1 Tyrannosaurus Rex Was Not The Largest Carnivorous Dinosaur

Most people subconsciously believe that the North American Tyrannosaurus Rex, at 12 meters long from head to tail and weighing up to 9 tons, was the largest carnivorous dinosaur that ever walked the planet. However, an interesting fact is that in ancient times there were two types of dinosaurs that exceeded Tirex in size - this is the South American Giganotosaurus, which weighed about nine tons and grew up to 14 meters long, and the North African Spinosaurus, which weighed more than 10 tons. Unfortunately, these theropods never had the opportunity to fight among themselves, because they lived in different times and in different lands, they were separated by thousands of miles and millions of years.

2. Tirex's front legs weren't as tiny as many people think.

One Tyrannosaurus Rex anatomical feature that many people scoff at is its front legs, which appear disproportionately tiny compared to the rest of its massive body. But in fact, T. Rex's front legs were over 1 meter long and may have been capable of lifting up to 200 kg.

You will be interested to know that the most caricature-tiny front legs belong to the giant Carnotaurus. His arms were like tiny bumps.

3. Tirex had very bad breath.

Of course, most dinosaurs of the Mesozoic era did not have the ability to brush their teeth, and very few of them were denticulate. Some experts believe that the remains of rotten meat contaminated with bacteria that were constantly present between the terrible teeth made the bite of the Tirex poisonous. Such a bite would infect (and ultimately kill) the bitten victim. The problem is that this process would probably take days or weeks.

4 Female Tireks Were Bigger Than Males

We don't know for sure yet, but there is good reason to believe (based on the size of T. rex fossils found and the shape of their hips) that female T. rex outsized their males by 800 kg, a sign of sexual dimorphism.

What for? The most likely reason is that the females of the species had to lay huge eggs, which is why evolution gave females such large thighs, or perhaps females were simply more experienced hunters than males (as is the case with modern lions) and consumed more food.

5. The average lifespan of a Tirex was about 30 years.

It is difficult to infer the lifespan of dinosaurs from their fossilized remains, but based on the analysis of skeletal specimens found, paleontologists suggest that Tyrannosaurus Rex may have lived up to 30 years. Since this dinosaur was at the top of the food chain in its range, most likely its death was from old age, disease, or starvation, and not from fights with predators. Very rarely, a Tyrannosaurus rex could die from the teeth of another predator when it was too young and weak. (By the way, in parallel with T. Rex, Titanosaurs may have lived, whose weight exceeded 50 tons, their life expectancy was about 100 years!)

6. Tirex was hunting and picking up carrion

For years, paleontologists have debated whether T. Rex was a vicious killer, or a commonplace scavenger, that is, did he actively hunt, or pick up the carcasses of dinosaurs that died of old age or disease? Today, these contradictions seem rather strange, since the Tyrannosaurus Rex could use these two ways of subsistence simultaneously, like any massive predatory animal that constantly wanted to satisfy its hunger.

7 T. Rex Hatchlings May Have Feathered

We all know that dinosaurs are the progenitors of birds, and that some carnivorous dinosaurs (especially carnivores) were covered in feathers. Consequently, some paleontologists believe that all tyrannosaurs, including T. rex, must have been covered in feathers at some point in their life cycle, most likely when they first hatched from their eggs. This conclusion is supported by the discovery of feathered Asian tyrannosaurs such as Dilong and the nearly equal T. rex Yutyrannus.

8. Tyrannosaurus Rex, most of all loved to hunt triceratops

If you think that Mayweather vs. Pacquiao was the most brutal boxing fight, then you are greatly mistaken. Imagine a hungry eight-ton Tyrannosaurus Rex attacking a five-ton Triceratops! Such an unthinkable fight could certainly happen, since both of these dinosaurs lived in the late Cretaceous period in the lands of North America. Of course, the average T. Rex would prefer to deal with a sick or newly hatched Triceratops. But if he was too hungry, large individuals became his victims.

Back in 1996, a team of scientists from Stanford University, who studied the skull of this dinosaur, determined that T. Rex bit its prey with a force of 700 to 1400 kg. per square inch, the largest modern alligators bite with the same force. More detailed examination of the skulls showed that its bite force was in the range of 2,300 kilograms per square inch. (For comparison, an average adult can bite with about 80 kg per inch of force). The powerful jaws of the T. Rex could even bite through the horns of Ceratops himself!

10 Tyrannosaurus Rex Was Originally Named Manospondylus

When famed paleontologist Edward Pinker Cope unearthed the first fossilized T. Rex skeleton in 1892, he referred to it as "Manospondylus gigax - Greek" "giant thin vertebrae". After further impressive fossil searches, it was the then-president of the American Museum of Natural History, Henry Fairfield Osborn, who gave the immortal name Tyrannosaurus Rex, "king tyrant lizard."

