Neanderthal Extinction Linked to Lead Toxicity,Study Suggests
SAN DIEGO,CA – October 16,2025 – A new study published in Science Advances suggests that lead exposure may have played a notable,previously unrecognized role in the extinction of Neanderthals. Researchers at the University of California, San Diego, found that a genetic variant present in Neanderthals made their brain organoids more susceptible to developmental damage from lead exposure compared to those with the modern human version of the gene NOVA1.
The research team, led by Alysson Muotri, created brain organoids – miniature, simplified versions of the brain – carrying either the Neanderthal or modern human NOVA1 gene.When exposed to levels of lead comparable to those estimated during prehistoric times, the Neanderthal organoids exhibited significant disruptions in key signaling pathways and genes, including FOXP2, a gene crucial for speech growth. The modern human variant, however, showed greater resilience. “This suggests that our NOVA1 variant protects us better against neurological damage caused by lead,” the team stated.
This finding offers a potential clarification for the evolutionary advantage of homo sapiens over Neanderthals. The study proposes that lead toxicity, a widespread environmental factor throughout human history, may have triggered genetic changes that enhanced survival and linguistic capabilities in our ancestors. “This is an remarkable example of how an environmental factor – in this case lead toxicity – may have triggered genetic changes that improved survival and our ability to communicate linguistically,” said Muotri.
The researchers hypothesize that Neanderthals,lacking the protective NOVA1 variant,may have suffered greater neurological impairment from lead exposure,possibly hindering their cognitive development and interaction skills. This could have contributed to their eventual decline and extinction as Homo sapiens, with superior communication abilities, thrived. The study underscores the complex interplay between genetics, habitat, and the course of human evolution. (Science Advances, 2025; doi: 10.1126/sciadv.adr1524)
