How dinosaurs used to live. Dinosaurs: how did they become extinct? When did the dinosaurs go extinct?

Can you imagine what dinosaurs looked like when they ruled this earth many years ago? Let me answer this question. Some species of dinosaurs, once the largest creatures on the planet, were as tall as a four-story building and weighed more than the combined weight of a hundred cars.

Interested? There is still a lot known about dinosaurs interesting facts. As you may have guessed, it is these prehistoric reptiles that we will talk about today on the site about animals. We will tell you what groups dinosaurs are divided into, about their evolution, as well as hypotheses about why dinosaurs became extinct.

These giant creatures get their name from the Greek and Latin language. Speaking in simple words, dinosaur means "terrible lizard".

They are usually named after their body features, the location where they were found, or after the person involved in their discovery. The name usually consists of two Greek or Latin words or combinations thereof.

Types of dinosaurs. All dinosaurs were different from each other. Their food preferences were different, they were different sizes, the walking style of some was different from others, there were many more features.

Dinosaur groups

Sauropods- a group of herbivorous dinosaurs, which was distinguished by the most impressive size among the rest - a large body, a long tail and a neck, which, like the giraffe, helped to reach tree foliage for food.

Theropods- carnivorous dinosaurs. This group of predators had excellent eyesight, sharp teeth and equally sharp claws, which were very helpful in hunting.

- large herbivorous dinosaurs with huge bony plates located along the long spine. It is believed that these spines not only served as a deterrent to predators, visually increasing the size of the dinosaur, but also participated in thermoregulation processes due to the huge number of blood vessels located in them.

Brachiosaurs- huge dinosaurs that lived in herds. Their size can be compared to two double-decker buses stacked on top of each other. Like all sauropods, they had long neck, helping them get succulent foliage from tall trees.

Some dinosaurs preferred to move exclusively on two legs, which is why they were called bipeds, while others walked only on four. But there were species that could move freely on both two and four legs.

Evolution of dinosaurs

Dinosaurs appeared about 230 million years ago; their ancestors are reptiles that inhabited the watery expanses of the Earth. In the process of evolution, terrestrial species of dinosaurs arose. Their appearance very different from more primitive reptiles. Even now, no one can say for sure why such changes occurred. But one thing is clear - as a result of evolution, the strongest survive. And only a small percentage is due to chance.

The first dinosaurs were small in size (about 10-15 feet in length) and had a fragile physique. They moved quickly on two legs. Their remains were first discovered back in the last century in Madagascar, off the coast of southern Africa.

Eoraptor is one of the very first dinosaurs, which appeared about 228 million years ago. In size it is not more dog, but, nevertheless, it was a predator that moved quickly on two legs.

Not all prehistoric animals were dinosaurs. In addition to them, there were many other representatives of the fauna.

Dinosaurs inhabited exclusively land. None of them lived in the sea or flew. True, some carnivorous species eventually developed feathers and evolved into birds.

Not all dinosaurs were huge. Among them there were also small specimens. The smallest one was the size of a chicken, which is why it was called Compsognathus.

Birds are the only surviving descendants of dinosaurs. Humans themselves, as most experts suggest, never coexisted with dinosaurs.

The number of teeth in each type of dinosaur was completely different. Some did not have them at all, others had 50-60 thick teeth, shaped like a cone. But hadrosaurs had the most teeth - about 960. An interesting fact is that if an animal lost or broke a tooth, a new one always grew in its place.

Life expectancy varied significantly among different species of dinosaurs. Larger species could live up to 100 years, while larger species small dinosaurs it was significantly shorter.

Why did dinosaurs become extinct?

Extinction is the process of disappearing entire species of animals. This occurs when the death rate exceeds the birth rate and is considered a natural result of evolution. That is, if organisms cannot adapt to the conditions of existence in environment, they disappear.

Dinosaurs became extinct about 65 million years ago as a result of sudden climate changes following the collision of a large asteroid with the Earth. This is the most popular theory explaining the death of dinosaurs.

It is believed that a large asteroid crashed into the Earth at high speed. Its dimensions were about 10 km in diameter. Because of this, a wave of earthquakes occurred, raising clouds of dust, which caused the death of the dinosaurs.

According to another theory, a strong cooling occurred on Earth, and animals, without feathers or fur, could not survive in such climatic conditions.

Today it is believed that only birds have preserved some characteristic features, inherent in the distant past to dinosaurs.

Fossil animal bones have been found on every continent without exception. It is quite possible, it may even be somewhere near you.

Amazing and little known facts from the life of dinosaurs. Hunting strategy of ancient predators.

Many scientists ask this question. Was there a hunting strategy for northern dinosaurs?
There is an assumption that the dinosaurs of the north could “patrol” quite large areas, and when prey is detected, pursue its prey over long distances. What is this assumption based on? Scientists studied the thorax of predators and came to the conclusion that its structure allowed the lungs to absorb huge volumes of air.

Among modern scientists there is a theory according to which a period similar to a “nuclear” winter began on Earth after the fall of a 10-kilometer meteorite. Temperatures across the globe have dropped by an average of 7 degrees, according to the latest data. Some animals have remained unchanged to this day.