Detachment - lizards

Family - Tyrannosaurs

Genus/Species - Tyrannosaurus rex. tyrannosaurus rex

Basic data:

DIMENSIONS

Height: 7.5 m

Length: 15.

Weight: 7 tons.

Skull length: 1.3 m

Teeth length: 30 cm

BREEDING

Mating period: not installed.

Number of eggs: probably 12 or more eggs per clutch.

Incubation period: duration unknown.

LIFESTYLE

Food: all other kinds of dinosaurs.

Dinosaur tyrannosaurus rex (see photo) is an amazing animal that lived on Earth 70 million years ago. From a height of 7.5 m, he looked predatory at other dinosaurs and confidently walked on powerful half-bent hind limbs. Tyrannosaurus was a carnivorous dinosaur.

PECULIARITIES

Our knowledge of dinosaurs is based on the conclusions obtained as a result of the study of the fossilized remains of large extinct animals: bones, tooth prints on the bones of other dinosaurs, fossilized eggs. They allow in general terms to restore the way of life of tyrannosaurs and their relatives. The first skeletons of Tyrannosaurus Rex were found at the turn of the 19th-20th centuries. in the northwestern United States. From the bones found, an almost complete skeleton of a Tyrannosaurus rex was compiled - only the end of the tail and several ribs were missing. Later finds did not add much new material. And only in 1990 in the state of Montana, paleontologists found the most complete skeleton of a Tyrannosaurus Rex to date. Today, the famous skeleton belongs to the New York Museum of Natural History. The Tyrannosaurus rex had a terrifying appearance, if you do not take into account its comically small forelimbs, with which the dinosaur could not even reach its mouth. Indeed, the front limbs of the tyrannosaurus were hidden under the skin, only short outgrowths with two thin fingers protruded from the outside. Tyrannosaurus used its forelimbs for support when it wanted to stand up. Powerful hind limbs served as a support for the entire body. During movement, this dinosaur kept its tail parallel to the ground. The Tyrannosaurus Rex was so tall that it could have peered through the third floor window of a modern panel house. Troodon, pachycephalosaurs, and maiasaurs could have been prey for Tyrannosaurus.

BREEDING

Researchers do not have data on how tyrannosaurs reproduced. Based on the fact that birds are the closest relatives of dinosaurs, it can be assumed that the tyrannosaurus, like its herbivorous relatives, laid eggs. There is no evidence that these dinosaurs exhibited parental care.

FOOD

Despite the massive body, the weight of which reached almost seven tons, the tyrannosaurus rex was surprisingly fast in pursuing prey. He ran almost as fast as an ostrich. Tyrannosaurus footprints found indicate that it moved in long jumps.

Perhaps, chasing other large dinosaurs, he developed a speed of up to 55 km / h and at the same time showed a certain dexterity. Having caught up with the prey, the tyrannosaurus rex probably reveled in the victim with its teeth and plunged the claws of its forelimbs into its body. Then he rested on the animal with his foot and with a strong movement of his head tore off a piece of meat. Other types of dinosaurs became victims of the tyrannosaurus. The ruthless predator even attacked the Triceratops dinosaur armed with dangerous horns. Usually, the tyrannosaurus rex was not able to eat the huge prey completely, so other predators ate the rest. Tyrannosaurs lived alone or in small families, but not in herds. For several days, the Tyrannosaurus devoured an amount of meat equal to its own weight.

INTERESTING INFORMATION. DO YOU KNOW WHAT...

• An adult human would barely reach the knees of a Tyrannosaurus rex, between whose legs a passenger car would fit without any problems.
• Tyrannosaurus is a huge predatory lizard, a lizard-lord (“tyranos” means lord, master, and “rex” means king).
• The first people who found the remains of dinosaurs mistook them for the bones of giant people.
• Dinosaurs, which belong to the class of reptiles, were warm-blooded animals, like modern birds and mammals. Modern reptiles, unlike them, are cold-blooded.

CHARACTERISTIC FEATURES OF THE TYRANNOSAURA REX

Scull: tall and massive, but with a small brain box.

A characteristic feature of this dinosaur was an elongated dorsal spine, in connection with which a crest developed along the back of the animal. The dinosaur's large and flat pelvic bones contributed to the even distribution of Tyrannosaurus rex's body mass.

- Places where fossils were found

WHERE AND WHEN LIVED TYRANNOSAUR

The fossil remains of this dinosaur are found in North America and Asia, where tyrannosaurs appeared at the end of the Cretaceous period, about 140 million years ago. These dinosaurs became extinct 70 million years ago.

