Neanderthal-Human Interbreeding Lasted 7,000 Years, Starting 47,000 Years Ago

Dec 12, 2024, 07:02 PM

A comprehensive study involving the analysis of ancient and modern human genomes has provided new insights into the interbreeding between Homo sapiens and Neanderthals. Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of California, Berkeley, examined around 300 genomes, including 59 ancient individuals who lived between 2,000 and 45,000 years ago. The study suggests that this interbreeding occurred over a significant period, starting around 50,500 years ago and lasting for about 7,000 years, until the Neanderthals began to disappear. This timeline aligns with archaeological evidence indicating that modern humans and Neanderthals coexisted in Eurasia for several thousand years. The analysis also revealed that Neanderthal gene flow into modern humans was likely a single, shared event around 47,000 years ago, with some Neanderthal genes possibly conferring survival advantages related to immune function, skin pigmentation, and metabolism. However, regions of the genome devoid of Neanderthal DNA, known as 'Neanderthal deserts,' suggest that some Neanderthal gene variants were harmful to modern humans and were rapidly selected against. The study further indicates that the initial migration of modern humans from Africa was largely completed by 43,500 years ago. The oldest modern human genomes, from individuals in Zlatý kůň, Czechia, and Ranis, Germany, show they belonged to a small, isolated group that had recently mixed with Neanderthals but left no present-day descendants. These individuals were part of the Lincombian-Ranisian-Jerzmanowician (LRJ) culture, with Neanderthal DNA contributing between 1% and 2% to modern non-African genomes.