Among scientists at the university of New Mexico that spring, rape was in the air. One of the professors, biologist Randy Thornhill, had just coauthored A Natural History of Rape: Biological Bases of Sexual Coercion, which argued that rape is (in the vernacular of evolutionary biology) an adaptation, a trait encoded by genes that confers an advantage on anyone who possesses them. Back in the late Pleistocene epoch 100,000 years ago, the 2000 book contended, men who carried rape genes had a reproductive and evolutionary edge over men who did not: they sired children not only with willing mates, but...