Engels, Planet of the Dinosaurs, Tyrannosaurus Tyrannosaurus. Video (00:01:11)

Exhibition of moving fossils "Planet of the Dinosaurs" in the local history museum in Engels. "Revived" tyrannosaurus rex.

Tyrannosaurus vs Carnotaurus. Video (00:02:01)

City of dinosaurs. Tyrannosaurus Rex. Video (00:01:18)

Tyrannosaurus (lat. Tyrannosaurus - "tyrant lizard", from other Greek "tyrant" and "lizard, lizard") - a genus of carnivorous dinosaurs from the group of coelurosaurs, theropod suborder, including a single species - Tyrannosaurus rex (lat. rex " tsar"). It lived in the western part of North America, which at that time was the island of Laramidia, and was the most common of the tyrannosaurids. Tyrannosaur fossils have been found in various geological formations dating back to the Maastrichtian Stage of the Late Cretaceous, about 67–65.5 million years ago. It was one of the last lizard dinosaurs that existed before the cataclysm that ended the era of dinosaurs (the Cretaceous-Paleogene extinction).
Like other members of its family, Tyrannosaurus was a bipedal predator with a massive skull balanced by a long, heavy tail. Compared to the large and powerful hind limbs of this lizard, its front paws were quite small, but unusually powerful for its size, and had two clawed fingers. It is the largest species of its family, one of the largest representatives of theropods and one of the largest land predators in the history of the Earth.
(Wikipedia)

Tyrannosaurus rex was one of the largest land predators in the history of civilization, had excellent binocular vision and a well-developed sense of smell. With mighty sharp teeth, like giant scissors, he tore prey and crushed the bones (not very large) of herbivorous dinosaurs. Such a heavyweight was not a sprinter - he often ate carrion, and the younger generation actively pursued and caught up with prey.

For the first time, a tyrannosaurus, or rather, its skeleton, was discovered in 1902 in the United States.

The reptile moved on two legs, had tiny, short two-toed forelimbs and had huge jaws.

The word "tyrannosaurus" itself comes from two Greek words "tyrant" and "lizard".

It has not been conclusively established whether tyrannosaurs were predators or whether they fed on carrion.
Tyrannosaurs are scavengers. One of the paleontologists, American expert Jack Horner, claims that tyrannosaurs were exclusively scavengers and did not take part in hunting at all. His hypothesis is based on the following statements:
tyrannosaurs had large (relative to brain size) olfactory receptors, which suggests a well-developed sense of smell, which presumably served to locate rotting remains at great distances;
powerful teeth 18 cm long each allow crushing bones, which is required not so much for killing, but for extracting as much food as possible from what is left of the carcass, including bone marrow;
if we assume that tyrannosaurs walked, not ran (see below), and their prey moved much faster than them, then this can serve as evidence in favor of feeding on carrion.

Tyrannosaurus rex were brutal, aggressive predatory killers.

There is evidence in favor of the predatory lifestyle of the tyrannosaurus:
the eye sockets are arranged in such a way that the eyes could look forward, providing the Tyrannosaurus rex with binocular vision (allowing it to accurately judge distances), which is primarily required by a predator (although there are many exceptions);
bite marks on other animals and even other tyrannosaurs;
the comparative rarity of finds of the remains of tyrannosaurs, in any ecosystem the number of large predators is much less than their victims.

Interesting Facts:

While studying one of the tyrannosaurs, paleontologist Peter Larson discovered a healed fracture of the fibula and one vertebra, scratches on the facial bones, and a tooth of another tyrannosaurus rex embedded in the cervical vertebrae. If the assumptions are correct, then this indicates aggressive behavior of tyrannosaurs towards each other, although the motives remain unclear: whether this was competition for food/partner or an example of cannibalism.
Later studies of these wounds showed that most of them are not traumatic, but infectious in nature, or were inflicted after death.

In addition to live prey, these giants did not disdain to eat carrion.

