Overview
- The PNAS study, released Monday, reports that estimated brain differences between Neanderthals and early modern humans fall within the range seen among people today.
- Researchers compared MRI scans from about 200 Americans of European ancestry and about 200 Han Chinese volunteers and found larger group differences in 9 of 13 brain regions than those estimated between Neanderthals and Homo sapiens.
- The authors argue that small anatomical gaps would not account for a rapid replacement and point instead to demography and genetic swamping, where interbreeding diluted Neanderthal genes in larger Homo sapiens populations.
- Separate modeling by Ariane Burke’s team suggests climate swings, geography, and weaker social links between Neanderthal groups reduced resilience, with more connected Homo sapiens networks offering a survival edge.
- Archaeological finds of fire use, adhesives, symbolic art, tools, and tailored clothing support complex Neanderthal behavior, and the weak link between brain shape and intelligence in humans cautions against reading cognition from skulls.