Did you know that the common shieldfish, which lives in ecologically clean regions of Russia, has the same appearance as its distant ancestors who lived on our planet 200 million years ago.

What were the very first dinosaurs?

The very first dinosaur was. Eoraptor lunensis is considered the most primitive representative of the first dinosaurs. IN rocks, whose age is 228 million years (these are the foothills of the Andes in Argentina), the skeleton of the first dinosaur was found.

It received its name in 1993. The animal was classified as a therapod. predatory dinosaurs order Ornithischians. The body length of this predator was 1 meter.

Nomination: Most ridiculous fossil animal.

The first place in such a non-existent nomination would have been taken by. Therizinosaurs had bird-like legs, a snout ending in a toothless beak, and each paw had four functional toes.

What were the largest dinosaurs?

208-65 million years ago, Sauropods lived on Earth. They were representatives of the suborder of saurian dinosaurs and lived in the Jurassic and Cretaceous periods.

These herbivorous animals had a long neck, a long tail and moved on four legs. were ubiquitous and inhabited most of the land.

Heavyweights.

The heaviest dinosaurs were the so-called. The heaviest among the heavyweights were probably the Titanosaur Antarctosaurus giganteus (giant Antarctic lizard), weighing 40-80 tons, the fossil remains of which were found in India and Argentina; Brachiosaurus altithorax (arm lizard), named for its long forelimbs (45-55 t);

Seismosaurus halli (earth-shaking lizard) and Supersaurus vivianae (both estimated to weigh close to 100 tons). The estimated weight of the Argentine titanosaur, Argentinosaurus, was approximately 100 tons. These data are published based on calculations made by scientists in 1994, which took the size of its giant vertebrae as a basis.

Brachiosaurus is the longest fossil animal.

The tallest and largest species of dinosaur whose skeleton was discovered to be almost complete was Brachiosaurus brancai. The remains of this animal were found in Tedaguru, Tanzania in Late Jurassic deposits. The age of the find is 150-144 million years. The remains of the animal were discovered and examined by German expeditions in 1909-1911. After studying the skeleton, it was exhibited in 1937 at the Natural History Museum of the Humboldt University in Berlin. This exhibit was assembled from the remains of several dinosaurs.

Its length was 22.2 meters, height at the withers was 6 m, and with its head raised - 14 m. Presumably the weight of the animal was 30-40 tons. However, based on this finding, scientists suggest that

No, this is not from the series . This is pure science...

For a whole century, Russian dinosaurs played hide and seek with scientists. Who won this exciting game?

“Russian dinosaurs, like the snakes of Ireland, are remarkable only because they are not there,” said American paleontologist Othniel Charles Marsh. 120 years ago he came to Russian Empire and was surprised to learn that not a single dinosaur bone had been found in our country.

It was incredible. Is it really in the big country there were no Mesozoic giants in the world?

Russian scientists have had no luck with dinosaurs. These animals reigned on the planet in the Jurassic and Cretaceous periods, when half of the current territory of Russia was covered by shallow seas. Herds of lizards roamed inland. But their bones were not preserved - they ended up in the area of ​​sedimentation, from where sand and clay were dragged into the seas to the burial sites. The bones arrived there ground into dust.

Occasionally, conditions on land developed that were suitable for preserving remains: the dinosaur drowned in a swamp or lake, or suffocated in the layers volcanic ash. But such burials were thoroughly destroyed over the past millions of years - glaciers passed through Russia, cutting away bedrock, and then melted glacial waters began to erode and break the fossilized bones.

Compared to the dinosaur cemeteries of Asia and America, where thousands of bones were dug up, this looked downright meager: in Russia, only one single bone turned out to be dinosaur.

But that's not even main reason failures that scientists had to endure. Everything that miraculously survived is today covered with forests, fields and inaccessible for study. Unlike the USA, Canada and China, Russia is unlucky: we do not have badlands - huge desert areas cut by gorges and canyons. All preserved bones of Russian dinosaurs lie deep underground and are very difficult to obtain. Occasionally, fossil remains are found in quarries, mines, and along the banks of rivers and streams. It will be a great success if they are noticed in time and handed over to scientists. But good luck for a long time was not enough.

At the end of the 19th century, fragments of bones that could pass for dinosaurs were occasionally brought to Russian museums. Strange ribs were found in the gravel used to pave the Kursk road. A piece of bone was delivered from Volyn-Podolia. An unusual vertebra was unearthed in the Southern Urals. What was accidentally obtained was described as the remains of dinosaurs, but later it turned out that these were the bones of crocodiles, marine reptiles, and even amphibians.

However, even such finds were few - all of them would have fit in a small basket. Compared to the dinosaur cemeteries of Asia and America, where thousands of bones were dug up, this looked downright meager: in Russia, only one single bone turned out to be dinosaur.

A small fragment of a lizard’s foot was dug up in the Chita region near a coal mine. Paleontologist Anatoly Ryabinin described it in 1915 under the name Allosaurus sibiricus, although from one bone it was impossible to determine which dinosaur it belonged to. It is clear that it is predatory - and that’s all.