Many scientists believe that tyrannosaurs could have had a mixed diet, like, for example, modern lions - predators, but can eat the remains of animals killed by hyenas.
The mode of movement of the tyrannosaurus rex remains a controversial issue. Some scientists are inclined to the version that they could run, reaching a speed of 40-70 km / h. Others believe that tyrannosaurs walked, not ran.
“Apparently,” writes H.G. Wells in the famous Outline of the History of Civilization, “tyrannosaurs moved like kangaroos, leaning on a massive tail and hind legs. Some scientists even suggest that the Tyrannosaurus rex moved by jumping - in this case, it must have had absolutely incredible muscles. A jumping elephant would be much less impressive. Most likely, the tyrannosaurus preyed on herbivorous reptiles - the inhabitants of the swamps. Half immersed in liquid swamp mud, he pursued his victim through the channels and lakes of swampy plains, such as the current Norfolk swamps or the Everglades swamps in Florida.
The opinion about bipedal dinosaurs - similarities of kangaroos was widespread until the middle of the 20th century. Examination of the tracks, however, showed no tail prints. All carnivorous dinosaurs kept their body horizontal when walking, the tail served as a counterweight and balancer. In general, the tyrannosaurus is close in appearance to a huge running bird.
Recent studies of proteins found while examining a fossil T. rex femur have shown dinosaurs to be closely related to birds. Tyrannosaurus is descended from small carnivorous dinosaurs of the late Jurassic era, not from carnosaurs. The currently known small ancestors of Tyrannosaurus Rex (such as the dilong from the Early Cretaceous of China) were feathered with fine, hair-like feathers. The Tyrannosaurus rex itself may not have had feathers (known impressions of the skin of the thigh of a Tyrannosaurus rex bear a pattern of polygonal scales typical of dinosaurs).

In the near future, articles about other prehistoric animals will appear on our website. Since you are here, it means that you are an inquisitive person and very, very good. Don't leave us, come back often. In the meantime - we wish you good luck in life and joyful bright days!

In The Tyrannosaurus Chronicles: The Biology and Evolution of the World's Most Notorious Carnivore, renowned tyrannosaurus specialist David Hawn gives the most complete picture of the evolution and all aspects of life of these amazing ancient reptiles and their contemporaries in the light of the latest paleontological research.

Too often, when it comes to tyrannosaurs - and any dinosaurs in general - the main focus falls on one tyrannosaurus rex. Among all dinosaurs, it is much more known to the general public, and as a result, almost every discovery of a new dinosaur (and even many non-dinosaurs) seems to be compared to it. Such is the appeal and recognizability of the "tyrant king" of the dinosaurs that it has become a media reference, whether or not it relates to any particular story.

Of course, the tyrannosaurus was a surprisingly interesting animal in its own way, but excessive attention to it as a kind of benchmark for comparison is often not justified. He was no more a typical dinosaur than aardvarks, lemurs or kangaroos are typical mammals. It was an animal with features honed by the pressure of evolutionary selection to a form quite different from most other theropods and, even to the extreme, from most other tyrannosaurs. Although the closest relatives of Tyrannosaurus in the genera Tarbosaurus and Juchantyrannus were very similar to it, it stands out among them in that it has been disproportionately studied over the decades, and because as a result we now know more about it than about any other dinosaur, tyrannosaurus has become the best model for future research. Like a fruit fly Drosophila (Drosophila melanogaster)- the central object of genetic research, smooth clawed frog (Xenopus laevis)- neurology, and a small round nematode worm (Caenorhabditis elegans)- developmental biology, so tyrannosaurus rex is a key animal for most dinosaur research. This fact has clearly contributed to its overestimation in the eyes of the public (and even in some scientific circles), but it also means that it is the most studied of all dinosaurs.

We simply know more about the Tyrannosaurus Rex than any other extinct dinosaur, and as a result, its biology is an excellent subject for discussion (and for me, fortunately, an ideal topic for writing a book).

The downside of this situation was that I had to refer to Tyrannosaurus rex much more often than I would like, simply because it is often the only member of the clade for which this particular trait or behavior has been confirmed. Other taxa are not well understood, and although some are actually quite new (such as Yutyrannus and Lythronax) and others are known from very little material (Proceratosaurus, Aviatyrannis) or both (Nanuksaurus), further research is required. much more research into the anatomy, evolution, and especially the ecology and behavior of many non-tyrannosaurine tyrannosaurs. It is likely that early forms, in part because of their relative unspecialization, can in some sense be combined with animals like small megalosaurs or allosaurs in terms of potential prey, feeding methods, etc. However, the tyrannosaurus rex is especially interesting not so much because of what kind of animal it was how it came to be, as well as the evolutionary paths that turned early tyrannosaurs into such incredible animals as albertosaurines and tyrannosaurines.

Another problem is that dinosaurs in general, and tyrannosaurus rex in particular, can give some people very strange ideas. No field of science is spared from periodically emerging eccentric concepts that can come from even talented and respected scientists, and not just "marginal" authors. Even if some contentious issues are eventually settled in academic circles, information about it does not necessarily go beyond those circles; "scientists have come to an agreement" - not as exciting news as "new scandalous discussions around the tyrannosaurus." Thus, the public often gets to hear only the beginning of the story, and much less attention is paid to further work. This, first of all, was the reason that the topic “predator or scavenger” is endlessly exaggerated, while, firstly, it was hardly worth raising it at all, and secondly, it was far from one times (most detailed by paleontologist Tom Holtz in 2008).

