The ancient humans known as the Denisovans hunted a wide variety of animals on the Tibetan Plateau, including blue sheep, yaks, and snow leopards. This diverse diet allowed them to thrive at high altitudes tens of thousands of years before the arrival of modern humans.

“The Denisovans were very behaviorally flexible,” Fried Welcker “They're really able to adapt to their local environment and the species that live there,” say researchers from the University of Copenhagen in Denmark.

The Denisovans are one of the most mysterious groups of humans that ever lived on Earth. They were first described in 2010 based on DNA extracted from a finger bone fragment found in the Denisova Cave in the Altai Mountains of Russia. This was the first time a group of humans had been identified based solely on DNA.

Denisovans were likely once widespread in South Asia because many people in South and Southeast Asia today carry Denisovan DNA. The Denisovans were highly adaptive, inhabiting various regions from Siberia to Southeast Asia. However, very little is known about their physical characteristics due to the scarcity of remains.

In 2019, Welcker and other researchers described a 160,000-year-old jawbone found in the Baishiya karst caves of Xiahe, on the northeastern Tibetan Plateau. Proteins extracted from one of the teeth were identified as Denisovan.

The following year, another group Denisovan DNA in cave sedimentsThe DNA could have been dated to 100,000, 60,000 or even 45,000 years ago, suggesting the Denisovans lived there for more than 100,000 years.

The Tibetan Plateau is 4,000 meters above sea level. The air is thin, cold, and dry – a tough place to live. To understand how the Denisovans managed to survive for so long, Welcker and his colleagues studied animal bones from the Baishiqiao cave. By observing the bones' shapes and extracting characteristic proteins, they were able to identify 2,005 of the 2,567 bones or bone fragments found.

The most numerous were blue sheep (Pseudo Nayaur) Among them were sheep and goats, Welcker said. Other medium-sized herbivores included wild yaks, Tibetan gazelles, and red deer. There were also small animals with grooved teeth, such as flying squirrels and porcupines. Plus larger carnivores, such as spotted hyenas, wolves, and snow leopards, as well as birds, such as golden eagles.

Most of the bones appear to have been brought there by Denisovans – 19 percent bear clear evidence, such as cuts made by stone tools – while less than 1 percent bear tooth marks or other signs indicating they were brought there by rodents or carnivores.

“This is the second site where we can be absolutely certain that Denisovans were present and that the associated assemblages concretely represent their behavior.” Samantha Brown At the University of Tübingen, Germany.

Stone tools but no human remains have been found at other sites on the Tibetan plateau, so it's unclear who lived there. Further afield, a single molar found in 2022 at Tam Ngu Hao 2 limestone cave in Laos may point to a mysterious human presence. Tentatively identified as Denisovan.

Brown says it's not possible to draw many inferences about Denisovan capabilities from so few remains, “but we expect that Denisovans were once found as far north as Siberia, and possibly as far south.” [the islands of] Southeast Asia. As more of their remains are discovered, we may really begin to understand that the Denisovans were highly adaptive.”

One of the bones found in the White Cliff Cave, a rib fragment, turned out to belong to another Denisovan. It was found in sediments dating back 48,000 to 32,000 years ago, making it the youngest Denisovan specimen known to date. Stone tools found at Nuwia Devou on the plateau This provides evidence that modern humans were living there by 40,000 years ago, suggesting that Denisovans and modern humans coexisted in the region.