A extinct breed of horses was populating North America during the last ice age, a new DNA test of fossilized bones found in Wyoming, Nevada and the Yukon reveals.
Prior to this work, which included US and Canadian teams, the researchers thought that these thin-skinned, light-frame horses were related to the Asian wild ass or evening primrose, or simply to a species distinct from the genus Equus , which includes live horses, donkeys and zebras.
These new results published in the eLife journal tend to show that these horses were not closely related to a current species.
The remains had been found in natural caves, caves and gold fields.
The newly identified species received the name Haringtonhippus francisci .
His name was given in honor of paleontologist Richard Harington of the Canadian Museum of Nature in Ottawa. This scientist has devoted his career to studying the fauna of the last ice age. It is he who brought to light the first fossils of this species in the early 1970s.
The species diverged from the main trunk of the family tree of the genus Equus there are about 5 million years.
The long evolutionary distance between these missing horses and all current horses has surprised us, but it has given us a rare opportunity to name a new breed of horse.
The Haringtonhippus francisci was a widespread species. It populated much of North America, living alongside Equus populations , but never breeding with them. In the Canadian north, Haringtonhippuss survived until about 17,000 years ago.
At the end of the last ice age, both groups of horses disappeared from the continent, along with other large animals such as woolly mammoths and saber-toothed tigers.
Although Equus survived in Eurasia after the last ice age, eventually leading to domestic horses, the Haringtonhippus found itself in an evolutionary dead end.