In 1959, the U.S. government advised hunters that they were permitted to kill a Yeti only in self-defense. The decree was prompted by findings from earlier expeditions—huge footprints, hides, and bones from a large, unidentified creature native to the Himalayas—which explorers thought could be from the mythical hominid that local Sherpas called the Yeti, or "wild man."

But now, researchers at the State University of New York in Buffalo and their colleagues have concluded that folklore about abominable snowmen in the Himalayas was just that. After testing evidence collected from the Tibetan Plateau and from museum collections, they found the biological root of the Yeti legends to be local bears.

In the new study, published in the Proceedings of the Royal Society B, researchers analyzed 24 hair, bone, tooth, skin, and scat samples. Nine of the samples were purported to be from Yetis, while the rest were gathered recently from the Tibetan brown bear, Himalayan brown bear, and Himalayan black bear. The team assembled complete mitochondrial genomes for the Himalayan brown bear and black bear for the first time, then analyzed and compared all of the samples. Of the nine allegedly from Yetis, eight were actually from Asian bears. One was from a dog.

While these particular findings suggest that the Yeti stories probably emerged from humans' encounters with bears, the study provides valuable genetic data that could shed light on how the bears evolved. The mitochondrial genomes—which are based on the genetic information passed down only through females—could reveal when the rare subspecies and more common bear species last shared a maternal ancestor, and how genetically dissimilar they are today, Science notes.

The genomic analysis showed that Tibetan brown bears share a close ancestry with North American and Eurasian brown bears. But the Himalayan brown bears branched off from their common ancestral tree about 650,000 years ago, when glaciers expanded over the Tibetan Plateau—which may have separated those bears from the larger gene pool. Understanding how the subspecies evolved could illuminate the environmental history of the region, said Charlotte Lindqvist, an associate professor of biological sciences at SUNY Buffalo and the study's lead scientist, in a statement. The genetic data may assist conservation of these vulnerable and endangered animals.

Lindqvist said that their technique could also be a useful tool for exploring the roots of folklore about large cryptids—as well as real beasts.

"Our findings strongly suggest that the biological underpinnings of the Yeti legend can be found in local bears," she said. "Our study demonstrates that genetics should be able to unravel other, similar mysteries."