Eve: How the Female Body Drove 200 Million Years of Human Evolution

by Cat Bohannon

Certain members of anthropology and biology departments in the 1980s and 1990s wondered, What’s with all those women synchronizing their periods when they live together? That must have an evolutionary advantage, right? One ambitious fellow (published by Yale University Press, no less, in 1991) decided this meant that ancient women somehow evolved to go on collective sex strikes by synchronizing their periods, thereby enabling/encouraging men (less distracted by the pressing desire to screw) to go out and hunt and forage. This, the author theorized, was the root of all human culture. In effect, he argues that humans build cool stuff like the Pyramids and rocket ships because women get periods and therefore don’t have sex for a set number of days per month.[*41]