There are places in america and other parts of the world where herds of wild horses live, well-adapted to the environment. if mules are so much better adapted to harsh environments than either horses or donkeys, why have there never been populations of wild mules?

simple mules are a mix of hourse and donky and are born infertle they cant BREED.

a time line cause it goes from 685 to 978

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".