DNA Reveals Unexpected Origin of Enigmatic Mummies in China

They recreate the faces of three mummies over 2,000 years old 0:58

(CNN) -

Since their discovery, the antiquity of hundreds of mummies buried in boats in an inhospitable desert region of northwest China has puzzled and divided archaeologists.

Found in the Tarim Basin in Xinjiang mainly in the 1990s, the bodies and clothing of the mummies are surprisingly intact despite being up to 4,000 years old.

Preserved naturally by the dry desert air, his facial features and hair color can be clearly seen.

Their western appearance, woven and felt woolen garments, and the cheese, wheat, and millet found in their unusual graves suggested that they were shepherds from the western Asian steppe or migrant farmers from the mountains and desert oases of central Asia.

Hundreds of mummified bodies have been found throughout the Tarim Basin in Xinjiang in northwest China, dating back about 4,000 years.

This is an aerial view of a site called Xiaohe Cemetery.

However, a new study by Chinese, European and American researchers that analyzed the DNA of these 13 mummies, sequencing their genomes for the first time, has painted a different picture.

Their analysis suggests that the remains did not belong to newcomers, but to a local group descended from an ancient Asian Ice Age population.

"Mummies have long fascinated scientists and the public since their original discovery. In addition to being remarkably preserved, they were found in a very unusual context and exhibit diverse and distant cultural elements," said Christina Warinner, associate professor of anthropology at Harvard University.

"We found strong evidence that they actually represent a highly genetically isolated local population," added Warinner, who is also a leader of the microbiome sciences group at the Max Planck Institute for Evolutionary Anthropology and author of the study that was published in the journal Nature. on Wednesday.

advertising

"However, in contrast to their genetic isolation, they seem to have openly adopted new ideas and technologies from their neighboring pastoralists and farmers, while developing unique cultural elements not shared by other groups," he said.

• READ:

  At least 34 mummies found in a thousand-year-old tomb in Egypt

The researchers analyzed genetic information from the oldest mummies in the Tarim Basin, dating back 3,700 to 4,100 years, along with sequenced genomes from the remains of five people from the northernmost Dzungarian Basin in the Xinjiang Uyghur Autonomous Region in China.

They date back between 4,800 and 5,000 years and are the oldest human remains found in the region.

Incredible crossroads

Ancient DNA can provide powerful evidence about people's movements at a time when written records or other clues are scarce, said Vagheesh Narasimhan, an assistant professor at the University of Texas at Austin who has worked on genetic samples from the Central Asian region.

He was not involved in the study and called the research "exciting."

The research found that the Tarim Basin mummies showed no signs of mixing (a scientific term for having babies) with other groups living at the same time.

The mummies were direct descendants of a group that was once widespread during the Ice Age, but had largely disappeared by the end of that era, some 10,000 years ago.

Known as ancient North Eurasians, remnants of this hunter-gatherer population survive only fractionally in the genomes of current populations, and the indigenous peoples of Siberia and America have the highest known proportions.

Finding them in the Tarim basin and dated to these years was unexpected.

A naturally mummified Bronze Age woman, who was buried at Xiaohe in the Tarim basin.

The other genetic samples from the far north of Xinjiang showed that the people they came from mixed extensively with different Bronze Age populations in the region, making it remarkable that the mummies from the Tarim Basin were so genetically isolated. .

Although now remote, in the Bronze Age "this was a region of incredible crossroads. There was a vibrant mix of North, South, East and West dating back 5,000 years," said Michael Frachetti, professor of anthropology at Washington University. in Saint Louis, who was not involved in the study.

"It makes it even more paradoxical in a way that you have a community that is strongly integrated from cultural perspectives, but that maintains some very, very iconic and unique components of its own local ideology, local culture, local burial traditions as well as a seemingly genetic profile. unmixed that goes back even further to primordial ancestry in deep times. "

Narasimhan said it was possible for a population to be genetically isolated but also culturally cosmopolitan.

"It is not necessary that genetics always go hand in hand with cultural or linguistic exchange," he said.

"People can always adopt new techniques, be it agricultural or metallurgical from other groups, or change their funeral practices, etc., without population movement or replacement."

Unanswered questions about mummies

While DNA study reveals tantalizing details about the mummies, it is unlikely to be the last word on their origins.

The study looks at mummies found at a single site, and it is unclear whether sequencing a wider range of sites in the Tarim Basin could result in the discovery of different genetic links, Narasimhan said.

Frachetti said that ancient genetic samples from this region are still relatively rare, and it is possible that they could find other genetic influences from the Himalayas or Tibet.

Although previous work has shown that the mummies lived on the shores of an oasis in the desert, it is not yet clear why they were buried in boats covered in cattle skins with paddles on their heads, a rare practice not seen elsewhere. of the region and perhaps best associated with the Vikings.

"They bury their bodies in boats, and no one else does that. That means that the origin of that tradition remains one of the greatest enigmas of this desert population, which should be the last community in the world to do this," said Farchetti .

Mummies