Study challenges human-Neanderthal interbreeding theory
London: DNA similarities in modern human and Neanderthals could be the result of shared ancestry but not interbreeding, a new Cambridge study has claimed.
Researchers from the University of Cambridge found that similarities between the DNA or deoxyribonucleic acid of modern people and Neanderthals are more likely to have arisen from shared ancestry than interbreeding, a newspaper reported.
Previously, it had been suggested that interbreeding was common, explaining our shared genome.
Cambridge evolutionary biologists Dr Anders Eriksson and Dr Andrea Manica, found that the amount of DNA shared between modern Eurasian humans and Neanderthals - estimated at between 1-4 percent - actually comes from a common ancestor.
The pair used computer simulations to reassess the strength of evidence supporting hybridisation events.
They believe it can be explained if we both arose from a geographically isolated population, most likely in North Africa, which shared a common ancestor around 300-350 thousand years ago.
One group moved north to become ancestors of the Neanderthals, who emerged from an early migration from Africa into Eurasia.
The second group is believed to have moved south to become the ancestral population that gave rise to modern humans, Homo sapiens, which emerged from Africa about 70,000 years ago.
"To me the interbreeding question is not whether there was hybridisation but whether there was any hybridisation that affected the subsequent evolution of humans," Manica said.
"I think this is very, very unlikely. Our work shows clearly the patterns currently seen in the Neanderthal genome are not exceptional, and are in line with our expectations of what we would see without hybridisation," Manica was quoted as saying by the paper.
"So, if any hybridisation happened then it would have been minimal and much less than what people are claiming now," Manica added.
The study was published in PNAS journal.