Barley Helped Early Tibetans Survive at Extreme Heights
Early Tibetans might have to thank barley, a frost-resistant crop, for allowing them to survive at extreme heights, according to a new study.
Situated between 8,200 feet (2,500 meters) and 11,154 feet (3,400 meters) above sea level, there's a reason the Tibetan Plateau is called the "roof of the world." There's evidence that humans intermittently visited this place 20,000 years ago, but people didn't officially start calling it home until just 5,200 years ago. Until then, it seems, permanent homes trickled off at 8,200 feet above sea level.
However, early humans then started to set their sights higher.
"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 2-3,000 meters on the Tibetan Plateau has to date been hampered by the scarcity of archaeological data available," lead researcher Martin Jones, a professor of archaeology at the University of Cambridge, said in a press release.
Now Jones and his colleagues have determined through new findings that the presence of crops and livestock at these high altitudes allowed for more sustained human survival. The research group collected artefacts, animal bones and plant remains from 53 sites across the late Yangshao, Majiayao, Qiija, Xindian, Kayue and Nuomuhong cultures, all of which occupied the Tibetan Plateau.
Cereal grains like barley and millet were identified at all 53 sites as well as animal bones and teeth from sheep, cattle and pigs at 10 of the sites. (Scroll to read on...)
But as Tibetans moved higher up, The Washington Post reports, they gradually relied less on their traditional staple of millet and more so on barley. Barley was better able to resist the cold, frostbiting temperatures at the higher altitudes.
"What was really important was getting those core calories," Jones told The Post.
Lower oxygen levels at these dizzying heights also were an issue, but scientists such as study co-author Loukas Barton believe that early Tibetans acquired certain mutated genes tens of thousands of years ago that allowed them to adapt to this obstacle.
What's more, researchers found, was that these early humans conquered these unheard of heights at a time when continental temperatures were becoming even 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," Jones added in the release.
Their findings were published in the journal Science.