Due to the ground's resistance, you cannot run as fast as you can fly from a physics perspective. Because of this, many of the fastest animals are birds.

Technically, the peregrine falcon is the fastest, but because of its shape and gravity, its movement cannot be considered to be "flying."... Read other most fastest animals in the world in details...https://bestnewsnet.com/top-12-fastest-animals-in-the-world/