“All these features of human sexuality—long-term sexual partnerships . . . private sex, concealed ovulation, extended female receptivity, sex for fun . . . constitute what we humans assume is normal sexuality,” Diamond explains. “But that proves to be a species-ist interpretation. By the standards of the world’s 4,300 other species of mammals, and even by the standards of our own closest relatives the great apes . . . we are the ones who are bizarre.”
