XINJIANG, China: The ancestry of hundreds of mummified bodies buried in boats in an inhospitable desert region of northwest China has puzzled and divided archaeologists since their discovery.

In the 1990s, in the Tarim Basin in Xinjiang, the mummies and their clothing were discovered intact and preserved by the dry desert air, despite being up to 4,000 years old.

Their facial features and hair color, which look western, are still clearly visible, and their felted and woven wool clothing, as well as cheese, wheat and millet found in their unusual graves indicated they were long-distance herders from the West Asia steppe or migrating farmers from the mountains and desert of Central Asia.

But a new study by Chinese, European and American researchers who analyzed the DNA of 13 mummies suggested they were not newcomers but a local group descended from an ancient ice age Asian population.

An author of the study, which was published in the journal Nature on Wednesday, Christina Warinner of Harvard University, said, "The mummies have long fascinated scientists and the public alike since their original discovery. Beyond being extraordinarily preserved, they were found in a highly unusual context, and they exhibit diverse and far-flung cultural elements."

"We found strong evidence that they actually represent a highly genetically isolated local population. But in contrast to their genetic isolation, they seem to have openly embraced new ideas and technologies from their herder and farmer neighbors, while also developing unique cultural elements shared by no other groups," she added.

The study analyzed the genetic information of the oldest Tarim Basin mummies, which are 3,700 to 4,100 years old, as well as from the remains of five people from the Dzungarian Basin farther north in the Xinjiang Uyghur Autonomous Region, which are the oldest human remains found in the region, dating back between 4,800 and 5,000 years ago.

The results of the research showed the Tarim Basin mummies showed no sign of admixture, a scientific term for having children, with other contemporary ethnic groups and were direct descendants of a group that was once widespread during the ice age.

Meanwhile, the other group that came from farther North in Xinjiang were found to have mixed extensively with different Bronze Age populations in the region.

Although the region is remote now, in the Bronze Age "this was a region of incredible crossroads. There was vibrant mixing of North, South, East and West going back as far back as 5,000 years," said Michael Frachetti, professor of anthropology at Washington University in Saint Louis.