The cause of dinosaur extinction is controversial

In the 4.5 billion years of life on Earth, humans are now the undisputed “dominant species”. Although humans do not have any advantages over many species on Earth today, we have still gained a firm foothold on Earth with our smart minds. In this article we are studying about dinosaur extinction

Before humans came into being, the dominance of the Earth depended largely on the size of organisms, such as the dinosaurs that once lived on Earth for 160 million years. Although strictly speaking, dinosaurs also had smaller bodies, overall, their size was indeed their biggest advantage.

Earth’s former “dominant species”: dinosaurs

During the Triassic period, as the earth’s environment changed again, a new group of animals appeared on the earth. Initially, this group was herbivorous, and then gradually a carnivorous branch was born. They became the most powerful existence on the earth with their huge bodies.

By the late Triassic period, dinosaurs had become the dominant species on Earth, and their reign lasted for 160 million years until the fifth mass extinction at the end of the Cretaceous period, when they disappeared from the Earth.

Because the era was too far away, dinosaurs no longer existed after that, so humans learned about dinosaurs very late.

It was not until the 19th century that a British physician named Gideon Mantell discovered the Iguanodon, and since then, humans have begun to study dinosaurs.

These huge carcasses gradually aroused human interest. In the study of dinosaur fossils, people not only speculated the age of dinosaurs, but also conducted a comprehensive analysis of their appearance, habits, and species.

But the more people analyze it, the more confused they become. Such a species that has dominated the Earth for a long time should have also experienced the mass extinction in the late Triassic period. Why did it suddenly disappear after the end of the Cretaceous period?

Research on the extinction of dinosaurs

After research by scientists, it is generally believed that dinosaurs disappeared from the earth after the Cretaceous period.

First of all, most of the dinosaur fossil eggs found today are from the end of the Cretaceous period. The fact that dinosaur eggs have been preserved in the form of fossils indicates that they basically had no chance of reproducing offspring. And no fossils of either dinosaur fossils or dinosaur eggs have been produced since then.

Such discoveries have convinced people that dinosaurs were extinct after the advent of the Cenozoic Era. So what kind of experiences did such powerful dinosaurs go through, and who was the culprit that caused their extinction?

There are many speculations about the cause of the extinction of dinosaurs, and each one makes sense.

For example, the “space weather” theory proposed by German scientists . They believe that the extinction of dinosaurs was caused by strong particle flows in the universe. After these particle flows entered the earth, they had a great impact on the earth’s climate, making the living environment of dinosaurs increasingly harsh, and eventually became remains in the history of the earth.

Another example is the famous orogeny theory, which holds that crustal movement made it impossible for dinosaurs to adapt to the new environment, leading to their mass death.

Although people have indeed found fossils of dinosaur eggs under the clay layer at the end of the Cretaceous period, large-scale collective deaths cannot be affected by simple factors.

Scientists

What’s more, scientists have discovered a group of dinosaur cubs among dinosaur fossils. Judging from their remains, they were in extremely painful conditions. This forces humans to consider the cause of dinosaur extinction as some large-scale destructive factors, such as an asteroid hitting the earth.

This speculation is indeed the most mainstream understanding at present.

First, scientists found extremely high concentrations of iridium in strata dating back 65 million years , and the only thing that could match that concentration was a meteorite from the sky. Second, scientists calculated the size of the meteorite based on the concentration of iridium and found the existence of this meteorite crater.

In the Yucatan Peninsula of Mexico, scientists discovered a meteorite crater with a diameter of about 180 to 300 kilometers, and the iridium content around the crater is similar. This discovery has made it impossible to avoid the idea of ​​meteorites in discussions about the cause of the extinction of dinosaurs.

To this end, in 2009 , Chinese paleontologist Li Yang published a paper at Yale University, indicating that the extinction of dinosaurs was caused by an asteroid hitting the earth, which then caused volcanic activity on the earth.

As a result of the interaction between the two, dinosaurs became the biggest victims on Earth, and eventually disappeared from the Earth after a few months.

So, is the main cause of the Earth’s destruction really the legendary asteroid impact ?

New discoveries, new answers

Initially, scientists believed that the cause of the mass extinction of dinosaurs was an asteroid hitting the earth, but Chinese scientists detected that after the asteroid hit the earth, dinosaurs still survived on Earth for two million years.

This seems to indicate that, although we all believe that the end of the Cretaceous period was the last time for the dinosaurs, we do not know how long this time limit was. Rather than saying that the dinosaurs died out in an instant, it is better to say that there was a process of extinction.

Scientists speculate that dinosaurs had already begun to become unadapted to the environment long before the asteroid hit the Earth.

First, the atmospheric composition changed greatly during the Mesozoic Era. The dinosaurs lived in an era with a very high carbon dioxide content, which was more conducive to their survival.

But other creatures on the earth were also growing and reproducing. The emergence of the nourishing facility house caused the carbon dioxide to be gradually consumed. In addition, carbon dioxide began to be deposited underground. Such changes made dinosaurs begin to become uncomfortable with the earth’s environment.

Secondly, the earth’s crust was active at this time. Volcanic eruptions made it difficult for the huge dinosaurs to survive natural disasters; thirdly, the temperature also changed during this period.

Scientists have found that dinosaurs lived from the equator to the North Pole. Which means that the temperature of the earth should have been similar to that of the equator. But as the temperature dropped sharply. The living environment faced by dinosaurs became more and more harsh. Their discomfort with the environment became more obvious.

Living environment

Just as the dinosaurs were changing with the harsh living environment, a huge asteroid hit the Gulf of Mexico. This impact had a serious impact on the earth. Tsunamis, earthquakes, sudden temperature changes and other natural disasters struck again. That making the dinosaurs, who were in a vulnerable period, even worse.

After this, mammals that were better adapted to the environment were born. Dinosaurs increasingly lost their competitiveness and were gradually eliminated by nature.

It can be seen that the role played by the asteroid is more like a catalyst. Its arrival accelerated the extinction of the dinosaurs.

End

If it weren’t for the changes in the Earth’s environment, the dinosaurs wouldn’t have happened to encounter. The asteroid hitting the Earth during their vulnerable period.

Therefore, the reasons for the extinction of dinosaurs are diverse and complex. Including the challenges faced by internal survival and the threat posed by asteroids. Under the attack of multiple factors, dinosaurs also ushered in their doomsday.