Ancient DNA bucks tale of how the horse was tamed
Modern-day breeding, not domestication, winnowed genetic diversity
RIDE ON Mongolian horses (shown) and other present-day horse breeds have less genetic diversity than domesticated horses did around 2,000 years ago.
Eric Crubézy
DNA from 2,000-year-old stallions is helping rewrite the story of horse domestication.
Ancient domesticated horses had much more genetic diversity than their present-day descendants do, researchers report in the April 28 Science. In particular, these ancient horses had many more varieties of Y chromosomes and fewer harmful mutations than horses do now. Previous studies based on the genetics of modern horses concluded that domestication must have squeezed out much of the diversity seen in wild horses before the Ice Age. But the new findings suggest that the lack of diversity is a more recent development.
“Today, Y chromosomes of all horses are pretty much the same,” says evolutionary geneticist Ludovic Orlando of the Natural History Museum of Denmark in Copenhagen. As a result, scientists thought that ancient people started domesticating horses by breeding only a few
