Denisovan human bones found at high altitude in Tibet

3 Jul. () –

Bone remains found in a Tibetan cave at 3,280 m above sea level indicate that an ancient group of humans survived there for many millenniaaccording to a study published in Nature.

Denisovans are an extinct species of ancient humans. who lived at the same time and in the same places as Neanderthals and Homo sapiens. Archaeologists have only discovered a handful of Denisovan remains. Little is known about the group, including when it became extinct, but there is evidence to suggest that they interbred with Neanderthals and Homo sapiens.

A research team led by Lanzhou University, China, the University of Copenhagen, Denmark, the Tibetan Plateau Research Institute, and involving the University of Reading studied more than 2,500 bones from the Baishiya karst cave on the high-altitude Tibetan Plateau, one of only two places where Denisovans are known to have lived.

Their new analysis has identified a new Denisovan fossil and shed light on the species’ ability to survive fluctuating climatic conditions, including the Ice Age, on the Tibetan Plateau between 200,000 and 40,000 years ago.

Dr Geoff Smith, a zooarchaeologist at the University of Reading, is a co-author of the study. He said: “We were able to identify that Denisovans hunted, butchered and ate a variety of animal species. Our study reveals new information about Denisovan behaviour and adaptation to both high altitude conditions and climate changes. We are just beginning to understand the behavior of this extraordinary human species.“.

The skeletal remains from the Baishya karst cave were broken into numerous fragments, preventing their identification. The team used a new scientific method that exploits differences in bone collagen between animals to determine which species the skeletal remains came from.

Dr Huan Xia from Lanzhou University said: “Zooarchaeology by mass spectrometry (ZooMS) allows us to extract valuable information from bone fragments that are often overlooked, which provides deeper insight into human activities.”

The research team determined that most of the bones were from blue sheep, known as bharal, as well as wild yaks, equines, the extinct woolly rhinoceros and the spotted hyena. The researchers also identified bone fragments of small mammals, such as marmots and birds.

Dr Jian Wang, from Lanzhou University, said: “Current evidence suggests that it was Denisovans, not any other human group, who occupied the cave and made efficient use of all the animal resources available to them during their occupation.”

Detailed analysis of the fragmented bone surfaces shows that the Denisovans extracted meat and bone marrow from the bones, but it also indicates that humans used them as raw material to produce tools.

The scientists also identified a rib as belonging to a new Denisovan individual. The layer where the rib was found dates back between 48,000 and 32,000 years, which implies that this Denisovan individual lived at a time when modern humans were dispersing across the Eurasian continent. The results indicate that Denisovans lived during two cold periods, but also during a warmer interglacial period between the middle and late Pleistocene eras.

Dr Frido Welker, from the University of Copenhagen, said: “Taken together, the fossil and molecular evidence indicates that the Ganjia Basin, where the Baishiya Karst Cave is located, provided a relatively stable environment for the Denisovans, despite its high altitude.

“Now the question arises as to when and “why did these Denisovans of the Tibetan Plateau become extinct?”