Overview
- The Nature study published June 24 sequenced DNA from 27 Neanderthal remains from Belgium and France and found these late northwestern Neanderthals were relatively diverse and showed low levels of inbreeding.
- Those genomes showed little to no trace of recent modern‑human ancestry despite long overlap with early Homo sapiens in the region, creating an asymmetry with examples of Neanderthal DNA found in early modern humans.
- The new results directly challenge theories that rising harmful mutations or a steady loss of genetic diversity were the main cause of Neanderthal disappearance in northwestern Europe.
- Earlier work led by Joshua Akey used a different method and modern genomes to identify at least three separate interbreeding pulses over roughly 250,000 years and reported detectable modern‑human ancestry inside some Neanderthal genomes.
- Taken together, the papers show a more complex, regionally varied picture of contact between Neanderthals and modern humans and underline the need for more ancient genomes and better analytical tools to settle timing, direction and biological effects of gene flow.