Some of these points have already been mentioned by me, while others have been largely omitted for the sake of clarity of presentation of the relevant chapters, but it is worth returning to them, as they usually generate confusion or have a significant impact on our understanding of these animals. I will add here that in recent years there has been a situation where the media are taking seriously such ideas that can only be called intriguing out of generosity: for example, that dinosaurs lived in water or that they evolved on other planets in parallel worlds and live and live to this day, avoiding in his space house of mass extinction. I won't delve into such fringe ideas here (they're covered in more detail on the internet), but there are serious discussions in the scientific literature about some plausible theories and it's hard to miss them. And the first - and main - of them is the problem of nanotyrannus.

Tyrannosaurus baby?

In the collections of the Cleveland Museum of Natural History, a very modest theropod skull is exhibited. This skull clearly belonged to a Tyrannosaurus rex: the broad back rapidly tapers towards the front, converging to a long but still broad muzzle with a rounded tip, and there are relatively few large teeth in the jaws.

In fact, it looks quite similar to the skull of a Tyrannosaurus rex, only less than half the size expected: it is a little over 50 cm long. meters than the size of a typical adult tyrannosaurus rex.

Originally described as a specimen of Gorgosaurus by paleontologist Charles Gilmour in 1946, this skull has been the subject of much debate over the years. Partly because it is somewhat younger than Gorgosaurus and could in fact be a contemporary of Tyrannosaurus Rex, but also because it is not a Gorgosaurus skull but some other animal.

The key question is: did it belong to a young tyrannosaurus rex, or is it still the skull of a miniature tyrannosaurus that lived next to the most famous of the dinosaurs? The second hypothesis was formally stated by Bob Bakker et al. in a 1988 paper, where they noted that some of the skull bones appear to be fused. If so, then we have an adult skull, and although the animal may have grown a little more later, it was clearly much smaller than any other North American tyrannosaurus rex from the late Cretaceous, and also deserved recognition as a species. For its small size, it was called nanotyrannus.

Since then, discussions have raged whether this animal is a representative of a separate taxon, since the fusion of some bones of the skull alone can hardly be considered a defining indicator of the maturity of an individual. The important thing is that if the skull represents a new taxon, then tyrannosaurus is not the only tyrannosaurine of its time in the Americas, and the large size gap between tyrannosaurus and the various dromaeosaurs and troodontids is at least partially filled by nanotyrannus, implying a completely different ecology for predators of this period. than previously assumed. At the same time, if the skull is from a juvenile tyrannosaurus rex, we will have an excellent opportunity to study the growth and development of animals of this species; with a very young specimen of Tarbosaurus already known, there is a huge field for studying how these animals changed with age and questions of a possible ecological separation between juveniles and adults.

Those who support the isolation of nanotyrannus as a new species point to some features in the morphology of the skull that are not observed in known specimens of tyrannosaurus rex. For example, the jaws of a nanotyrannus have several more teeth, but individual variation is always possible in this area, and it is not clear how the teeth could change as the animal grew. We already know that the proportions of the limbs and the shape of the skull changed, so that some other elements could well appear and disappear in the process of growth. However, the number of teeth in Gorgosaurus seems to have varied between ages, and the same may be true for Tyrannosaurus (even if not for Tarbosaurus), but the number of teeth in Tyrannosaurus as a whole was probably a highly variable feature. Moreover, additional analyzes, such as those performed by Thomas Carr, suggest that nanotyrannus and tyrannosaurus have common features, and the first specimen is a juvenile, not an adult.

This problem is further complicated by the presence of Jane (the name, like most others, is given in honor of the merit of a certain person, and does not indicate the sex of the individual) - a largely preserved specimen of a young tyrannosaurus, which is also attributed to either a nanotyrannus or a tyrannosaurus rex (see illustration below). Jane was clearly a juvenile, as her skeleton has many unfused bony sutures, and some histological evidence also points to a juvenile, but is it a young tyrannosaurus or a second nanotyrannus? Jane's specimen at the time of death exceeded six meters in length, and therefore, given the upcoming significant growth, it was unlikely that it was a "dwarf" animal; moreover, it was found to have more teeth than a typical adult Tyrannosaurus rex, and this supports the idea that the number of teeth decreased as it grew. Several traits unique to a T. rex are observed in Jane, also supporting the idea that she is a juvenile T. rex. However, given the similarity of Jane's skull and the Cleveland find, it can be assumed that the second is also "only" a young tyrannosaurus rex.

