Nov 21, 2014 10:52 AM EST By Russell Westerholm, UniversityHerald Reporter

Ancient Tibetans settled in their homes in the high altitudes of "the roof of the world," they apparently relied on barley, a frost-resistant crop.

According to the Washington Post, authors of a study published in the journal Science found evidence of a human presence on the Tibetan Plateau from about 20,000 years ago. But the ancient Tibetans did not start settling down until nearly 15,000 years later, at which point they moved up past the altitude of 8,200 feet above sea level.

"Until now, when and how humans started to live and farm at such extraordinary heights has remained an open question. Our understanding of sustained habitation above 2-3,000m on the Tibetan Plateau has to date been hampered by the scarcity of archaeological data available," study lead author Martin Jones, an archaeology professor at the University of Cambridge, said in a press release. "But our findings show that not only did these farmer-herders conquer unheard of heights in terms of raising livestock and growing crops like barley and millet, but that human expansion into the higher, colder altitudes took place as the continental temperatures were becoming colder.

"Year-round survival at these altitudes must have led to some very challenging conditions indeed - and this poses further, interesting questions for researchers about the adaptation of humans, livestock and crops to life at such dizzying heights."

Barley is still an important crop for modern Tibetans, as they learned early on that millet would not withstand the frost that was common at the altitudes they were settling in.

"Although you can't exactly argue that the lowlands were so full there was no space, you can argue that society was changing and breaking off into different kinds of communities," Jones told the Post. "They were differentiating themselves. The ownership of land and resources was key."

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