Soon more valuable remains were found. True, two funny things happened with them at once.

One day, an Amur Cossack lieutenant colonel noticed that fishermen were tying strange weights on their nets - long stones with a hole in the middle. The fishermen said that they collect them on the banks of the Amur River, where a high cliff is eroded. According to them, it turned out that the entire beach there was covered with stone knuckles.

This was reported to the Academy of Sciences. An expedition was organized, which, right before the revolution, delivered more than a ton of fossilized remains to St. Petersburg. They assembled a large skeleton from them, describing it as new look duck-billed dinosaur. The lizard was given the name “Amur Manchurosaurus” (Mandschurosaurus amurensis).

True, evil tongues called him a gypsosaur, because he was missing many bones - they were molded from plaster. The skull - the most important part of the skeleton - was also plaster, only a piece of the braincase was real. Later it became clear that the original bones belonged to different types and genera of lizards. Now almost none of the paleontologists recognize Manchurosaurs. The irony also lies in the fact that the bones were collected on the right, Chinese bank of the Amur. So “gypsosaurus” should not be considered Russian, but rather Chinese.

The curiosity came out with a second skeleton. The lizard was dug up in the coal mines of Sakhalin by Japanese paleontologists and named the Sakhalin Nipponosaurus (Nipponosaurus sachalinensis). This was in the 1930s, when, after Russia’s defeat in Russian-Japanese war, Japan owned the island. Fifteen years later, Sakhalin again became Russian, but the dinosaur remained “Japanese”. And no more dinosaur remains were found here.

The search for dinosaurs in Russia and the Soviet Union remained unsuccessful for a long time. It was getting ridiculous. In the late 1920s, to the southern outskirts Soviet Union, a paleontological expedition headed to the Kazakh steppes. “The whole day the horse walked over countless dinosaur bones,” recalled its participant, paleontologist and science fiction writer Ivan Efremov. The bones covered vast areas of tens of kilometers. But not a single skeleton or skull was found - only fragments of bones. “They didn’t know how to study them back then, no one collected them,” says paleontologist Alexander Averyanov. Only half a century later, experts learned to identify extinct animals from fragmentary remains. But then the huge dinosaur cemetery in Kazakhstan had already been lost.

Then, for several years, Soviet paleontologists worked in the Kazakh Kara-Tau mountains, where layers of gray shale lie. These mountains contain a great variety of prints of fish, plants and insects from the Jurassic period. Unique skeletons of ancient salamanders, turtles, complete prints of pterosaurs, and a bird feather were discovered here.

The remains of almost all the inhabitants of the Jurassic lake and those who inhabited its shores were found. And again - no dinosaurs, although the Jurassic period was their heyday...

In the first half of the last century, numerous burial sites of Permian lizards, Devonian fish, and Triassic amphibians were discovered in Russia. Paleontological laboratories had everything from fossil insects to mammoth carcasses. Everything except the notorious lizards - that’s what Ivan Efremov called dinosaurs in the Russian manner.

Only in 1953 did paleontologists get truly lucky. On the high bank Kemerovo River Kiya near the village of Shestakovo, geologists came across the skull and incomplete skeleton of a small, dog-sized psittacosaurus, which was named Siberian (Psittacosaurus sibiricus). The skeleton was delivered to Moscow.

A paleontological expedition was immediately sent to Kuzbass, but luck turned against the scientists again. They did not find any remains - the water was high that summer, the layer with bones was flooded.

Three years later, at the request of Efremov, an expedition of Kemerovo schoolchildren, led by Gennady Prashkevich, went to Shestakovo, in the future famous writer, poet, translator. The guys then collected a whole box of bones, but, as it turned out in Moscow, they all belonged to mammoths and bison. Only half a century later, several more dinosaur bones were found in Shestakovo, including huge, bucket-like sauropod vertebrae.

Everything was no less complicated with the locations of dinosaurs on Far East. In the 1950s, an expedition from the Paleontological Institute tried to find dinosaurs in Blagoveshchensk. Excavations brought nothing but a handful of scattered bones. It was decided that the bones were redeposited here: once whole skeletons were broken by water, after which the fragments were carried away to another place. They put an end to the location. As it turned out later, it was in vain.

The lizards found in the Far East turned out to be very interesting - these are one of the last dinosaurs to live on the planet.

At the end of the 1990s, a road was being laid in the hills near Kundur, and in one of the construction trenches the son of geologist Yuri Bolotsky saw small vertebrae lying like a chain, one next to the other. It turned out to be the tail of a hadrosaur. Gradually excavating the remains, geologists uncovered a complete skeleton. The lizard was named Olorotitan arharensis. The first discovery was followed by others. Nowadays, excavations are carried out annually in the Far East, mainly in Blagoveshchensk. The local lizards turned out to be very interesting - these are one of the last dinosaurs that lived on the planet. They lived literally at the end of the great extinction.

The study of Russian dinosaurs in general has advanced greatly in the last twenty years. A dozen large locations were found, and valuable remains were found in earlier famous places finds.

