How did dinosaurs originate? History of Dinosaurs

Life on our planet began about 4.5 billion years ago, but for more than 4 billion years it existed in the form of very primitive, tiny single-celled creatures that could not yet be divided into animals and plants.

Gradually, organisms became more complex and diverse. In the Cambrian period, about 550 million years ago, algae, sponges, mollusks, worms, coelenterates and many other new forms of life appeared. This time was called the "Cambrian explosion". Millions of years passed. The first vertebrates arose in the ancient seas - fish-like fish and lobe-finned fish.

The turning point in the evolution of life on Earth was the emergence of animals from water to land. This process took a long time - about 100 million years. At first, lobe-finned fish came onto land only for a short time. True terrestrial vertebrates - armored-headed amphibians, or stegocephals - appeared in the Devonian after their ancestors learned to get food on land. In the Carboniferous period, stegocephalians began to be replaced by the first reptiles that appeared - cotylosaurs, which became the ancestors of all other groups of reptiles. In the middle of the Permian period, cotilosaurs became extinct, giving way to more developed animal-like vertebrates - therapsids, among which were both herbivorous and predatory species. Animal-like animals remained the most common reptiles in the Early Triassic. At the end of the Permian period, thecodonts, or archosaurs, the most ancient lizards, appeared. The evolution of reptiles proceeded very quickly and violently. The Mesozoic era became the real kingdom of reptiles. It began about 235 million years ago and lasted approximately 160 million years. The Mesozoic is divided into three periods: Triassic, Jurassic and Cretaceous. The first two periods were much shorter than the third, which spans about 70 million years. At that time, there were no competitors for reptiles from other animals, so under the influence of the diversity of living conditions, a variety of types of reptiles appeared. They have adapted to the most different conditions terrestrial environment. Subsequently, many of them secondarily adapted to life in water (ichthyosaurs, plesiosaurs). Some became aerial animals (pterosaurs). At the end Triassic period The first land turtles and crocodiles appeared, which survived all natural disasters and survived to this day. Dinosaurs also appeared in the Triassic period. The oldest known dinosaurs were Eoraptor and Herrerasaurus.

Main groups of dinosaurs

Dinosaurs descended from thecodonts, namely from slender, fleet-footed ornithosuchians, which are considered the direct ancestors of dinosaurs. Among dinosaurs, two groups are distinguished: ornithischians and lizards. The pelvis of the first group is similar to the pelvis of birds, and the second is similar to the pelvis modern reptiles. Ornithischians also had an additional bone at the end of the lower jaw that covered the jaws in the form of a horny beak. There was another group of dinosaurs - segnosaurs. Their structure had features of both ornithischians and saurians, and some features are generally characteristic only of segnosaurs

In the Jurassic period, lizards flourished. The first of them were predators, they ran on strong hind legs and grabbed prey with their front legs. Later, herbivorous species evolved from carnivorous dinosaurs. They needed a huge amount of food, their body weight was constantly increasing. They used all four limbs while walking. Based on the structure of their legs, they were called lizard-footed dinosaurs, or sauropods. This group includes 40 genera. The bipedal predators were called beast-footed dinosaurs, or theropods. There are 150 genera.

Lizard-hipped dinosaurs Theropods

These dinosaurs walked on their hind legs with three toes armed with sharp claws. Some of them were ferocious hunters, others were scavengers. All theropods had backward-curved teeth. They did not know how to chew food and swallowed whole pieces of prey. They were the most different forms and sizes - from a sixty-centimeter saltop to a fourteen-meter tyrannosaurus.

At the end of the Triassic period, small and very graceful coelurosaurs existed. They had light, hollow bones. They ran very fast on long hind legs, the front legs were half as long. To hunt, coelurosaurs gathered in packs, so they could attack large animals. This group includes the three-meter-long Coelophysis (“hollow form”) and the five-meter-long Halypicosaurus (“agile lizard”). Even more graceful species of coelurosaurs lived during the Jurassic period. These are a two-meter ornitholestes (“bird predator”) and compsognathus (“graceful jaw”), only 60 cm long and weighing 3kg. According to one hypothesis, Archiopteryx evolved from coelurosaurs. The descendants of Coelophysis also became powerful predators (Allosaurus, raptors, tyrannosaurus).

In the sediments of the end Jurassic period 60 skeletons of Allosaurus ("another reptile") were found. The largest of them reached 12 m in length and weighed 1-2 tons. Allosaurus had three toes with curved claws on its front paws. Its teeth had sharp, serrated back edges that cut through hide and bone like a saw.

