What kinds of dinosaurs are displayed in Beibei Dinosaur Museum?

(1) Lei Long: Some dinosaurs were very huge, such as Lei Long. During the Jurassic period, the climate on the earth was warm and humid, and there were lush forests everywhere. Because of these rich plant foods, herbivorous dinosaurs flourished. After that, Lei Long was also active in the North American Plain. Lei Long weighs about 35 to 50 metric tons and has thick legs like a trunk. Long neck, standing as high as seven stories, can be said to be the largest animal in the world. Although Lei Long's body is surprisingly large, her temperament is very gentle. She usually feeds on plants in temperate forests and sometimes walks into swamps. Because of the buoyancy of water, she can reduce the heavy burden on her body and avoid the attack of fierce carnivorous dinosaurs like Allosaurus. (2) Three brachiosaurus: Bone plates and fragments on Stegosaurus and Ceratosaurus can only be used for passive defense and cannot fight back. It was not until Chironomid Dragon appeared that the situation gradually changed. Lei Long is the largest of all sauropods. It has two spear-shaped horns on its head, and the other horn protrudes between its eyes and nostrils. Such a sharp weapon, even the most terrible carnivorous dinosaur will give it three points. (3) Stegosaurus:10.5 billion years ago, stegosaurus was characterized by two ribs on its back and spikes on its tail. Stegosaurus was a herbivorous dinosaur and moved slowly. Its bone plate and spikes on its tail became the best weapon against carnivorous dinosaurs. (4) Ankylosaurus: Stegosaurus was protected by a bone plate, but it was still very fragile where the bone plate could not cover it. When stegosaurus gradually disappeared, Ankylosaurus (armadillos) covered with bone plates took its place. Ankylosaurus is like an invincible tank car, even Tyrannosaurus Rex can't help it. (5) Tyrannosaurus Rex: Tyrannosaurus Rex is the largest and most ferocious carnivorous dinosaur. Tyrannosaurus rex appeared in the last stage of the dinosaur era, about 80 million years ago. Tyrannosaurus rex's body is 14 meters high and weighs about 10 metric ton. Its hind feet are thick and strong, and can even support a rhinoceros. From the fossils of Tyrannosaurus Rex, it is found that every tooth is as big as an adult's palm, and even its eyes are bigger than a human head. Although most of the body is surprisingly large, the forelimbs of Tyrannosaurus rex are so small and short that it is impossible to put food in its mouth. The killer dragon has the same habit as Tyrannosaurus Rex, and it is a fierce animal. Since ancient times, there have been different opinions about the real cause of dinosaur extinction, but there is no definite statement, so it is still an unsolved mystery. Only some well-known statements are described here as follows: 1. Meteorite collision theory: 1980, American scientists found high concentration of iridium in the stratum 65 million years ago, and its content exceeded the normal content by dozens or even hundreds of times. Therefore, scientists linked it to the extinction of dinosaurs. According to the content of iridium, it is calculated that the impact object is an asteroid with a diameter of 10 km. Such a large meteorite hit the earth, which is definitely an unparalleled blow. According to the earthquake intensity, it is about Richter scale 10. The crater produced by the impact will be more than 65,438+000 kilometers in diameter. It took scientists 65,438+00 years to finally get the preliminary results. They found this crater in the stratum of Yucatan Peninsula in Central America. According to the calculation, the diameter of this crater is between180km and 300km. Now, scientists are still doing further research on this big pit. _ _ _ Scientists began to describe the heroic scene 65 million years ago for us. One day, dinosaurs were still eating and drinking in paradise on earth, and suddenly a dazzling white light appeared in the sky. A boulder with a diameter of 10 km fell from the sky. It is an asteroid with a speed of 40 kilometers per second. The seabed was knocked out of a huge pit, and the seawater was rapidly gasified, and the steam was sprayed into the sky for tens of thousands of meters. Then the tsunami was as high as 5 kilometers and spread at an extremely fast speed. The turbulent sea swept everything that landed on land, and the turbulent waves swept the earth's surface, and then met at the back end of the impact point, where the huge sea power triggered a strong volcanic eruption on the Deccan Plateau. At the same time, it changed the movement direction of the earth's plates. What a terrible disaster this is. Meteorites hit the earth and produced overwhelming dust, polar snow melted, plants were destroyed and volcanic ash filled the sky. For a time, it was dark and the temperature plummeted. Heavy rain, flash floods and mudslides swept away the dinosaurs and buried them. In the next few months or even years, the sky is still full of dust and clouds, and the earth is buried all the year round. The vast land was silent for a moment, thus ending an era in the history of biology. 2. Comet collision theory: Comet collision theory began with the argument that paleontologists David Laup and John Sepkowski published that the extinction of paleontology occurred every 26 million years. Louis Albalez handed this argument and his own theory to the astrophysicist-Charlie Murat La, who later thought that it was because of the gravity of the solar nemesis that comets were periodically pushed to the earth. 