Historical data of dinosaurs

Dinosaurs are a kind of reptiles that appeared in Mesozoic. The vigorous limbs, long tail and huge body are the portrayal of most dinosaurs. They mainly inhabit the open areas of woodland or lakeshore plain.

The sudden disappearance of dinosaurs at the end of Cretaceous 65 million years ago became a mystery in the evolutionary history of life on earth. This mystery has not been solved so far. In the past, all living things on the earth were recorded in fossils.

Many dinosaur fossils have been found in Mesozoic strata. A large number of bones or various shapes can be seen in it. However, in the Cenozoic strata below.

But we can't see the fossils of non-bird dinosaurs at all, so we infer that non-bird dinosaurs died out together in Mesozoic, and now only birds are left. Most scientists agree that birds belong to dinosaurs.

There are many kinds of dinosaurs, and their shapes and habits are very different. The largest fragile double-chambered dragon may be more than 50 meters, while the smallest hummingbird may be less than 10 cm. As far as eating habits are concerned, there are docile herbivores and fierce carnivores, as well as omnivorous dinosaurs who are both vegetarian and vegetarian.

Extended data:

A new study found that a catastrophic asteroid impact may not only directly lead to the extinction of dinosaurs on earth, but also trigger a large-scale eruption of volcanoes in the depths of the ocean.

If the timing of the asteroid's impact on the earth is not accidental, this event has become another way for external celestial bodies to have a significant impact on life on the earth. In this process, the submarine volcanic eruption caused by the impact destroyed more than 70% of life on earth.

About 66 million years ago, an asteroid at least 9.6 kilometers wide hit the earth, especially in Mexico's Yucatan Peninsula. The impact event triggered a global earthquake.

2065438+On February 7th, 2008, a research report was published in the journal Science Progress. The report said that the impact was extremely powerful, which not only triggered a global earthquake, but also caused the magma ejected from the submarine volcano to be more violent.

The eruption of submarine volcano further aggravated the disastrous consequences of asteroid impact, triggered a large-scale wildfire, led to the global temperature drop, and a large-scale acid rain appeared on the earth.

These events * * * led to the extinction of life on the earth, about three-quarters of the creatures, including dinosaurs.

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