The story appears on

Page A8

December 15, 2009

GET this page in PDF

Free for subscribers

View shopping cart

Related News

Home » Nation

Genes place Paleolithic-era humans on high Tibet plateau

Chinese scientists have found through genetic studies that human beings successfully colonized the Qinghai-Tibet Plateau in the Late Paleolithic Age, at least 21,000 years ago.

The plateau, with an average altitude above 4,000 meters and known as "the Roof of the World," is one of the most challenging areas in the world for human settlement because of its environmental extremes, such as severe cold and low oxygen levels.

"Through Paleolithic-era stone tools excavated from the plateau years ago, archaeologists believed human beings possibly inhabited the plateau 30,000 years ago," said Zhao Mian, a researcher from the Kunming Institute of Zoology with the Chinese Academy of Sciences.

But with the drastic drop of temperature on Earth in the Last Glacial Maximum of the Late Paleolithic Age, about 23,000 years ago, many species could not adapt to the changes and died out, the researcher said.

"Scientists have been debating heatedly whether human beings on the plateau had survived the adverse conditions," Zhao said.

Geneticists attempted to find out when human beings settled on the plateau by determining the age of the ancient components found in the genes of modern-day Tibetans.

"But due to few DNA samples of Tibetans, especially from Tibet, and lack of distinguishability in previous studies, geneticists found it hard to judge whether Tibetans have ancient components in their genes," she said.

Led by her tutor Zhang Yaping, director of the Kunming Institute of Zoology, Zhao and 14 other geneticists, including a German scientist, set up a research group three years ago.

They collected 680 genome samples of genetic structure from Tibetans in several major Tibetan-populated areas, including Tibet and Qinghai, Gansu, Sichuan and Yunnan provinces. Of those, 388 were sampled from Tibet.

"Based on studies of their mitochondrial DNA genome variation, our results confirm the vast majority of Tibetan matrilineal components can trace their ancestry to ... what is now northern China, or about 10,000 years ago, which accords with previous studies," Zhao said.




 

Copyright © 1999- Shanghai Daily. All rights reserved.Preferably viewed with Internet Explorer 8 or newer browsers.

沪公网安备 31010602000204号

Email this to your friend