The rare infanticides turned out instead to be carefully calculated. And they were committed by males from outside the breeding group. “When I first did see infants missing, and then later I actually saw a male attack infants, it was very goal-directed stalking, as if by a shark. Day after day, hour after hour.” What was making a male commit this gruesome killing was the expectation that, without her baby, a mother would have to mate again. If he didn’t kill the infant, he would have to wait a year before she finished nursing and started ovulating. She couldn’t mate any sooner.