Its close relatives, even more gigantic (up to 13m in length and weighing up to 7t), lived in the Late Cretaceous period. These are Giganotosaurus ("giant southern lizard") and Carcharodontosaurus ("huge shark-toothed lizard"). The skull of the carcharodontosaurus reached one and a half meters in length, and its mouth was so large that it could swallow an adult person whole. One of the most dangerous predators of the Late Cretaceous there was a tyrannosaurus (“tyrant lizard”). Its height reached 5 m, length - up to 14 m, and weight - up to 5 tons or more. The meter-long skull of this bloodthirsty lizard, flattened on top and on the sides, had a huge mouth armed with fifteen-centimeter teeth.

In the Late Cretaceous period, there was also a nine-meter Gorgosaurus. Outwardly, it resembled a tyrannosaurus, but weighed about a ton or a little more. In its monstrous mouth there were 60 sharp ten-centimeter teeth. Scientists suggest that Gorgosaurus was clumsy, and therefore probably a poor hunter. The most accessible food for him could be slow animals, carrion and the remains of meals of other predators.

Even larger (14m or more in length, 6m in height) was the Tarbosaurus (“terrifying lizard”), also similar in appearance to a tyrannosaurus.

Albertosaurus (length 9m, weight 2.5t) and Megalosaurus (length up to 9m, weight 1t) were not inferior to these dinosaurs in bloodthirstiness.

One of the most terrible predators Cretaceous period there were dromaeosaurs, or raptors. They were distinguished by a huge sickle-shaped claw on each hind leg. They hunted in herds, so they could attack animals larger than themselves. Before biting the victim, raptors used grasping arms and long claws on their legs.

The most ancient raptor was Velociraptor, which lived in the Late Jurassic period. Its length was from one and a half to 4 m, weight up to 100 kg. Its sickle-shaped claw reached 15 - 20 cm. Deinonychus (“terrible claw”) had similar claws. Its height did not exceed one and a half meters, and its length was 3 -4 m. The average weight of these lizards was 70 -80 kg. The largest of this group was Utahraptor (“Utah Snatcher”), which lived in the Early Cretaceous period. It reached 6 m in length and weighed about 900 kg. Towards the end of the age of dinosaurs, in the Late Cretaceous period, some raptors became increasingly bird-like. This is reflected in their names: avimim (“imitating a bird”), strutomim (“imitating an ostrich”), dromshcheomim (“imitating a chicken”). They could eat not only meat, but also fruits and soft parts of plants, and also caught insects. Instead of teeth, they had keratinized jaws. And oviraptor (“egg stealer”) had only one tooth for splitting the shells of large mollusks, the meat of which it ate. A bone appeared on the wrist of these lizards, thanks to which raptors could move their forelimbs to the sides, just as birds spread their wings. These long-legged animals apparently ran faster than other dinosaurs and were still predators. For example, the Troodon (“tearing teeth”) had large eyes and keen hearing. Apparently he was a good hunter. Ostrich-like dromaeosaurs were an intermediate link between Archiopteryx and birds.

Dinosaurs are huge lizards, the height of which reached a 5-story building. Their remains are found deep in the earth, which is why scientists say that dinosaurs lived on Earth millions of years ago.

The last dinosaurs went extinct about 65 million years ago. And they appeared 225 million years ago. Judging by the remains of the bones of these lizards, scientists conclude that there were more than 1000 varieties of such animals. Among them were large and medium-sized, bipedal and quadrupedal, as well as those that crawled, walked, ran, jumped or flew in the sky.

Why did these giant animals become extinct? There are several theories about their death.

Since the death of dinosaurs occurred a very long time ago, we can only build hypotheses based on known scientific facts:

• The extinction of the dinosaurs proceeded very slowly and took millions of years. This period was called “glacial” by paleontologists.
• Over the course of these millions of years, the climate has changed.

  In the previous era, there were no ice caps on Earth, and the water temperature at the ocean floor was +20ºC. Climate change has caused a decline general temperature and the appearance of significant icing.

• In addition to climate, the composition of the atmosphere changed. If at the beginning of the Cretaceous period the air contained 45% oxygen, then after 250 million years it was only 25%.
• During this period of time, a planetary catastrophe occurred. It is confirmed by the presence of iridium, an element that is located deep in the earth’s core and is also found in asteroids and comets. Iridium is found in deep layers of soil throughout the planet.
• There are indirect witnesses of the collision of the Earth with an asteroid - huge craters. The largest are in Mexico (80 km in diameter) and at the bottom of the Indian Ocean (40 km).
• Along with dinosaurs, some species of lizards (sea and flying) became extinct.

When and how dinosaurs went extinct: theories of disaster

Habitat change

Our planet is changing very slowly but steadily. The climate is changing, new species of animals appear and old species disappear. They find themselves not adapted to life in new conditions.

Cold snap

The average air temperature dropped from 25ºC to +10ºC. The amount of precipitation has decreased. The climate has become colder and drier. Dinosaurs, like other lizards, were not adapted to life in cool conditions.

