The Secret Sex Lives of Female Chimpanzees

Leaving aside the strangeness of a research project that involves watching monkeys fucking all day, scientists studying chimpanzees in Uganda have made the interesting discovery that our closest animal relatives know when to be discreet about their sex lives. Although female chimps will advertise that they're in estrus (i.e., fertile) with a specific call, they only occasionally make noise during sex. In fact, if there are higher-status female chimps around or if they are mating with lower status-males (which was about two-thirds of the time in the study), female chimps are silent while mating. It's only when they're having sex with high-status males that they advertise that fact vocally. Perhaps the Budongo Forest of Uganda is more like Hollywood or New York than anyone realized? [NY Times]