The feeling of dinosaur extinction

Studying the extinction of dinosaurs is not only an academic issue, because we may encounter some kind of catastrophe in the future (in case a star hits the earth one day, we may know how to avoid such an impact). We need to know as much as possible about the impact of such incidents, and hope that we can take some emergency measures once faced with such incidents in the future.

There are many theories about the extinction of dinosaurs:

Asteroid impact theory: the asteroid hit the earth, and the earth was covered with gray, and the sunlight could hardly reach the ground. Many plants died one after another and the temperature began to drop. Dinosaurs died one after another because of low temperature and lack of food. It is a statement that most people agree with.

Climate change theory: 65 million years ago, the earth's climate suddenly changed and the temperature plummeted, which led to the decline of oxygen content in the atmosphere and dinosaurs could not survive. Some people think that dinosaurs were cold-blooded, without hair and warm organs, unable to adapt to the decline of the earth's temperature, and all of them froze to death.

Theory of Species Struggle At the end of the dinosaur era, the first small mammal appeared. These animals are rodent carnivores and may feed on dinosaur eggs. Due to the lack of natural enemies, more and more small animals finally ate dinosaur eggs.

Continental drift theory: geological research proves that there was only one continent on the earth when dinosaurs lived, and that was "Pangea". Due to the change of the crust, the Jurassic continent split and drifted, which eventually led to the change of environment and climate and the extinction of dinosaurs.

Geomagnetic change theory: Modern biology has proved that the death of some creatures is related to the magnetic field. When the earth's magnetic field changes, creatures sensitive to the magnetic field may lead to extinction. It can be inferred that the extinction of dinosaurs may be related to the change of the earth's magnetic field.

Angiosperm poisoning theory: At the end of the dinosaur era, gymnosperms on the earth gradually became extinct and were replaced by a large number of angiosperms, which contained toxins that gymnosperms did not have. Giant dinosaurs ate a lot, and a large number of angiosperms led to excessive accumulation of toxins in the body and finally poisoning.

Acid rain said: There may have been a strong acid rain at the end of Cretaceous, which dissolved trace elements including strontium in the soil. Dinosaurs ingested strontium directly or indirectly through drinking water and food, which led to acute or chronic poisoning and eventually died in batches.

Disease theory: authoritative pathologists in the United States believe that when the dinosaur species reached its peak, a mysterious virus or plague similar to AIDS faced by human beings suddenly swept the whole earth, making the species that dominated the earth for 65.438+0.4 billion years extinct.