It is known that most lizards are cold-blooded. When the air temperature drops, they cool down and become numb. However, this theory cannot explain why those reptiles that were warm-blooded and could hibernate became extinct.

Another theory is more viable - as a result of climate change, there is less grass vegetation - ferns, which were eaten by non-predators. Judging by the size of dinosaurs, they needed substantial thickets of food to feed them. As a result of a decrease in the amount of food, gradual extinction began. Herbivores died because they lost food. And the carnivores - because there were few herbivores (which they ate).

Planetary catastrophe: collision with an asteroid or explosion of a star

Traces of collision with celestial body discovered on the island of Yucatan - a huge crater covered with stones and soil. When the asteroid collided with the earth, a powerful explosion should have occurred, which would have lifted tons of soil, stone and dust into the air. The dense suspension blocked the sun for a long time and caused a cold snap. As a result, not only dinosaurs, but also a number of other reptiles became extinct. This theory is confirmed by the remains of iridium in the soil of the Cretaceous period.

The explosion of a star relatively close to our planet could be the cause of a significant increase in radiation. However, it is not clear why the colossal emissions of radiation left other animals alive. Why dinosaurs became extinct still remains a mystery that haunts the minds of scientists.

Despite many theories, scientists are making computer simulations and reconstructions of what happened many millions of years ago. This is what the film will talk about.

Who are dinosaurs?

» Dinosaurs » Who are dinosaurs?

Word "dinosaur" literally means "terrible, huge lizard." Dinosaurs are ancient prehistoric reptiles that belong to the subclass of archosaurs. Dinosaurs are very different: they could be the size of a cat and the size of a huge whale, which is the largest animal on planet Earth.

Some dinosaurs were predators, i.e. hunted others, weaker and less aggressive. Other lizards ate exclusively plant foods. They are called herbivores. Dinosaurs conquered more than just land. They lived in water and, as many scientists believe, could fly.

Dinosaurs are not reptiles in the full sense, i.e. have a significant difference from them: the legs of dinosaurs were located directly under their torso, in contrast to reptiles, whose legs are located on the sides of the torso. In this regard, dinosaurs are similar to mammals.

The word “dinosaur” was first introduced into scientific use by the 19th century English explorer Richard Owen. He determined that the fossilized remains belonged to animals of the same species.

Dinosaurs lived on planet Earth for approximately 140 million years. They lived on all continents: on land and in the ocean. The era of dinosaurs is called the Mesozoic era. This era is divided into three periods: Triassic, Jurassic and Cretaceous. Dinosaurs arose during the Triassic period approximately 300-200 million years ago. Interestingly, then all the continents were connected to each other, and weather were hot. There was little vegetation. Huge areas of land resembled deserts. Plants grew in river valleys. Met and coniferous forests. The dominant plants were ferns and coniferous trees.

Dinosaurs reached their greatest prosperity during the Jurassic and Cretaceous periods.

At this time, they settled on land and learned to fly.

The dinosaurs resembled lizards of different sizes: some were the size of chickens, others were larger than elephants and whales. Dinosaurs were oviparous and differed from reptiles in that they laid their eggs on land rather than in water. Baby dinosaurs hatched from eggs fully formed and ready to full life. An example would be the young of modern crocodiles.

Dinosaurs gradually adapted to different natural conditions. Some became predators, others ate exclusively plants. Dinosaurs crawled and ran, lived in forests and deserts. There were several groups of dinosaurs. One of them consisted of animals that were very similar to modern crocodiles. These dinosaurs were called thecodonts. They lived near bodies of water and hunted insects, frogs and small lizards. Over time, thecodonts learned to run on their hind limbs. This made it possible to develop greater speed and, therefore, hunt more efficiently. Thecodonts began to dominate other lizards. Thecodonts are considered the ancestors of all dinosaurs.

Thecodonts include crocodiles, pterosaurs (lizards that could fly) and some dinosaurs themselves.

Thus, the term “dinosaurs” refers to all fossil lizards, regardless of their belonging to a particular order or group.

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Dinosaurs This very word has a fascinating effect on us. We immediately imagine prehistoric animals. Extraordinary giant monsters capture our imagination. Information in the press, dinosaurs in various forms on colorful illustrations and postcards, exhibitions with moving dinosaurs - all this brought these animals closer to us. However, no one can say with complete certainty what their color actually was or what they ate, because people have never seen dinosaurs with their own eyes. The last dinosaurs went extinct 65 million years ago. Only a few traces of their presence on Earth have survived to this day: fossilized bones and eggs, prints of the skin and feet of these reptiles.

Despite the painstaking work of scientists, there are many blank spots in our knowledge about dinosaurs. I was interested in the question “Why did the dinosaurs disappear?”

About 150 million years ago the Earth was inhabited by strange creatures, which we call dinosaurs. At that time, people did not yet exist, however, we know a lot about dinosaurs thanks to their bones found in rock strata.

