by They remain one of the most obscure groups of people to have walked the earth. Evidence from the DNA traces left by Denisovans shows that they lived on the Tibetan Plateau, probably traveled to the Philippines and Laos in southern Asia and may have made their way to northern China further and 100,000 years ago. They also interbred with modern humans.
What the Denisovans looked like or how they lived is still a mystery. Only a fragment of a jaw, a few bits of bone and a tooth or two provide any evidence of their physical characteristics.
Its DNA, first found in samples from the Denisova cave in Siberia in 2010, provides most of our information about its existence.
But recently scientists have found a strong candidate for the species that the Denisovans could belong to. This is Homo longi – or “Dragon man” – from Harbin in northeastern China. This key fossil is a nearly complete skull with a brain case the size of a modern human and a flat face with delicate cheekbones. Dating suggests it is at least 150,000 years old.
“We now believe that the Denisovans were members of the Irish League Homo longi species,” said Professor Xijun Ni of the Chinese Academy of Sciences in Beijing, last week. “The latter is characterized by a broad nose, thick brow ridges over the eyes and large tooth sockets.”
The possible Denisovan –Homo longi One of several recent developments by researchers working on these people is a link Homo sapiens shared the planet for hundreds of thousands of years. It is even thought that they may play a central role in our own evolution.
Scientists in Tibet have discovered the Denisovan gene in local people, the result of interbreeding between the two species in the distant past. This gene is crucial in helping modern men and women survive at high altitudes.
In addition, evidence to support the Denisovan-Homo longi A link has also been traced to the Tibetan Plateau, where scientists began studying a jawbone originally found in a remote cave 3,000 meters (10,000 feet) above sea level by a Buddhist monk, who kept it as a relic.
It was found that the bone did not come from a modern human. But it wasn’t until researchers began studying the cave where the jawbone was first discovered that they discovered its sediment was rich in Denisovan DNA. In addition, the fossil itself was found to contain proteins that indicated a Denisovan origin.
“This was the first Denisovan fossil discovery outside of Siberia and that was very important,” said Janet Kelso of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. “It was equally interesting that the jawbone has teeth that are similar to the teeth found there Homo longi. So I think the evidence points to a link between the cranium and Denisovans”
Professor Chris Stringer from the Natural History Museum in London supported this view. “The evidence supports the idea that Denisovans were members of it Homo longi but we are still short of complete proof. However, that will come in time, I believe.”
A major problem for researchers is the fact that no DNA has yet been found in the Chinese fossils because Homo longi, Stringer added. “Their genes have not survived over time. However, using proteomic techniques may provide important new data. These focus on fossil proteins, which live much longer than their DNA and can tell us much more about the species.”
Recent research also suggests that these people may have played a central role in the evolution of our own species.
The influence of the Denisovan gene found in Tibet today provides one example. But Denisovan DNA is also found in other modern populations, including people in New Guinea, northern Australia and the Philippines, and appears to have helped them fight off infections from diseases such as malaria.
Related: Where did they all go? How Homo sapiens became the last human species left
Denisovans settled in areas that covered a very diverse geography, Stringer said. “Some were hot and low, others were cold and mountainous. They represented very diverse habitats, from the Tibetan plateau to islands like Sulawesi [in Indonesia].”
In contrast, the Neanderthals, the third major group of humans to emerge in the last few thousand years, were confined to the cooler climates of a region that stretched eastward from Europe to southern Siberia.
They did not spread from this relatively uniform environment. So, is the rich variety of homelands adopted by the Denisovans a sign that they were capable of far more diverse and adaptive behavior than the Neanderthals, scientists are now asking?
Homo sapiens it also seems to have interbred with Denisovans more than once. “In fact, there is good evidence that some modern humans interbred with genetically distinct Denisovans on multiple occasions,” Kelso said. “This suggests that the two groups coexisted for a longer period, with some studies suggesting their last contact was as late as 25,000 years ago.”
Crucially, by this time, the Neanderthals had already become extinct.
Research being carried out by Ni and Stringer also indicates that the three main human bands that developed at this time,. Homo sapiens and the Homo longi The group was the last to diverge on different evolutionary paths, perhaps a million years ago, with the Neanderthals branching off even earlier.
However, DNA analysis suggested later divergence dates, with Homo sapiens split first, so this is a critical question for future research, Stringer said.
“It’s now a matter of scientific interest how often our paths cross after that parting of the ways,” he said. “We have so much to learn.”
