New evidence discovers the secret Denisovans

News – An international group of researchers led by the University of Adelaide has carried out a comprehensive genetic study and found no evidence that there is an interrelationship between modern humans and older people known from fossil records. the Island of Southeast Asia. They found further DNA evidence of our secret old cousins, the Denisovans, which may have led to large-scale discoveries in the area.

In the study published in Ecology Nature and evolution, the researchers studied the genomes of more than 400 modern humans to study the interfaith events between humans and modern humans that reached Southeast Asia 50,000-60,000 years ago .

In particular, they focused on finding signatures that reflect interfaith from species that are very different from the area’s fossil record.

One of the richest fossil records in the region (from at least 1.6 million years ago) records human evolution in the world. There are currently three notable older people identified from the fossil record in the area: Homo erectus, Homo floresiensis (known as Island Flores hobbits) and Homo luzonensis.

These species are known to have lived to be around 50,000-60,000 years ago Homo floresiensis and Homo luzonensis, and about 108,000 years for Homo erectus, which means they may have gotten over how modern human populations came to be.

The results of the study showed no evidence of interfaith. Nonetheless, the team was able to confirm previous results showing high levels of Denisovan ancestry in the area.

Lead author and ARC Research Partner from the University of Adelaide Dr João Teixeira said: “Compared to our other cousins ​​the Neanderthals, which have an extensive fossil record in Europe, the Denisovans are known almost directly from the record DNA. The only physical evidence is that Denisovan has been a finger bone and some other fragments found in a cave in Siberia and, more recently, a piece of jaws found in High Tibetan floor. ”

“We know from our own genetic records that the Denisovans mixed with modern humans who came out of Africa 50,000-60,000 years ago both in Asia, and how humans moved the today through Southeast Asian Island en route to Australia.

“Denisovan’s DNA levels in contemporary figures indicate that there has been a major interfaith in Southeast Asia.

“The mystery remains, why didn’t we find their fossils with the other old people in the area? Do we need to review the existing fossil record to consider other opportunities? ”

Co-author Chris Stringer from the Natural History Museum in London said:

“As he has known the fossils Homo erectus, Homo floresiensis and Homo luzonensis they may have seemed in the right place and time to represent the mysterious ‘southern Denisovans’, their ancestors in Southeast Asian Island seemed to be at least 700,000 years old. back. Which means that their lines are too old to represent the Denisovans who, from their DNA, were closer to the Neanderthals and modern humans. “

Co-author Professor Kris Helgen, Chief Scientist and Director of the Australian Museum Research Institute, said: “These analyzes provide an important window on human evolution in an area that is very interesting, and shows the need for more archaeological research in the area between mainland Asia and Australia. ”

Helgen said: “This research also highlights a pattern of ‘megafaunal’ survival that coincides with known ranges of humans living in this part of the world. Large animals living in the area today include the Komodo Dragon, the Babirusa (a pig with amazing tusks upside down), and the Tamaraw and Anoas (small wild buffalos).

“This suggests that exposure to the pressure of hunting with older people may have allowed the megafaunal species to survive in contact with modern humans. In areas where prehistoric humans have not met, such as Australia and New Guinea, terrestrial animals have become extinct more than humans over the past 50,000 years. ”

Dr Teixeira said: “The research confirms previous studies that the Denisovans were in the Island of South East Asia, and that modern humans did not interact with more diverse human groups in the region. This opens up two equally exciting opportunities: either a major discovery is on the way, or we need to reassess the current fossil record on the East Island. South Asia. ”

“Whichever way you choose to look at it, there are exciting times ahead in palaeoanthropology.”