What would the world be like if dinosaurs were not extinct, Zhihu?

In short, if dinosaurs were not extinct, mammals would not be able to get enough niches, primates would not be able to evolve, and naturally there would be no human beings.

From a deeper perspective, the extinction of dinosaurs can actually be said to be an inevitable event. Generally speaking, dinosaurs were highly adaptable to the environment and could not bear any environmental changes. Even without the impact of meteorites, several prehistoric ice ages were enough to make them extinct. In the evolutionary history, mass extinctions are actually periodic, and a large number of species that are well adapted to the environment are extinct every time, leaving an niche for new species.