The skeleton of an individual named Jane, which most researchers consider a juvenile representative of a tyrannosaurus rex (for comparison, the skeleton of an adult animal is shown), but there is also a hypothesis that it belongs to a small type of tyrannosaurus rex. Note the differences in leg length and the shape of the skull and pelvis.

Hawn D. Tyrannosaurus Chronicles. - M.: Alpina non-fiction, 2017

And the last complication of the picture was a controversial specimen, recently dug up in the United States and in private hands. A small tyrannosaurus rex has been discovered alongside a ceratopsian, supposedly representing the result of a deadly fight (needless to say, most experts are very skeptical about this), and it has been hypothesized that this new specimen "solves" the nanotyrannus problem. However, although this copy is for sale, it has not been made available to scientists, so for now this theory is purely fantasy. A few not-so-good photos of an incompletely assembled specimen are not something to base judgment on, so for the time being this specimen remains an unfortunate side branch of a common problem.

There is growing evidence that both Jane and the Cleveland skull are true tyrannosaurs, based in part on comparisons with specimens of a very young Tarbosaurus from Mongolia and growth trends observed in other dinosaurs. If this assumption is correct, we have an excellent growth scale for a Tyrannosaurus rex, further supported by a small fragment of a snout preserved in Los Angeles, belonging to a very small individual, about a year old, judging by the size. In fact, all this suggests the existence of certain differences between tyrannosaurines. Even split, the skull of a small Tarbosaurus looks more like an adult, i.e. it is assumed that the animal at all ages retained approximately the same shape of the skull, it simply became larger.

Jane's skull, meanwhile, is more like that of an early Tyrannosaurus Rex or Alioramin (long and narrow, lacking a wide back); as it grew, the back wall "swollen" to form the classic shape of a Tyrannosaurus rex's skull. This indicates significant changes in the functioning of the skull and, possibly as a result, in the ecology of the animal. At this point, despite some strong counterarguments, it's better to consider nanotyrannus an invalid taxon rather than a distinct pygmy tyrannosaurus rex, however attractive the idea may seem.

Two tyrannosaurs?

The problem of nanotyrannus is just one of a series of taxonomic difficulties surrounding the question of whether T. rex was the only late Cretaceous tyrannosaurus in America, as some experts suggest that a second type of T. rex also existed. The idea for this so-called Tyrannosaurus Rex X was first conceived by paleontologist Dale Russell, although Bob Bakker gave it the nickname X. It was based primarily on the fact that some Tyrannosaurus rex specimens had a pair of small teeth on the front of the dentary rather than one, and also on the fact that the skulls of some specimens looked significantly larger than others. Based on these and other proposed differences, further researchers took up the idea and suggested that a second T. rex might be hiding among the available rex specimens.

In a sense, this would be logical: it is noteworthy that Tyrannosaurus rex, apparently, was the only large predator in its ecosystem, while two or more species of large predators were usually present in both modern mammalian ecosystems and ancient dinosaurs, those. the tyrannosaurus rex ecosystem looks a bit strange. However, the data are scarce, and the differences between the considered animals are very small. Of course, there are differences between the specimens we have, but we can expect that at least some of them are due to intraspecific variability, and even a few small persistent differences do not necessarily indicate the presence of separate species.

This problem echoes the idea that known Tyrannosaurus rex specimens have two identifiable types of constitution, designated "powerful" and "gracil" forms: i.e., one is considered to be denser, the other proportionately more fragile. Moreover, it is suggested that these two types of constitution are not simply associated with general differences in appearance, as in thick or thin people, they are allegedly linked to implicit sexual dimorphism, where one form corresponds to males and the other to females. As already mentioned, some dinosaur specimens (especially tyrannosaurs) end up with nicknames, but these nicknames are mostly random and not related to the animal's gender, so Sue is no more a female than Bucky or Stan are males. Previous ideas to distinguish between males and females based on the number or shape of bony chevrons have proven ineffective, and the only reliable way to identify a mature female is the presence of medullary bone. However, even here, its absence may indicate either that the animal was male, or that death occurred outside the breeding season, and not all specimens have been studied. (For some unknown reason, many museum curators get nervous when you offer to cut their dinosaur skeletons. - Approx. Aut.).

So, do these “morphs” exist at all, and if so, do they correlate with males and females? And which one is which? Most researchers remain highly skeptical of these ideas. The data is limited and most of the material does not overlap in terms of present skeletal parts, and there is also scatter in time and space. All specimens, separated by thousands of square kilometers and millions of years, are assigned to the same species, but theoretically they should have been representatives of very different populations. Thus, even if there is a sign that indicates the possibility of dividing specimens into two groups, how much this picture will be distorted by the errors of such data and the fact that animals almost certainly changed in size and shape in the course of evolution (the growth and variability of individuals will also cause trouble)?

