An early woolly rhinoceros from Tibet which used its horn as a snow shovel could rewrite theories about the evolution of giant Ice Age mammals.
The woolly rhino lived in the cold Himalayas 3.6 million years ago, before the start of the Pleistocene Ice Age.
Scientists suspect adapting to the harsh Tibetan climate may have helped the animal's descendants survive the big freeze to come.
The same could also be true for ancestors of other Ice Age "megafauna" such as the woolly mammoth, giant sloth and sabre-toothed cat, the experts believe. The research suggests that the Tibetan plateau may have been an "evolutionary cradle" for Ice Age giants.
Much has been written about the extinction of Ice Age mammals, but much less is known about their origins.
The new US research, reported in the journal Science, focused on the complete skull and lower jaw of a new species of woolly rhino, Coelodonta thibetana, discovered in the foothills of the Himalayas at a site called the Zanda Basin.
One special feature of the animal was a flattened horn, thought to be used to sweep away snow to reveal vegetation.
Lead author Dr Xiaoming Wang, from the Natural History Museum of Los Angeles, said: "Cold places such as Tibet, Arctic and Antarctic are where the most unexpected discoveries will be made in the future - these are the remaining frontiers that are still largely unexplored."
As well as the new woolly rhino, the team also found fossil remains of extinct species of three-toed horse, Tibetan bharal or "blue sheep", chiru or Tibetan antelope, snow leopard, badger and 23 other kinds of mammals.
Dr Richard Lane, from the US National Science Foundation, said: "This discovery clarifies the origin of the woolly rhinoceros - and perhaps much of the now extinct, cold-adapted, Pleistocene Eurasian megafauna - as the high-altitude environments of the Zanda Basin of the primordial Pliocene Himalayas."