Anna McCord, Fellow, British Museum of Natural History, London, England.

The time period of the existence of dinosaurs includes three prehistoric eras: the Triassic, Cretaceous and Jurassic periods (see glossary). Throughout these periods, dinosaurs reigned supreme on land. The era of dinosaurs began in the mid-Triassic, 230 million years ago. At that time, the continents were shifted and formed a single whole. During the Jurassic period, 210-145 million years ago, the continents gradually moved apart, and shallow seas formed between them. During the Cretaceous period, 145-65 million years ago, the continents moved apart more and more, the seas between them became deeper. This was the last period of the dinosaurs' existence.

After analyzing scientific data on the existence of dinosaurs, we can say that dinosaurs dominated our planet for 150 million years.

Dinosaur habitat.

Scientists believe that the continents were once connected into one continent, called Pangea. During the Triassic period, this huge island. Its name means “solid land.” The climate during this period was hot and dry. Ferns and horsetails grew in the damp lowlands in river valleys and along the ocean coasts, and trees and conifers grew in the forests. Animal world was represented by insects, frogs, and numerous lizards. The first representatives of dinosaurs were bipedal predators of medium size, then herbivorous dinosaurs on four legs appeared.

During the Jurassic period, Pangea split into two parts: Laurasia in the north and Gondwana in the south. Then Gondwana split into large pieces - territories South America, Africa, India, Australia and Antarctica. Gondwana and Laurasia were separated by the Tethys Sea. Perhaps the Mediterranean is what's left of it. The climate became humid and warm, and vast areas were covered with lush vegetation, especially diverse forests. Favorable environmental conditions contributed to the unprecedented flourishing of the world of dinosaurs: numerous new species arose that spread throughout the Earth. Of the living creatures on land, dinosaurs now dominated everywhere, and not other lizards.

During the Cretaceous period, the first continents broke away from Gondwana. The seas between the continents became wider and deeper, and the climate became a little cooler. This led to the emergence of regions with rich flora, in which new changes took place. Flowering plants appeared. The very first flowers were magnolias, then roses appeared. Next are birches, poplars, plane trees, oaks, changing their appearance at different times of the year. Palm trees, papyri, water lilies grew, cereal crops. Ponds became the habitat of the first birds. They were aquatic birds with webbed feet and sometimes even toothy ones. The first insectivores and marsupials, such as the opossum, appeared. No larger than a large rat, it was similar to animals that still live in Australia to this day.

Thus, during the time of dinosaurs there was rich vegetation. Also, some species of plants and animals have survived to the present time.

Types of dinosaurs.

Dinosaurs are a group of reptiles that lived many millions of years ago. Paleontologists have managed to discover fossils that can be used to judge the appearance and lifestyle of these animals. The word "dinosaur" itself means "terrible lizard." There were a huge number of dinosaur species on Earth, but not all of them lived at the same time.

Scientists have described over 500 different species of dinosaurs. There are large and small predatory dinosaurs, bird-footed and thick-headed dinosaurs, spiny, armored and horned dinosaurs. The largest family consisted of carnivorous dinosaurs. The smallest ones are spiny dinosaurs. There was a whole “arms race” between carnivorous and herbivorous dinosaurs. For example, herbivorous ankylosaurs resembled crawling tanks. Their body was completely covered with horny scales and plates, often merging into a solid shell. The huge herbivorous iguanodons had large toes on their front paws that resembled sharp daggers. On the backs of stegosaurs there was a series of bony plates that protected their spine. Triceraptors had three long horns. Larger lizards survived the fights. For example, the length of the Brontosaurus reached 20 meters, and its weight was about 40 tons. Among the predatory dinosaurs there were small and fast-running species that could attack large lizards in a pack. Ornithomimus was similar to modern ostriches. There were swimming dinosaurs. They are called ichthyosaurs (fish-lizards). Plesiosaurs had the head of a crocodile and the body of a whale with four legs. There were flying dinosaurs - pterosaurs. With their leathery wings they resemble modern bats. Some ancient species - turtles, crocodiles, lizards - live on our planet today, having hardly changed in 300 million years.

Thus, the world of dinosaurs was very diverse. Dinosaurs looked very strange to our eyes. That's why I'm so curious to explore their world.

5. Conditions for the existence of dinosaurs.

A dinosaur is a living organism. For its existence, certain conditions are necessary: ​​climate, the presence of a feeding and breeding environment. The climate of our planet during this period was favorable for the existence of dinosaurs: warm and mild. Dinosaurs mastered land, water and air. They had a huge planet at their disposal. Vegetable world was quite rich and varied. All plants were available to feed dinosaurs, from low-growing ferns to giant trees. Carnivorous dinosaurs had long and sharp claws with which they finished off their prey. And also with sharp teeth, tearing prey into pieces.

