Some of the last surviving Neanderthals were remarkably diverse ‪-‬ suggesting inbreeding didn't doom them

Key Points:

• A new study analyzing DNA from 27 Neanderthals, including a high-quality genome, reveals that some late Neanderthals exhibited greater genetic diversity than previously believed, challenging the idea that genetic decline due to inbreeding was the main cause of their extinction.
• The research focused on Neanderthals from northwestern Europe, particularly Belgium and France, showing these groups were genetically interconnected and less inbred compared to isolated Siberian Neanderthal populations.
• Findings indicate that late Neanderthals in this region formed at least four distinct genetic groups, with population splits likely tied to warmer climatic periods that favored expansion.
• Despite coexisting with modern humans in Europe for thousands of years, these Neanderthals showed no evidence of recent interbreeding with Homo sapiens, highlighting an asymmetry where modern humans carry Neanderthal DNA but not vice versa.
• Researchers suggest social factors may have limited Neanderthal-modern human gene flow in this direction, and future studies aim to explore genetic diversity in Neanderthals from other regions, though DNA preservation challenges remain.