That "Ole gray mare" in the pasture was likely highly selected for during the domestication of horses and, according to some researchers, resembles her forefathers little in terms of coat coloring.

While many wild animal species are colored relatively uniformly, our domestic horse stock show "a broad variety of coat color patterns," wrote animal geneticists Stefan Rieder from the Swiss College of Agriculture in Zollikofen, Switzerland, in a recently published review article on the history and commercial applicability of the genes responsible for coat colors in horses.

One theory explaining this "horse of a different color" phenomenon is that, historically, only a few coat colors might have been appropriate for survival in the wild. For example, horses of a certain color could have been better camouflaged, considered a more appropriate mate, have more tolerance to certain pathogens, or better adapt to the environment than horses of other colors.

During domestication, however, human preferences resulted in the selection of horses with selected colors, resulting in horses with stunning and sometimes elaborate patterns