Herbivorous dinosaurs had to look for ways to protect themselves from predators. Many species of dinosaurs led a gregarious lifestyle. This gave them protection from enemies. But carnivorous dinosaurs did not only feed on their herbivorous relatives. They also hunted small animals - insects and lizards. There was no shortage of food for dinosaurs of any kind.

Scientists have proven that dinosaurs laid eggs. The cubs could remain in the nest for a long time under the protection of the mother who fed them. The cubs lived in the nest with their parents until a certain age. Thus, dinosaurs exhibited nestling and brood behavior among young animals that were cared for by females.

The lifespan of dinosaurs varied: from 10-20 years in some species to 300 years in others. Therefore, dinosaurs could raise more than one offspring during their lives.

So, the conditions for the existence of dinosaurs were: soft and warm climate, the presence of diverse flora and fauna, caring for their offspring.

6. Reasons for the extinction of dinosaurs.

For 150 million years, dinosaurs dominated our planet and then disappeared. This happened at the end of the Cretaceous period 65 million years ago. Ever since dinosaurs were discovered, scientists have been puzzled by the question of why dinosaurs disappeared so suddenly. Many hypotheses have been put forward on this matter.

There is a hypothesis about a global flood that took the lives of dinosaurs. I do not agree with this hypothesis, because...

Marine animals (plesiosaurs, ichthyosaurs) also became extinct. They could survive in the conditions of a global flood.

I also think the hypothesis about the extermination of dinosaurs is incorrect primitive man. It has already been proven that primitive people appeared 60 million years ago, and by that time dinosaurs no longer existed.

Some scientists have suggested reasons for the death of dinosaurs such as enormous growth and clumsiness. But both the smallest and fastest dinosaurs became extinct.

I consider the assumption that predatory dinosaurs destroyed herbivores and then themselves died of starvation to be incredible.

Why didn’t predatory dinosaurs touch other reptiles that have survived to this day?

Most unpopular in scientific world version explains the disappearance of dinosaurs by the emergence of new “hungry” predators - the first mammals that may have feasted on dinosaur eggs and the dinosaurs themselves.

Let's assume that a huge celestial body with a diameter of 10 kilometers fell to Earth. The impact kicked up a large amount of dust, ash and dirt, and the skies over the entire Earth darkened for many months. Plants that needed sunlight died. Then herbivores and predators died. There was a cold snap, because... Sun rays earth's surface didn't reach. The upper layers of the air warmed up, and warming set in again. If some species of dinosaurs managed to survive the disaster, they still died as a result of its consequences. The consequences lasted for years, and perhaps centuries. Living conditions gradually deteriorated. Dinosaurs were adapted to warm and humid climate and rich flora and fauna. As a result of a terrible catastrophe, they lost all this. Cold nights and winters adversely affected the breeding of offspring. The cubs grew more slowly individual species dinosaurs became more rare and gradually began to die out.

Scientists have proven that a collision with a huge celestial body (comet, meteorite or asteroid) can have devastating consequences and threaten the lives of billions of species of creatures. I believe that a meteorite impact could have significantly disrupted the conditions of existence of dinosaurs and caused the process of their extinction. Therefore, this hypothesis seems to me the most truthful.

7. Conclusion.

Having found out the time period of existence of dinosaurs, determined their habitat, and studied the conditions of existence of dinosaurs, we can conclude that possible reasons oh the death of these animals. Of all the existing hypotheses about the disappearance of dinosaurs, I think the most correct is the hypothesis about the disappearance of dinosaurs due to a meteorite collision with planet Earth.

Life on Earth arose about 3000 million years ago. It started with tiny single-celled creatures. Then other life forms began to appear. But dinosaurs populated the planet only 200-230 million years ago. Scientists to this day put forward various theories regarding how dinosaurs appeared, and it is not known which of them is correct.

Ancient world

Different types dinosaurs lived on earth in different time: some species died out, others appeared. In general, the era of these creatures lasted more than 150 million years. If we compare the time of human existence with this period, we live only 200,000 years. By official version, people and dinosaurs lived in different eras, but rock paintings and various archaeological finds cast doubt on this version.

The word "dinosaur" itself means a terrible or terrible lizard. These creatures were cold-blooded and needed a lot of sunlight. The official version of how dinosaurs came to be says that these creatures evolved from reptiles that lived on the planet before them. The ancestors of dinosaurs lived both on land and in water. They are called archosaurs - ancient lizards. They looked like amphibians and ate plant foods. Ancient lizards had lungs and laid eggs on land. Gradually, reptiles became larger, although the first dinosaurs were small, the size of a chicken. Some species remained this way throughout their existence. Other species became large, they increased in size and became stronger. This is how dinosaurs appeared, which changed and improved over millions of years, populating the Earth.

