The emergence in the Neolithic of patrilineal social systems, in which children are affiliated with their father’s lineage, may explain a spectacular decline in the genetic diversity of the Y chromosome observed worldwide between 3,000 and 5,000 years ago.

In a study published today in Nature Communications, a team of scientists from the CNRS, MNHN and Université Paris Cité suggest that these patrilineal organizations had a greater impact on the Y chromosome than mortality during conflict.