New DNA analysis shows late European Neanderthals were genetically diverse
A study of 27 additional Neanderthal genomes from northwestern Europe finds higher genetic diversity and limited inbreeding, challenging the view that genetic decline caused their extinction.
Scientists have added genetic data from 27 Neanderthal individuals uncovered at ten sites in present-day Belgium and France, including a new high-quality genome, to the existing record of four genomes. The analysis, published in Nature, indicates that late Neanderthals in northwestern Europe split from other known Neanderthals about 54,000 years ago and formed a large, interconnected population rather than isolated groups.
Unlike Siberian Neanderthals, which showed signs of frequent close-kin breeding, the newly examined individuals displayed little evidence of inbreeding and maintained a level of genetic diversity comparable to earlier Neanderthals. The researchers identified at least four distinct genetic sub-groups that likely emerged during warmer climatic periods, suggesting population expansions under favorable conditions.
The study also found no trace of recent modern-human DNA in the Belgian and French Neanderthals, despite their coexistence with Homo sapiens for up to 500 generations. This asymmetry contrasts with documented cases of early modern humans carrying recent Neanderthal ancestry.
"I am very happy to dispel the misconception that all Neandertals went extinct because they were too inbred," said Alba Bossoms Mesa, a doctoral researcher at the Max Planck Institute for Evolutionary Anthropology and lead author of the paper.
"Neanderthals lived across vast regions of Eurasia over hundreds of thousands of years, so of course there is a lot of variation between them," Mesa added.
"We have several examples of early modern humans who had a Neandertal ancestor only a few generations back. But in contrast, we do not yet have a single confirmed example of a Neanderthal individual with a recent modern human ancestor in their family tree," she said.
The findings suggest that reduced genetic diversity was not a universal driver of Neanderthal extinction and highlight the need for further DNA research from other regions, such as the Iberian and Italian peninsulas, where preservation conditions are more challenging.