Ancestors of dinosaurs

So how did dinosaurs come about, who did they come from? It is generally accepted that all dinosaurs descended from thecodonts. These creatures were of various sizes: small, large, medium. They walked on four legs, and some walked on two. It was from them that the first dinosaurs came.

A distinctive feature of thecodonts is that they had special structure skeleton: the place of articulation of the hip and pelvis was such that this type of reptile could move on two legs.

World domination

After dinosaurs appeared, they began to evolve. Gradually, these creatures took over the Earth, becoming the real rulers of the land. Their success in survival lay in the fact that they had a unique evolutionary flexibility and could also eat a wide variety of foods. Dinosaurs could also walk on two legs, which allowed them to cover vast distances. As soon as new living conditions were formed, dinosaurs immediately adapted to them. Because of this feature, new species began to appear: herbivores, carnivores, omnivores. There were giants and there were small individuals. Some creatures grew wings and began to fly.

Secrets of the Age of Dinosaurs

Where dinosaurs came from remains a mystery, as does their demise. Another mystery - did these creatures live in the same era as people or did they become extinct before the advent of humanity? According to scientists, the eras of people and giants differed, although archaeological finds in the form of rock paintings indicate the opposite. Fairy tales and legends of the peoples of the world that talk about ancient lizards and people remain doubtful.

In the sixties of the twentieth century, burials of the pre-Inian period were found in Peru. The stones depicted people and dinosaurs living closely together. This discovery contradicts the official theory of evolution. The stones found depicted a sauropod with spines. Scientists only learned that this creature has spines in the nineties. In addition to the found drawings on stones, the Bible speaks about the existence of humans and dinosaurs in the same era, albeit indirectly. Scientists also found human traces next to dinosaur tracks. And all this remains a mystery, since according to the accepted version, people and dinosaurs lived millions of years apart, but judging by the finds, this is not so.

Dinosaurs are someone's ancestors

If giants evolved from ancient reptiles, then who descended from dinosaurs, what are the inhabitants of the planet?

Modern animals have some similarities with the ancient inhabitants of the Earth, but only a small part are considered their descendants. During the Jurassic period, Archeopteryx lived, which became the ancestor of birds. Scientists have found many similarities between birds and this type of dinosaur: the presence of scales, the structure of the limbs, and the method of reproduction. The direct ancestors of birds are considered to be Deinonychus, Compsognathus and Struthiomimus, although appearance this cannot be said.

Mammal Ancestors

After the dinosaurs disappeared, mammals began to develop. Initially they led night look life, settled, constantly developed. From them came modern mammals. For example, once upon a time didelphodons lived on Earth, which had bags. They are similar to modern opossums. The ancient Erythrotherium had the ability to climb trees. This creature is considered the ancestor of monkeys.

Types of dinosaurs

All known species of dinosaurs are divided into two large orders: ornithischians and lizards. These units have their own classifications. Thus, there are groups of aquatic, flying, herbivorous, carnivorous dinosaurs and some others. Where did dinosaurs come from and why were they divided into groups?

Since scientists began to find the remains of aquatic representatives, the question has arisen: how are dinosaurs of this group born? Those that move on land, fly, usually lay eggs, and aquatic reproduction occurs either by the creature coming onto land to lay eggs, as modern turtles do, or there were other methods of reproduction.

Among aquatic inhabitants, the most unusual are:

1. Pliosaur. It is considered a predator and ate everything it saw. This creature had no enemies, which is why it attacked first.
2. Ichthyosaur. The first remains of these creatures were found in Russia, but most of the finds were in Germany. These lizards lived in packs, so they could easily repel enemies, and it was easier for them to get food.
3. Mosasaurus. The remains of these saurs have been found all over the planet, even in cold Antarctica. It is believed that monitor lizards originated from this species. The mosasaurus lived in water, moved like a snake, like sea ​​eels.
4. Elasmosaurus. It is considered an unusual predator that could hunt from any distance. This dinosaur easily caught any prey, even the fastest.
5. Shonisaurus. Among aquatic reptiles, this creature is considered the largest. It ate squid, shellfish, and some types of octopus.

These are not all representatives water world who inhabited the planet millions of years ago.

Flying species include pterosaur, archeopteryx, pterodactyl, and ornithocheirus. Some of them reached the size of a small airplane.

The most popular predatory dinosaurs are Tyrannosaurus, Megalosaurus, Spinosaurus, Tarbosaurus, Giganotosaurus, Velociraptor.

Representatives of herbivores are Stegosaurus, Brachiosaurus, Diplodocus, Brontosaurus, Triceratops, Iguanodon.

Why did they become extinct?