All this is not said to rule out any of the hypotheses discussed, but given the inevitable limitations of such an analysis, we should be looking for much clearer and more enduring differences between the two putative groups.

We do observe subtle differences between all possible closely related species, but even so there are usually some stable and distinct anatomical features that can be used to distinguish them, and this is the basis of the morphological species concept as applied to dinosaurs. We will inevitably have to wait for additional data: new information should lead to an unambiguous interpretation of the results, and with enough fossil specimens, it may be possible to analyze a single population to eliminate many of the problems discussed above.

Research is ongoing, and although controversy still arises and is the subject of debate, in reality, it quite often leads to additional research and refinement of ideas, as well as the creation of ever better diagnostic methods and data sets that confirm or refute current points of view. Therefore, controversial ideas can be useful in stimulating new research; problems begin when such assumptions continue to cling to long after they have been debunked. The concepts discussed here are at least plausible and are advocated and debated by serious scholars, but still the ideas "on the verge of insanity" also have value. In any case, they show the inexhaustible fascination with the tyrannosaurus and the attention directed to it.

Mouth shut: they had lips. Perhaps tyrannosaurs were not as toothy as they are usually portrayed. New research suggests that their sharp pearl teeth were hidden behind the labial folds. This discovery could change the typical image of a dinosaur showing off its fanged grin.

The deadly fangs of a Cretaceous predator were covered with a rather thin layer of enamel. To avoid the destruction of the enamel and, as a result, the tooth, such a thin and fragile enamel must be constantly maintained in a moist environment. The study of modern large lizards confirms this theory: all terrestrial species, such as the Komodo dragon, have closed mouths.

Their lipless counterparts, such as crocodiles, live in water, in a humid environment, and do not need additional moisture to preserve the tooth surface. The Tyrannosaurus rex terrified all the inhabitants of the earth (not water!), And he needed lips to protect his 10-15 cm teeth and keep them in excellent combat condition.

Herd mentality: tyrannosaurs moved in packs. This is one of the reasons why you probably don't want to travel back in time to the Cretaceous period. In western Canada, scientists have discovered the remains of three tyrannosaurs moving together. And although the reasons for their death have not been established, scientists have received new information about the habits of tyrannosaurs.

The three tyrannosaurs discovered were mature specimens that had already seen life. All three knew perfectly well how to survive in their cruel world where the dinosaur ate the dinosaur. They were about 30 years old - and this is a respectable age for a tyrannosaurus rex. The skin prints were still visible, and one could even see that one of the dinosaurs had its left leg torn off. They followed each other, but kept their distance. These footprints, left 70 million years ago, are the best evidence that dinosaurs formed into herds.

Transitional age: teenage terror among tyrannosaurs. There is one version that explains why the "Canadian trio" kept their distance from each other. From a very early age, tyrannosaur cubs entered into fierce fights with each other. The remains of one of the young dinosaurs, named "Jane" (although the sex of the animal has not been determined), suggests that the dinosaur was beaten to a pulp by another young dinosaur.

A heavy blow was dealt to Jane's muzzle and upper jaw, which broke her nose. The adversary was the same age as Jane: his teeth prints match the size of Jane's teeth. At the time of her death, Jane was 12 years old, and these injuries had already healed, leaving her face forever flattened. This means that the fight happened much earlier, when both dinosaurs were even younger.

By the age of 12, Jane was already a real instrument of death: a baby compared to an adult tyrannosaurus, she reached 7 m in length and 2.5 m in height at the sacrum, and her weight was about 680 kg.

"He or she?": a gender question. Paleontologists are still struggling with the exact sex of dinosaurs. Even dinosaurs with crests, bony collars at the back of their skulls, horns, spikes, and other distinctive features are not strongly gendered. It seems that male and female dinosaurs looked the same.

However, take a look at the famous MOR 1125, also known as the "B-rex", one of the specimens of the Museum of the Rocky Mountains. An information plate near the exhibit confidently states that the remains belonged to a female.

The find of MOR 1125 was notable for the fact that soft tissue was preserved in the femur of this dinosaur. Mary Schweitzer, a paleontologist at the University of North Carolina, made a discovery while studying them: she found the so-called medullary bone in the remains. This is a special structure that is chemically different from other types of bone tissue that appears in females before oviposition. Thus, it was proved that the femur belonged to a female pregnant at the time of death.

With this discovery, it became clear that in dinosaurs, as in birds, a sharp increase in estrogen during pregnancy provoked the appearance of medullary bone.