The main burial places of Russian dinosaurs are located beyond the Urals - in Kundur, Blagoveshchensk, Shestakov.

A unique location was discovered on the banks of the Kakanaut River on the Koryak Highlands - this is the northernmost point of discovery of dinosaurs on the planet. Bones from seven families and egg shells from at least two species of dinosaurs have been found here. Remains of Cretaceous lizards were also found in Buryatia (locations Murtoy and Krasny Yar) and Krasnoyarsk Territory (Bolshoy Kemchug). Dinosaurs of the Jurassic period were found in Yakutia (Teete) and in the Republic of Tyva (Kalbak-Kyry).

A small burial site of Jurassic reptiles was discovered near the town of Sharypovo in the Krasnoyarsk Territory. Local historian Sergei Krasnolutsky came up with the idea: once in the neighboring Kemerovo region found dinosaurs, then they can be found here in the Krasnoyarsk Territory.

In search of bones, he went to a coal mine. For a long time nothing came across, but finally the local historian saw the broken shells of turtles. There were so many of them that this layer was later called turtle soup. And nearby were bone plaques and teeth of crocodiles, long curved claws of dinosaurs that lived in the mid-Jurassic period.

This time is practically a “blank spot” in the evolution of terrestrial life. Very few traces of him remain. It is not surprising that excavations in Sharypovo, which have been ongoing for several years, have led to the discovery of new animals. Among them are an as yet undescribed stegosaurus and the predatory dinosaur Kileskus (Kileskus aristotocus), a distant ancestor of the famous tyrannosaurs.

In the western part of Russia there are no burials with intact skeletons and skulls of dinosaurs. Here, primarily in the Volga region and Belgorod region, mostly scattered remains are found - individual vertebrae, teeth or bone fragments.

An interesting discovery was made a hundred kilometers from Moscow, near the Peski railway station, in a quarry where white limestone is mined. In these quarries there are karst sinkholes from the Jurassic period. In the early 1990s, bulldozers opened up a whole chain of ancient caves. 175 million years ago they flowed underground river, originating in the lake. The river carried the remains of animals, tree branches, and plant spores underground.

Over the course of several years, paleontologists managed to collect numerous turtle shells, bones of amphibians, crocodiles and ancient mammals, fish skeletons, and spines. freshwater sharks and remains of predatory coelurosaurs (Coelurosauria). These dinosaurs were probably about three meters long, although the bones found were small: teeth the size of a fingernail and a claw smaller than a matchstick.

Gradually, the picture of the life of Russian lizards is becoming more and more complete. Surely new burials will be discovered. And those that have been known for a long time constantly bring surprises in the form of bones of previously unknown dinosaurs.

Othniel Charles Marsh, who insisted that there were no Russian dinosaurs, concluded his statement by saying that sooner or later the remains of these animals would be found in Russia. The American paleontologist turned out to be right, although he had to wait a long time.

Now let's remember the extinct animals that lived in Russia:

This dinosaur was one of the largest representatives of its family, reaching a length of 12 meters. It is characterized by features unique to hadrosaurids, the most obvious of which is the uniquely shaped crest crowning the skull. Like other hadrosaurs, Orolotitan could move on either two or four legs. The structure of the skull made it possible to grind tough plant foods, and numerous teeth were replaced throughout life. A wide, hollow ridge formed from the expanded bones of the skull was pierced by the nasal passages and was probably used to produce trumpet sounds. It is also noteworthy that these are one of the last dinosaurs to live on the planet. They lived literally at the end of the great extinction.

These primitive herbivorous therapsids existed even before dinosaurs - about 267 million years ago. At that time, the earth consisted of one single supercontinent, Pangea. But it is noteworthy that until now the remains of Estemmenosuchus have been found only in Perm region. These were quite large animals, the size of a modern minibus. They led semi-aquatic image life (like hippos). The basis of their diet could be dead trunks of calamites. However, the structure of the dental system does not exclude omnivory (for example, feeding on carrion).

A representative of the infraorder of horned dinosaurs that lived in the Early Cretaceous period approximately 130-100 million years ago. All species of psittacosaurs (and at least 10 of them are identified from fossil evidence) were bipedal herbivores the size of a gazelle, with a characteristic high, powerful beak on the upper jaw. At least one species of psitaccosaurus had long, bird-like feather-like structures on its tail and back, likely serving a display function.

Elasmotherium is a genus of rhinoceros that lived in Eurasia from the Pliocene to the Pleistocene. They were distinguished by their large sizes (length up to 6 meters, height up to 2.5 meters, weight up to 5 tons). Their main feature is a large dome-shaped growth on the forehead. Some scientists suggest that it had a long (more than 1.5 m) and thick horn. At the same time, the bones of the dome are very thin, and the dome itself has a spongy structure. In general, Elasmotherium lived not only on the territory of Russia. They were distributed from Western Europe to Eastern Siberia. Closely related but more primitive genera are known from the Miocene-Pliocene of China, Iran and Spain.