Scientists still can't say for sure where dinosaurs came from, but an even bigger mystery is why they went extinct. This happened about 60 million years ago, during the Cretaceous period. At the same time as the giants, marine reptiles, flying representatives, some species of mollusks, and algae became extinct. Scientists estimate that during that period, about 20% of land vertebrates and about 15% sea ​​creatures. The most common theory for this phenomenon is that a meteorite fell in the Yucatan region of the Mexican peninsula.

There are other versions of the reason for the extinction of dinosaurs, including high volcanic activity. About 6 million years ago there was a strong eruption with a gigantic outpouring of magma.

Other scientists suggest that the extinction was caused by the destruction of clutches of eggs, the young first predatory mammals. The possibility of extinction due to a sharp drop in the level of the World Ocean, changes in magnetic field Earth.

Scientists from the University of Reading have put forward a different theory, according to which dinosaurs were already dying out even before the meteorite fell. In their opinion, the extinction caused the emergence of other species. Scientists have assessed the extinction of several thousand dinosaur species. As a result of the work, it was possible to find out that the rate of appearance of new species and the rate of disappearance of old ones are interrelated. And about 80 million years ago, some of the giant species died out, and in their place new creatures appeared inhabiting the planet.

Dinosaurs (from the Greek dinosauria, deinos - “terrible” and saurus - “lizard”) lived in Mesozoic era, which is divided into three periods: Triassic, Jurassic and Cretaceous. Over the entire history of studying the remains of ancient lizards, paleontologists have been able to identify and describe over 500 different species of these reptiles.

Where and in what territories ancient lizards lived, see the infographics of AiF.ru.

When did the first dinosaurs appear?

The first dinosaurs, archosaurs, appeared 230 million years ago. Typical representatives of the Triassic period were Placerias, Plateosaurus, Coelophysis, Cynodont, and Petheinosaurus. What dinosaurs lived in Russia from the Triassic to Cretaceous periods,

During the Jurassic period, when the Earth established temperate climate, flying lizards appeared (Archaeopteryx, pterodactyl, pterosaur), as well as predatory dinosaurs large sizes(stegosaurus, diplodocus, anurognathus, allosaurus, ankylosaurus and others). The remains of some of them are paleontologists.

During last period During the Mesozoic era, giant lizards lived on Earth, many of them reaching 5–8 meters in height and 20 meters in length. Typical reptiles of the Cretaceous period: Velociraptor, Seismosaurus, Tyrannosaurus, Iguanodon and Culasuchus.

What dinosaurs lived in Russia during the Mesozoic era?

How long did dinosaurs live?

Paleontologists believe that the lifespan of small species ranged from one to two decades, and large dinosaurs could live from 200 to 300 years.

Who inhabited the Tula region 300 million years ago,

Why did dinosaurs become extinct?

The changes that occurred on Earth at the end of the Cretaceous period led to the gradual extinction of all types of dinosaurs. Possible reasons for the disappearance may include the following:

• an asteroid that fell to Earth;
• sudden warming and climate change;
• a strong earthquake or volcanic eruption;
• an increase in the number of mammals that ate food familiar to dinosaurs.

What marine animals lived on the territory of Russia in ancient times,

When were dinosaur bones first discovered?

The first dinosaur skeleton was described in the 1820s by British paleontologist William Buckland.

When was the last time a dinosaur was discovered on Russian territory?

Last thing significant discovery was made in 2014. During the extraction of shale, an almost intact skeleton of an ichthyosaur was discovered.

How many mysteries are hidden in the ancient The World History. Dinosaurs are one of them. They reigned on Earth for more than 160 million years, from the Triassic period (approximately 225 million years ago) until the end of the Cretaceous (about 65 million years ago). Today, scientists can recreate the appearance of these animals, their lifestyle and habits, but many questions have not yet been answered. How did dinosaurs appear? Why did they disappear? Although these dinosaurs disappeared from the face of our planet almost 65 million years ago, the history of dinosaurs, their emergence, life and sudden death is of undoubted interest to researchers. Let's look at the main stages of reptile development.

origin of name

Dinosaurs are the name given to the only group of reptiles. This name applies only to those of them who lived in the Mesozoic era. Translated from Greek, the term “dinosaur” means “terrifying” or “terrible lizard.” The name was introduced by British explorer Richard Owen in 1842. This is how he proposed to name the first discovered fossilized remains of ancient lizards in order to emphasize their unprecedented size and grandeur.

Beginning of the Age of Dinosaurs

As you know, the entire history of the planet is traditionally divided into successive eras. The time in which dinosaurs lived is usually referred to as the Mesozoic. It, in turn, includes three periods: Triassic, Jurassic and Cretaceous. began about 225 million years ago, and it ended about 70 million years ago. The history of dinosaurs begins during the first period - the Triassic. However greatest distribution they got in the chalk.