Tyrannosaurus as a dish for dinner. The fierce interspecific fights of dinosaurs did not end with broken noses. If someone's meat was available and the Tyrannosaurus rex was hungry, it could be considered that "the meal is served." Even if it meant the crackling of a cousin's bones.

Dinosaurs needed a lot of meat to survive in the prehistoric world. Lots of meat. The fossilized feces of dinosaurs contain the remains of half-digested bones and flesh. This indicates a fast metabolism in the animal, and the dinosaur quickly became hungry again.

In scientific circles, there is an opinion that tyrannosaurs were cannibals. Separate finds of bones preserved the imprints of teeth, it turns out that the bones of the tyrannosaurus were gnawed by the tyrannosaurs themselves. Scientists are not sure whether they fed on already dead individuals or killed on purpose: most likely, both options are correct.

"To the tooth": the unique structure of the tooth of a tyrannosaurus rex. Dinosaur teeth are a great prop for a horror movie: a dinosaur grabs a victim, sinks its teeth into it, splatters blood, and it is clear to everyone that the victim no longer has a chance. Tyrannosaur teeth were sharp as daggers, but that's not the only reason why they were deadly weapons.

When examining the teeth of tyrannosaurs, scientists noticed cracks, and at first they mistook them for damage (of course, because dinosaurs greedily and frantically devoured food). However, it turned out that this was not damage, but a special structure of the tooth. By trapping the prey, these cracks allowed the animal to be firmly held, minimizing the possibility of escaping from the dinosaur's mouth. This tooth structure is unique. Maybe it is her merit that tyrannosaurs went down in history as one of the largest predators on the planet.

"Little tyrant": a relative of the tyrannosaurus rex. In 1988, paleontologist Robert Bakker announced that a new relative, Nanotyrannus (literally, "little tyrant"), had appeared in the tyrannosaur family. The scientist made such conclusions by studying the find, the skull of a dinosaur from the University of Cleveland. Compared to the head of tyrannosaurs, this exhibit was much smaller and much narrower. In addition, he had more teeth. But was this predator a miniature relative of the tyrannosaurus rex, or was it still its cub?

Few people believed that Tyrannosaurus could change so quickly and so much, and the debate over the degree of relationship between Nanotyrannus and Tyrannosaurus lasted quite a long time. And in 2001, the best-preserved young tyrannosaurus rex was discovered in Montana - it turned out to be the same Jane, which was described above. This teenage dinosaur had much in common with both the Cleveland University find and the large tyrannosaurs.

The dispute about Jane's species remains open - as well as the question of the very existence of the subspecies of tyrannosaurus Nanotyrannus.

Seeing off the mind: intelligence allowed tyrannosaurs to become a super-predator. There is another mystery in the evolution of the tyrannosaurus - and it is again associated with "miniature" dinosaurs.

More recently, in 2016, scientists named and described a new type species of Tyrannosaurus rex, Timurlengia euotica. He got this name in honor of Timurleng, the founder of the Timurid Empire in Central Asia: because the main finds that led to such discoveries were made on the territory of modern Uzbekistan. The second part of the name means "good ears" - this individual had long inner ear canals designed to pick up low-frequency sounds.

But the most interesting thing is the size. Scientists could not understand how a dinosaur measuring 3-4 meters in length, with a weight of about 170-270 kg, that is, in general, about the size of a horse, could survive in the ancient world. Moreover: how could he develop into a formidable super-predator weighing more than 7 tons? The answer lies in his intellect: yes, yes, it was the intellect that allowed the little predator to dominate the cruel world.

"Head off the shoulders": a tyrannosaurus could behead the enemy. Studying the bony collar of Triceratops, scientists have discovered new facts about the habits of tyrannosaurs. On the bone collars of Triceratops, teeth marks were found, which indicated that the tyrannosaurus not only grabbed and gnawed the collar of the Triceratops, but also literally pulled it off. The question is: why would a predator gnaw on that part of the animal where there is no meat?

It turns out that an adult tyrannosaurus bit off the head of a Triceratops. The neck of a Triceratops was considered a delicacy, and the bony collar served as a hindrance. Evidence of this is the traces of teeth on the neck joints of the Triceratops, which could only be there if the victim's head was torn off.

Terrible cooing of a tyrannosaurus rex: they did not make roaring sounds. To find out what sounds tyrannosaurs made, scientists examined their closest living relatives. Studying the sounds of the so-called archosaurs - crocodiles and birds - paleontologists came to the conclusion that dinosaurs did not make wild roaring sounds that frighten all living things.

If a Tyrannosaurus rex made something similar to what birds make, it must have had an air sac instead of vocal cords. Without vocal cords, a dinosaur would not be able to roar. The real voice of one of the most dangerous dinosaurs might disappoint you: most likely, it was like cooing.