One of largest predators Permian period. The length of its skull is about 60 cm, and the length of its entire body is up to 6 meters. Titanophoneus were distinguished by powerful incisors and canines, and 8-9 pairs of small postcanine teeth. The legs are powerful, not very long, with wide hands and feet (possibly there was a swimming membrane). The tail is long. Overall the skeleton is quite light. Initially, the Titanophone was considered aquatic predator, like a crocodile, but adults probably hunted large vertebrates on land.

A prehistoric synapsid belonging to the clade Anomodontia, living about 260 million years ago in the late Permian period. Suminia's teeth were quite large in relation to the size of the body, with one cusp on each tooth and many serrations, like those on a knife. Throughout life, teeth fell out and grew back. The eye socket was quite large. The paws were prehensile, leading the researchers to suggest that Suminia was the earliest tree-climbing vertebrate.

7. Titanosaurus (Ulyanovsk region).

A group of lizard-hipped dinosaurs of the sauropod infraorder that lived in the Jurassic and Cretaceous periods about 171-65.5 million years ago on all continents of the planet except Antarctica. They were herbivorous dinosaurs that had long necks and tails, and walked on four legs. They reached a length of up to 35-40 meters and weighed between 88 and 110 tons.

The Age of Dinosaurs, or Eras and Periods of the Earth

Scientists have identified several stages in the history of the Earth. They are called "era". Eras are divided into periods, each of which lasted several tens of millions of years. In different books The beginning and end years of eras and periods may vary slightly: There are different opinions in science. The Paleozoic era, or Paleozoic, began 570 million years ago. Over the 340 million years that it lasted, the living world changed amazingly. The waters and land were populated. Vertebrates arose (although the time of mammals and birds had not yet come). The living world has become incredibly diverse. But the molecules that made up the organisms of that time remained approximately the same. These molecules have changed little to this day. So the molecules that make up the human body are very similar to the molecules, for example, of an ancient crustacean. The Paleozoic era is divided into 6 periods: Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian. At the beginning of the Paleozoic, an amazing “explosion” of life occurred: many species of invertebrates were formed. But at first this happened only in water, especially in warm seas. The land remained deserted. Mastering sushi. Somewhat earlier than 400 million years ago, plants began to populate the land. At first they were inconspicuous sprouts. But after millions of years, the Earth was overgrown with dense forests. Following plants, invertebrate animals mastered life on land. The abundance of food on land attracted lobe-finned fish. Only they could, relying on their unusual limbs, move outside the water. And primitive lungs allowed these fish to breathe air. Many millions of years passed, and lobe-fins, gradually changing, turned into new biological species. But these were already animals of a new class - the class of amphibians (amphibians). Carboniferous period Paleozoic era(or carbon for short). Began 345 and ended 280 million years ago. In the humid heat, forests grew quickly and abundantly. After millions of years, these trees turned into coal. Amphibians reigned in the swamps and surrounding forests. And tiny ones. And huge five-meter tailed predatory stegocephals. At the end of the Carboniferous, the first reptiles appeared. The Permian period, or Permian (280-230 million years ago) was marked by the rapid emergence of new species of reptiles. The Mesozoic Era, or Mesozoic, began 230 million years ago and lasted 165 million years. During this time, higher (flowering) plants arose. Giant lizards (dinosaurs, ichthyosaurs and others) appeared, reigned on the planet and mysteriously died. Mammals and birds evolved. The Triassic period of the Mesozoic, or Triassic (230-190 million years ago) was marked by the dominance of reptiles on land, in water and in the air. The most famous of these reptiles are dinosaurs. Dinosaurs walked either on four legs or on two. It is very likely that some dinosaur species were warm-blooded. Judging by the tracks of dinosaurs and the remains of the eggs they laid, these animals were caring parents. Dinosaurs laid eggs in piles of plant debris. As these remains decomposed, they released heat, and the clutch of eggs was heated. And the mother, remaining nearby, guarded the nest (the relatives of dinosaurs, crocodiles, also do this). Recently, paleontologists discovered traces of the tragedy: a small skeleton of a female dinosaur lying on a fossilized clutch of eggs. Probably the mother warmed the eggs and died, but did not leave them. It is possible that eggs of some other species also incubated dinosaurs. It is unknown what color the skin of dinosaurs was. Perhaps, like many lizards today, snakes are bright and colorful. This is how artists draw dinosaurs. The name comes from Greek words meaning "horrible" And "lizard". In fact, not all dinosaurs are “terrible.” Dinosaurs Triassic period They were, as a rule, small, graceful, fast animals. They ran on their hind legs, and their long tail helped them maintain balance. And in the next almost one and a half hundred million years, when dinosaurs dominated the land, they were mostly small. Some are as tall as a man, some are a little bigger, and some are even as tall as a chicken. The Jurassic period of the Mesozoic, or Jurassic (190-135 million years ago) is the era of the appearance of gigantic dinosaurs. Supergiants. During the Jurassic period, the largest animals on land appeared -. A heavy body on thick legs, with massive blunt claws on the toes. The neck is long. The tail is even longer. Without moving from their place, moving only their necks, they plucked and ate whole mountains of greenery.

