Traces of 'mysterious ancestor' discovered that contributed 20% of modern humans' DNA

In new research, scientists have uncovered unexpected traces of a mysterious ancestral population that provided 20% of modern humans' genes, and may have made us smarter.

Neanderthals also contributed genes to modern humans.

Scientists have long believed that modern humans descended from a single ancestral lineage. However, new research not only challenges this view, but also raises new mysteries about human evolution.

The split 1.5 million years ago

Based on a complete gene sequencing model, a team of scientists from Cambridge University (UK) discovered that modern humans originated from two distinct populations that separated about 1.5 million years ago.

About 300,000 years ago, these two populations fused again and created the ancestors of modern humans. The recombination allowed one population, also the ancestors of Neanderthals and Denisovans, to contribute 80 percent of modern humans’ genetic makeup, and a second, previously unknown population to contribute the remaining 20 percent, according to the report published in the journal Nature Genetics .

“The question of human origins has been a constant pursuit for centuries,” said report author Dr Trevor Cousins of the University of Cambridge. And new genetic evidence has revealed a complex history of human evolution.

Co-author Professor Richard Durbin noted that the new report shows that human origins were shaped by extensive evolutionary interactions rather than from a single population.

Why are humans small but have bigger brains than gorillas and chimpanzees?

Data from the 1,000 Genomes Project

To reach this conclusion, the Cambridge University research team analyzed data from the 1,000 Genomes Project, which includes genetic samples from populations around the world .

The approach allowed them to infer the presence of ancestral populations that did not leave direct evidence through fossils.

Unlike Neanderthal DNA, which now makes up about 2 percent of the modern human genome outside Africa, a previously unknown ancient population contributed up to 20 percent of the genes.

Some of the genes from the mysterious human are linked to brain function and neural processing, so likely played an important role in human evolution, according to Dr Cousins.

Source: https://thanhnien.vn/phat-hien-dau-vet-to-tien-bi-an-gop-20-adn-cho-nguoi-hien-dai-185250320095133801.htm