3. Orogenic movement: The orogeny at the end of Cretaceous dried up the swamp, and many dinosaurs whose home was the swamp could no longer survive. Because of the changes in the post-Qi Dynasty, plants also changed, and herbivorous dinosaurs could not adapt to new foods and died out one after another. The herbivorous dinosaurs became extinct, and the carnivorous dinosaurs also lost their dependence. As a result, they also became extinct. This extinction process lasted 65,438+0,000-20 million years. By the end of Cretaceous, it was extinct on the earth. 4. Climate change theory: Due to plate movement, ocean currents have changed, which has caused great changes in the climate. The cold climate killed plants and dinosaurs died for lack of food. 5. Volcanic fire: Due to volcanic eruption, a large amount of carbon dioxide is ejected, which impacts the global greenhouse effect and causes food death. Moreover, the volcano spewed fire, resulting in the release of a large amount of salt, the destruction of the ozone layer, harmful ultraviolet radiation on the surface, resulting in extinction. 6. Ocean ebb theory: According to Barker, when the ocean ebbs, when the land borders, creatures contact each other, which leads to the extinction of some species. Kangaroos, for example, can live in the island continent of Europe, but they will die if they meet other animals in South America. In addition to this relationship between eating and being eaten, there are also infectious problems such as diseases and parasites. 7. Warm-blooded animals say: Some people think that dinosaurs are warm-blooded animals, so they may not be able to resist the cold weather in the late Cretaceous and thus cannot survive. Because even if dinosaurs were warm-blooded, their body temperature was still not high, probably similar to that of living sloths, and to maintain such a body temperature, they could only live in a tropical climate. At the same time, the dinosaur's respiratory organs were not perfect and could not fully supplement oxygen. They don't have thick hair to avoid hypothermia, but they easily lose a lot of heat from their long tails and feet. The difference between warm-blooded animals and cold-blooded animals is that if the body temperature drops below a certain range, it will consume physical energy to raise the body temperature and the body will soon become weak. They are too big to go into caves to avoid the cold, so if the cold days last for a few days, they may freeze to death because of exhaustion. 8. Man-eating theory: Because of climate problems, a large number of flowers and plants are extinct, herbivorous dinosaurs that feed on herbivores gradually die, while carnivores die because of lack of food. 9. Oppression theory: The rapid increase in the number of dinosaurs led to the extinction of herbivorous dinosaurs with limited plants, and then carnivorous dinosaurs that ate herbivorous dinosaurs died because of lack of food. (Doubt: Why did dinosaurs suddenly increase after about 200 million years of ecological balance? The key to the establishment of this theory has also directly caused many scholars to review the reasons for the abnormal increase in dinosaur production. ) 10. the mammalian prisoner said: in the second half of Mesozoic, the ancestors of mammals already existed. According to fossil records, mammals at that time were very small and the number was very limited. It was not until the late Cretaceous that the number began to increase rapidly. It is speculated that they are omnivores whose main food is insects. These small mammals have been eating dinosaur eggs since they found them. 1 1. Species aging theory: It is believed that dinosaurs were too big because they had been breeding for hundreds of millions of years. Moreover, bones such as horns are also extremely developed, which causes great inconvenience to life and eventually leads to extinction. The most representative dinosaur brontosaurus is 25 meters long and weighs 30 tons. Because of his huge size, he lost his ability to survive. In addition, Triceratops and others also went to the road of self-destruction because of the increasing number of three horns and the unusually developed bones to protect their heads. My opinion: not all dinosaurs are so huge, but there are also small dinosaurs with a body length of only about one meter. In addition, there are dinosaurs with bones like deer that can run briskly. But why did this dinosaur die out at the same time? Moreover, in cold-blooded animals, abnormally developed bones and other parts are considered to be able to absorb external temperature and release internal heat to regulate body temperature, which has very favorable functions. Therefore, I suspect that the extinction of dinosaurs was due to the aging of species. ) 12. Alkaloid theory: This theory holds that flowering plants began to appear in the last period of dinosaur existence, that is, the Cretaceous period, and some of them contained toxic alkaloids. Dinosaurs died of poisoning from eating too much. Because mammals can distinguish poisonous plants through taste and smell, but dinosaurs don't have this ability. However, plants containing alkaloids did not suddenly appear in the late Cretaceous, but were already visible five million years before the extinction of dinosaurs. This theory can't explain why dinosaurs survived during this period. In addition to the above twelve statements, there are other less well-known statements, such as "infectious diseases", "radiation from the universe or supernova explosion", "not taking Noah's Ark" and "vibration theory of the solar system". As for which is the best statement, it depends on everyone's ideas, and there is no right or wrong. After all, the mystery of dinosaur extinction has not really been solved!