The brain of sauropods is too small in relation to the body - about the size of a fist, or even less. Despite this, the behavior of these lizards was most likely complex. They lived in herds (judging by the fossilized traces). Perhaps together they defended themselves from predators that appeared in the Jurassic. But how did they fight back? This is unknown.

Powerful predator of the Jurassic period. A fast animal weighing about a ton, armed with huge claws and teeth that look like curved daggers. Allosaurs attacked large herbivorous dinosaurs in packs. Carnivorous dinosaurs could not chew food with their cutting teeth. They swallowed pieces of meat whole. With their teeth, predators ripped open the tough skin of their prey and crushed bones.

The largest of these dinosaurs reached 9 m in length. Such a mountain consumed tons of green food. Sharp long bone spikes stood out on the tail to fight off predators. The bone plates on the back are apparently shields, salvation from enemy teeth and claws. The Cretaceous period of the Mesozoic, or Cretaceous (135-65 million years ago) is the era when dinosaurs and other reptiles continued to rule the Earth. And at the same time everything became more mammals(they appeared in the Triassic) and birds (they appeared in the Jurassic). Mammals lived side by side with dinosaurs for many millions of years, hiding and running away from these ferocious predators. It was no easier for the birds: although dinosaurs could not fly, they even reached bird nests in trees. Reptiles in the sky. Pterosaurs (the name of the order of winged reptiles) took to the air at the end of the Triassic period and flew until the end of the Cretaceous. Each of their wings consisted of a leather membrane that was stretched between the body, limbs and one of the surprisingly long fingers of the forelimb. The remaining fingers were ordinary, and the reptiles clung to branches and stones with them, resting.

Animals with thin, hollow (like bird) bones. The first pterosaurs had a tail and teeth. After millions of years, pterosaurs got rid of this “heaviness”. Pterosaurs were obviously warm-blooded. Their body was covered with hairs - “wool”. The brain of these reptiles was well developed. Small pterosaurs (from 8 cm in wingspan) caught insects. Large ones (wingspan 1 meter, 2 and 6 meters) snatched fish, cephalopods and other food from the water. Surely pterosaurs nursed their young. Pterosaurs are not dinosaurs! Reptiles that are not extinct. During Mesozoic era snakes, turtles, lizards, and crocodiles appeared. They were not very different from the current ones. Reptiles in the sea. The most adapted to life in water were ichthyosaurs. They appeared back in the Triassic. Outwardly, they are strikingly similar to dolphins. The reason is the same lifestyle. Only the tail fin of ichthyosaurs is not horizontal, like that of dolphins, but vertical.

In water, reptiles have no place to lay eggs, so ichthyosaurs immediately gave birth to “ready” babies. A variety of long-necked plesiosaurs, crocodile-like giant mososaurs, and other aquatic lizards hunted fish and cephalopods. And sometimes they fought fiercely with each other. All fossil aquatic reptiles are not dinosaurs! Predatory lizards were distinguished by a relatively large and developed brain, and their behavior was complex. Apparently, some even knew how to hunt together, “coordinating” their actions. Catastrophe. Until the end of the Cretaceous period, reptiles dominated both land and sea. It was at the end of the Cretaceous that the largest land predator of all eras appeared -. About 65 million years ago, dinosaurs and pterosaurs disappeared almost simultaneously, all sea ​​lizards. They all died out without leaving descendants. Cephalopods - ammonites and belemnites - died. What happened? What is the cause of this environmental disaster? There are many assumptions, and all of them are controversial. Here is one of them: a colossal meteorite, even an asteroid, crashed into the Earth. The monstrous explosion created such a cloud of dust that sunlight faded for a long time. Living conditions deteriorated so much that the dinosaurs could not bear it. Everything is very likely. But why did the closest relatives of dinosaurs - crocodiles - survive this ecological disaster? The causes of the great extinction at the end of the Cretaceous period are still a mystery to science. Birds appeared on Earth in Jurassic period. The first fossil bird found was named.

The ancestors of birds are very close to the ancestors of dinosaurs and crocodiles. External resemblance birds and dinosaurs - no doubt. There are many similarities in other properties of the body of these animals (for example, scales on the legs of birds). However, one cannot assume that birds are descendants of dinosaurs. They are their close relatives. Archeopteryx was covered in feathers. Undoubtedly, he was warm-blooded. He could fly, but not for long. However, the skeleton of the tail of Archeopteryx is almost like that of a lizard (later this part of the spine disappeared in birds). The mouth is toothy. There is no beak yet. But there were three fingers left on each wing - to cling to tree branches. It is still unclear how the small (magpie-sized) Archeopteryx used its wings. Did he flutter from branch to branch? Or he ran on the ground and, jumping and flapping his wings, grabbed flying insects with his teeth and escaped from predators. Archeopteryx still has many signs of reptiles. Gradually, such signs became less and less. Already in the Cretaceous period there were many various birds shouted (they didn’t know how to sing yet) in the treetops. In swift, agile flight, the birds snatched prey from under the beaks of less agile pterosaurs. Mammals. The first mammals appeared at the end of the Triassic period - later than dinosaurs, earlier than birds. The ancestors of mammals were animal-like reptiles. They differed in many ways from other reptiles - the ancestors of dinosaurs. The beasts were most likely warm-blooded animals (at least many of them). Probably, instead of scales, their skin was covered with hair. There were other features of the body. So, there were many different glands on the skin that secreted sweat and other fluids. Perhaps in some species of these animal-like reptiles the glands secreted a liquid similar to milk. Such liquid could be licked and thus fed by the hatchlings from the eggs (as baby platypus do today). Then the cubs began to be born and develop as it happens today in marsupials. Finally, a special organ arose for feeding the baby inside the mother’s body - the placenta. The first mammals were small animals (like a shrew, like a hedgehog). For many millions of years they existed secretly in dangerous world dinosaurs. Apparently they were hiding in the thickets. They hunted only at night, for insects, shellfish, and other edible things. Perhaps they ate reptile eggs. , or Cenozoic. It began approximately 65 million years ago and continues to this day. During this time, mammals conquered land, water and air. Adapting to new living conditions, mammals have changed. Evolution continued.

