Observed: Trinidadian guppy Poecilia reticulata
Coercion: Male guppies breed ceaselessly, even harassing nonreceptive females.
Camouflage: But females have a way to rebuff unwanted advances, according to a new study: hang out with females that are ready to mate. Receptive females’ pheromones drew males’ attention away from nonreceptive females that wanted none of it. “I would expect that this strategy would be seen in other species,” says Safi Darden of the University of Exeter in Britain, “where females face similar amounts of unwanted sexual attention from males.”