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.
There are many kinds of dinosaurs, and their shapes and habits are quite different. Among them, the big one can be as big as dozens of elephants combined; Small, but almost like a chicken. 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.
There are different opinions about the reasons for their extinction. Some people think it's a planet, some people think it's orogeny, and some people think it's temperature change.