Hi all! Today we will talk about animals that reigned on Earth in the past. Now we will look at who are dinosaurs? Let's look at predators and herbivores, and also find out what parents dinosaurs were and some theories of their extinction.

After reigning on Earth for 160 million years, dinosaurs disappeared from the face of the planet about 65 million years ago. Where did these giant reptiles come from? What did they really look like and why did they go extinct?

Dinosaur translated from Greek means a terrible or terrible lizard. About dinosaurs scientific knowledge are formed mainly from the study of fossils, which have been turned into stone by the fossil remains of animals or plants.

Modern paleontologists have a fairly clear idea of ​​how dinosaurs originated, what their lifestyle was, anatomy, habitat, species diversity, distribution and reproduction in prehistoric form.

Experts can judge from minor flaws in fossilized bones about the muscular system of dinosaurs, but they judge from the appearance of individual bones what illnesses these ancient lizards suffered from.

If you carefully study the skull of a dinosaur that died 200 million years ago, this will give an idea of ​​the dinosaur's nutritional structure and the size of its brain.

Fossil eggs reveal the story of baby dinosaurs. But such hypotheses as, for example, whether ancient reptiles had hair and what color their skin was, confirmation is much more difficult to find.

Age of dinosaurs.

From its origin, approximately 4500 million years ago, the entire history of the Earth is divided into eras (you can learn more about the geological history of the Earth). Most of the Mesozoic or Middle era is covered by the era of dinosaurs.

The Mesozoic era, in turn, consists of three periods - Triassic (225 - 185 million years ago), Jurassic (185 - 140 million years ago) and Cretaceous (140 - 70 million years ago).

Even before dinosaurs appeared, reptiles existed on Earth. Many new species arose at the beginning of the Triassic period. These are, for example, the fleet-footed kinodonts (“dog-toothed”), which hunted clumsy herds of herbivores.

Like most modern lizards, the paws ancient reptiles were located on the sides of the body. They were replaced by archosaurs (“dominant lizards”).

One group of these reptiles differed from all others in their body structure - their limbs were located vertically under the body.

That successful skeletal structure that we find in their descendant dinosaurs probably originates from here.

The first real dinosaurs walked the Earth towards the end of the Triassic period. However, the heyday of their era occurred in the Cretaceous period, when the number and diversity of species of these reptiles reached their apogee.

Scientists today count over 1000 species of dinosaurs, which are clearly divided into two groups - carnivorous and herbivorous dinosaurs.

Sauropods.

Dinosaurs ranged in size from giant sauropods to small predatory Compsognathus, which were no larger than a rooster.

These were herbivorous giants with a huge body, a small head and a long neck, like a giraffe, which allowed them to reach the tops of trees to feast on the most delicious leaves.

They tore leaves from trees with teeth that looked like nails, and chewed them into a homogeneous mass with blunt molars. Diplodocus (“double lizard”) reached a length of 26 meters and weighed 11 tons.

The brachiosaurus was 28 meters long, 13 meters high and weighed 100 tons - the same as 16 African elephants. They ate only plants and to survive they had to eat about a ton of leaves a day.

In the skeletons of some fossil sauropods, huge stones were found in the place where the stomach should have been. These ingested stones apparently helped to crush leaves and rough twigs during the digestion process.

Self-defense.

Many herbivorous dinosaurs moved in groups in search of food. To more successfully fight off predators, they often gathered in large herds.

Triceratops did this to protect its young. Adults, in the event of an attack, surrounded the young in much the same way as elephants do now.

However, many “peaceful” dinosaurs were also decently armed. Like a rhinoceros, the Triceratops rushed into battle and pierced its enemy with two huge sharp horns, which were located in the frontal part of the snout.

Pinacosaurs stunned their opponents with blows from a heavy bone growth at the tip of their tail. Other herbivorous dinosaurs, like Stegosaurus, were protected by rows of large bony plates along their backs and sharp tail spines.

Tyrannosaurus

Predatory dinosaurs were allowed to tear their prey to pieces sharp teeth curved inwards, and was held in place by sharp and long claws.

The largest of the carnivorous dinosaurs was the Tyrannosaurus ("titan lizard"), it weighed 8 tons and was 12 meters tall.

