Scientists have generated genetic data from 27 Neanderthals who lived in Belgium and France less than approximately 52,500 years ago, painting a richer and more surprising portrait of how our closest hominin cousins organized their lives before their disappearance.
Reconstruction of a Neanderthal. Image credit: Neanderthal Museum.
Neanderthals lived in Europe and western Asia from at least around 430,000 years ago until around 40,000 years before present.
The high-quality nuclear genomes of four Neanderthals provided numerous insights into the diversity and population history of Neanderthals and their interactions with early modern humans.
The more recent Neanderthal from Croatia (45,000 years ago) showed higher genetic diversity and less evidence of recent inbreeding than do the older Neanderthals from Denisova and Chagyrskaya caves (120,000, approximately 110,000, and approximately 60,000 years ago) who lived in the easternmost part of the known Neanderthal range.
Further lower-coverage nuclear genomes from four late Neanderthals suggested close genetic affinities between individuals from geographically distant regions, such as Mezmaiskaya in Caucasus and Les Cottés in France, indicating possible long-range connectivity between late Neanderthals.
“Until now, we only had four high-quality Neanderthal genomes and a limited number of lower-quality ones, so most questions about the regional diversity of Neanderthals have been difficult to address,” said Alba Bossoms Mesa, a doctoral researcher at the Max Planck Institute for Evolutionary Anthropology.
“By generating genetic data from multiple individuals from the region of present-day Belgium and France, we can now examine late Neanderthal populations in much greater detail.”
In the new study, Bossoms Mesa and colleagues recovered genetic material from 26 Neanderthals from Belgium and France.
They also sequenced a high-quality genome from a 45,000-year-old Neanderthal individual found at Goyet Cave in Belgium, making it only the fifth such detailed Neanderthal genome ever produced.
Unlike Neanderthals previously studied from Siberia’s Altai region, who showed clear signs of mating among close relatives, the Belgian Neanderthals displayed no such genetic signatures.
The researchers also found that most of Neanderthals from Belgium and France were more closely related to one another than to contemporaneous Neanderthals elsewhere in Europe, pointing to a distinct regional population that nonetheless maintained broader connections across the continent.
“Our results show that the picture emerging from one region cannot simply be applied to all Neanderthals,” said Dr. Benjamin Peter, also from the Max Planck Institute for Evolutionary Anthropology.
“The late Neanderthals from northwestern Europe appear to have been part of a connected regional population, rather than small, isolated groups with frequent mating between close relatives.”
Although modern humans had arrived in the region by around 47,000 years ago, none of the Neanderthal genomes showed traces of recent human DNA.
“Our results add to a striking asymmetry,” Bossoms Mesa said.
“We repeatedly find Neanderthal ancestry in early modern humans, but so far, we have not found clear evidence of recent modern human ancestry in late Neanderthals.”
The scientists also tested the theory that Neanderthals were gradually weakened by accumulating genetic defects.
Comparing early and late Neanderthals, they found no meaningful increase in harmful mutations over time, undermining the notion that genetic deterioration drove their extinction.
What ultimately doomed the Neanderthals remains an open question.
But this study makes clear that, at least in northwestern Europe, their final millennia were not defined by biological collapse.
“This study highlights the power of ancient DNA to reveal variation within Neanderthals on a much finer scale than was previously possible,” said Dr. Janet Kelso, also from the Max Planck Institute for Evolutionary Anthropology.
“Rather than viewing late Neanderthals as a single declining population, we are beginning to recognize a more complex picture of regional diversity, connectivity, and population history.”
The findings appear this week in the journal Nature.
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A. Bossoms Mesa et al. Genetic diversity of late Neanderthals in northwestern Europe. Nature, published online June 24, 2026; doi: 10.1038/s41586-026-10625-1
