We may be hybrids of two different human species.

(NLDO) - Scientists from Cambridge University (UK) have found new evidence about the origin of Homo sapiens..

For the past two decades, the prevailing view in evolutionary genetics has been that we, Homo sapiens — also known as “modern humans” — first emerged in Africa about 300,000 years ago and descended from a single lineage.

However, that notion may be overturned after new DNA analysis.

We Homo sapiens may carry the blood of many different ancient human species - Illustration AI: Thu Anh

Publishing the results in the scientific journal Nature Genetics , the authors said Homo sapiens is the result of hybridization between two populations, most likely Homo heidelbergensis and Homo erectus, in an 80:20 ratio.

These are two extinct species of the genus Homo (Human), which once included many species but now has only one species remaining, Homo sapiens.

Homo heidelbergensis is thought to be the primary ancestor of Homo neanderthalensis (Neanderthal), another sibling species in the genus Homo that interbred with our species, leaving behind about 2% of the DNA in modern humans.

They were not very developed so the fossil evidence left behind is very modest.

Homo erectus, nicknamed "upright man", is older and is considered the first species to truly "escape" the hominid fate. They walked upright like us and knew how to use and produce tools.

This species has been present on earth for about 2 million years.

In this new study, the authors developed an algorithm called cobraa to simulate how ancient human populations split and then merged together.

They tested the algorithm using simulated data and applied it to real human genetic data from the 1000 Genomes Project, which includes DNA sequences from multiple populations across Africa, Asia, Europe, and the Americas.

The results confirmed that the two ancestral populations Homo heidelbergensis and Homo erectus split from a common lineage.

But soon after the split, a severe bottleneck appeared in one of the two populations, suggesting that the lineage shrank to a very small size before expanding slowly over a period of 1 million years.

This population later contributed about 80% of the genetic material of modern humans and appears to have also contributed the majority of the DNA to Homo neanderthalensis.

The above data are consistent with known evidence for Homo heidelbergensis.

300,000 years ago, this population faced a major genetic introgression, that is, interbreeding with other species.

Interspecies DNA entered this ancestral lineage at 10 times the rate that Homo neanderthalensis DNA entered Homo sapiens 50,000 years ago. That other human species was Homo erectus. And the result of that powerful mixing was the birth of our species.

"This tells us that our history is much richer and more complex than we imagined," Professor Aylwyn Scally, a member of the research team, commented to Sci-News.

Source: https://nld.com.vn/chung-ta-co-the-la-con-lai-cua-2-loai-nguoi-khac-nhau-196250320093542822.htm