Its curved teeth reached 16 cm in length - almost as long as a human palm (depending on which one, of course).

Dinosaurs, despite their size, could move very quickly. Long-legged “ostrich” dinosaurs could run at speeds of up to 50 km/h.

Of course, such heavyweight dinosaurs, such as the 35-ton Apatosaurus, probably moved at the speed of a modern elephant, and the 100-ton clumsy Brachiosaurus could hardly move at a speed of more than 4 km/h (like human walking).

Sauropods needed strong legs to move. A springy heel-to-toe step, like a human one, required a very large expenditure of energy, and a large dinosaur would not have gone far with such a step.

Sauropods (i.e., giant "lizard-footed") ran rather than walked. To support the massive torso, their limbs had to step on the entire plane of the sole.

And therefore, between the “heel” and the toes they had a thick keratinized cushion, just like a modern elephant’s sole.

Caring parents.

It was long believed that dinosaurs built nests and laid eggs. But how the young animals were raised remained a mystery; and only in 1978 this curtain was lifted when a nest with newborn babies and eggshell V American state Montana.

The length of the eggs did not exceed 20 cm, and some hatchlings were up to 1 meter long. These dinosaurs were very large for newborns, which means they remained in the nests for a long time after birth.

Scientists, based on these data, came to the following conclusion: parents cared for their babies until they were old enough and could take care of themselves.

Many of the cubs found in Montana had worn teeth. This means that their parents fed them in the nest, as birds do now.

Some experts had doubts that the giant parents were capable of feeding their offspring without causing harm.

But after all, largest reptile our days, the alligator also nurses its offspring and does it with the greatest care.

There is growing evidence that some large species of dinosaurs, like mammals, were viviparous.

Since many dinosaurs were constantly moving to escape from enemies and in search of food, they did not have time to lay eggs and then wait weeks or even months for small dinosaurs to appear and grow up.

And besides, the largest dinosaur egg that has been found does not exceed 30 cm in length. The baby that hatched from it was not much larger, and it would have to grow very quickly in order to reach the size of an adult dinosaur.

And therefore, some scientists have put forward a theory according to which largest dinosaurs were born alive - and quite large.

The first fossils.

For hundreds of years, people have encountered fossilized dinosaur bones, but few of them could have guessed what they were. Some even considered them to be the bones of giant men!

It was only in the 1920s that people began to realize that they were looking at the remains of extinct giant reptiles.

In 1822, Gideon Mantell found some huge teeth in a quarry in Sussex County, in southern England.

He, after noting the similarity of these teeth with the teeth of the South American lizard iguana, guessed that the found teeth belonged to a reptile, and came up with the name iguanodon, i.e. “iguan-toothed” for it.

Dinosaur fossils are found in almost every corner of the world. They are found on all continents, including Antarctica.

Teeth and bones are found most often because these skeletal elements are much less susceptible to decomposition than soft tissues (viscera, skin).

Footprints take second place. They are in many cases found on paths that dinosaurs made in soft ground.

Who hunted whom, as well as the places of settlement of the lizards, can be determined by their tracks. Fossilized footprints are called residual fossils because they do not actually belong to the animal itself.

Coprolites (fossilized dinosaur excrement) are dissected and examined, along with intestinal contents and stomach stones, to find out what the ancient dinosaurs ate.

Imprints of dinosaur skin have also been found. They can tell a lot about the plastic armor of their owners.

No one knows what color dinosaurs were. Their skin, without having time to petrify, decomposes too quickly.

Predatory lizards, according to some scientists, had a protective coloration, which allowed them to blend into the terrain and sneak up on prey unnoticed.

Other reptiles, herbivores for example, were very large and were not afraid of predators, and they may have had bright colors in order to attract the opposite sex.

Sudden death.

Dinosaurs went extinct about 65 million years ago, at the end of the Cretaceous period. There are several theories on this matter, but paleontologists still cannot give a convincing explanation for the reason for their death.

According to one theory, A star exploded near Earth, covering the planet with deadly radiation.

At one time, scientists put forward such a theory that, being cold-blooded animals that are not able to regulate their own body temperature, they simply died out from the cold snap that swept the entire planet at the end of the Cretaceous period.

But now, when evidence has appeared that some species of lizards were warm-blooded, this theory no longer explains the mystery of their death.

In Mexico, on the Yucatan Peninsula, traces of a giant crater were discovered. This suggests that a huge meteorite collided with the Earth, and this collision was accompanied by a powerful explosion.

Huge clouds of dust rose into the atmosphere (more about the atmosphere), which hid the sun for several months, and this led to the destruction of almost all life on Earth.

Winters have become colder or summer heat strengthened, we benefited from it small mammals that are capable of hibernating. This is another theory of the extinction of dinosaurs; by the way, it is the most popular and widespread.

But the real reason We will apparently never know the death of the dinosaurs.

Well, that's all about these terrible lizards. I hope that this article helped you find out who dinosaurs were and who they really were. But there is still a lot of unknown in this area, and I think that scientists will gradually find answers to these riddles...