The people of Tibet’s Baishiya Cave hunted everything they could, from marmots to wolves.
For quite a long time, the only place with the remains of Denisovans was the Denisova Cave in Altai. True, there were very few bones left, but by 2010, biology had developed methods that made it possible to read DNA that remained in prehistoric fossils. DNA from some human bones in the Denisova Cave showed that they did not belong to either Homo sapiens or Neanderthals. Thus, a third species of man appeared in science – the Denisovan man.
Another place with Denisovans appeared on the map relatively recently – Baishiya Cave on the Tibetan Plateau. In 1980, a Buddhist monk found a piece of a human jaw. Various human and animal remains were often found here, so the find did not cause much surprise: the monk gave the bone to the local religious leader, who gave it to Lanzhou University. The piece of jaw from Baishiya Cave lay there for thirty years until experts finally got their hands on it. We wrote that the Denisovan origin of the jaw was determined first by the preserved proteins, and then by DNA.
Now excavations in the Tibetan cave have begun to be carried out in order to learn more about the Denisovans. DNA from the Baishian sedimentary rocks, aged from 100 to 45 thousand years, turned out to be extremely similar to DNA from the Denisova Cave, which added to the arguments in favor of the fact that it was the Denisovans who lived in Baishia. But in addition to DNA, the sedimentary rocks also contain many bones, mainly of animals. Employees of Lanzhou University and the University of Copenhagen published in Nature article about what these bones are. They analyzed more than two and a half thousand fossils, from which an entire zoo was formed: there were gazelles, horses, yaks, goats, marmots, wolves, foxes, hyenas, golden eagles. They were identified not by DNA, but by preserved collagen proteins, in the amino acid sequence of which there are enough differences to distinguish one species from another.
The most important thing is that many of the bones showed traces of cuts and human impact in general. Most of these traces were found on the bones of herbivores, but they were also found on the bones of predators, including hyenas and golden eagles. The bones of marmots were broken in such a way as to extract the marrow. In Baishiya Cave, apparently, no other people lived except Denisovans (which distinguishes it from Denisova Cave, where traces of all three species can be found Homo). Therefore, we can assume with a high degree of certainty that the “traces of human influence” on animal bones were left by the Denisovans: they ate literally everything they could get. They must have been very skilled hunters, since they managed to kill both dangerous predators and nimble, fast rodents.
Among the many bones, the researchers came across a fragment of a human rib with protein residues. The fact that it belonged to a human was determined by collagen. However, collagen cannot be used to distinguish between Homo sapiens, Neanderthals and Denisovans, so they tried to check the amino acid sequences of two dozen other proteins that also remained on the rib. The protein residues turned out to be closest to the proteins of the Denisovans from Altai. In the future, they expect to extract DNA from the rib, because DNA will allow them to say much more accurately whether it was a Denisovan or not.
The rib itself was extracted from an archaeological layer aged 48-32 thousand years. It is known that the genome of modern humans contains Denisovan admixtures, and it is believed that between 48 and 32 thousand years ago, Denisovans interbred with A wise man in the eastern part of Asia. With the Denisovans from Baishia Cave we will better understand the evolution of humans, and obviously after new results they will be searched for here even more diligently.
Source: www.nkj.ru