Long before the emergence of dinosaurs, reptiles lived on the planet. They looked like the usual ones to modern man lizards in that their paws were on the sides of their bodies. But when did it start global warming(300 million years ago), an evolutionary explosion occurred among them. All groups of reptiles began to actively develop. This is how the archosaur appeared - it differed from its predecessors in that its paws were already located under the body. Presumably, the emergence of dinosaurs dates back to this chronological period.

Dinosaurs of the Triassic period

Already at the very beginning of the Triassic period, many new species of lizards appeared. It is believed that they already walked on two legs because their front legs were shorter and much less developed than their hind legs. This made them different from their predecessors. The history of dinosaurs says that one of the first species was the Staurikosaurus. He lived approximately 230 million years ago in what is now Brazil.

At the early evolutionary stages, there were other reptiles: aetosaurs, cynodonts, ornithosuchids and others. Therefore, dinosaurs had to endure a long rivalry before finding their niche and flourishing. It is generally accepted that they acquired a dominant position over all other inhabitants of the planet at the end of the Triassic period. This is associated with the large-scale extinction of animals that inhabited the Earth at that time.

Dinosaurs of the Jurassic period

By the beginning they became the absolute masters of the planet. They settled across the entire surface of the Earth: in the mountains and plains, swamps and lakes. The history of dinosaurs of this period is marked by the appearance and spread of numerous new species. Examples include Allosaurus, Diplodocus, and Stegosaurus.

Moreover, these lizards were very radically different from each other. So, they could be completely different sizes and have different lifestyles. Some of the dinosaurs were predators, others were completely harmless herbivores. It is interesting that it was during the Jurassic period that winged lizards - pterosaurs - flourished. Majestic reptiles reigned not only on land and in the sky, but also in the depths of the sea.

Dinosaurs of the Cretaceous period

During the Cretaceous period, the number and diversity of dinosaurs reached its maximum level. On the other hand, some scientists do not share the view of the sudden and significant increase in the number of reptiles. In their opinion, representatives of the Triassic and Jurassic periods are much less studied than the inhabitants of the Cretaceous.

At this time there were a lot of herbivorous reptiles. This is due to the appearance on the planet large quantity new plant species. However, there were also plenty of predators. The emergence of such a famous species as the tyrannosaurus dates back to the Cretaceous period. By the way, he turned out to be perhaps one of the most famous dinosaurs. The most massive of all carnivorous reptiles, it weighed up to eight tons, and its height could reach 12 meters. Also dating back to the Cretaceous period is the appearance of such known species, like Iguanodon and Triceratops.

Mysterious death of dinosaurs

Dinosaurs disappeared approximately 65 million years ago. This event happened at the very end. Today there are many different theories about how and why this happened. At the same time, scientists still cannot come to a consensus.

In particular, questions arise about the reasons for their death, as well as whether it was slow or fast. What is known for certain is that it became one of the parts of the “great extinction” of that time. Then not only dinosaurs disappeared from the face of the Earth, but also other reptiles, as well as mollusks and some algae. According to one point of view, the “great extinction” was triggered by

After this, gigantic clouds of dust rose into the air, blocking the sun for months, which caused the death of all living things. Some scientists are of the opinion that a star exploded not far from the Earth, as a result of which the entire planet was covered with radiation fatal to its inhabitants. Another common point of view is that dinosaurs became extinct as a result of cooling that began at the end of the Cretaceous period. One way or another, the era of reptiles is over. How this happened, science has yet to find out.

History of dinosaur studies

The history of dinosaurs began to interest people relatively recently. Their study began only at the beginning of the 19th century. This is largely due to the fact that people did not perceive the bones found in the Earth as dinosaur tracks. Interestingly, in antiquity they believed that these were the remains of heroes from the Trojan War.

In the Middle Ages and until the 19th century - giants who died in Only in 1824 were they first identified as the remains of giant lizards. In 1842, the British scientist Richard Owen, drawing attention to the main features these reptiles, brought them into a separate suborder and gave them the name “dinosaurs”. Since then, there has been a constant accumulation of knowledge about them, and new species have been discovered. The life history of dinosaurs was becoming more and more complete. Now the study of these reptiles continues with even greater diligence. Modern researchers count almost a thousand species of dinosaurs.

Dinosaurs in popular culture

World art has given people a huge number of books and films dedicated to these lizards. For example, they appear in Arthur Conan Doyle's The Lost World, which was subsequently filmed several times. Based on his creativity, the famous film “Jurassic Park” was filmed. The history of dinosaurs for children is presented through numerous animated films and colorful illustrated books. From them, a child can get acquainted with these amazing and majestic animals.

Despite the fact that so much time has passed since the last dinosaurs disappeared from the surface of the Earth, the history of the origin of these majestic lizards, their life and the mystery of their disappearance still excites the hearts and minds of people. However, most of their mysteries will most likely remain unanswered.