The Freeloading Boyfriends That Just Won’t Let Go

For male Santa Marta harlequin toads, sex is an exercise in patience.

The ping-pong-ball-size frogs, which are native to a mountainous strip in northern Colombia, spend most of their days milling about the region’s burbling brooks, hoping to chance upon a mate. They don’t often get lucky: Only rarely, for a few days a year around the start of the rainy season, will the species’ much-larger females venture down from the trees to flit through these loose froggy frats. That means the window of amorous opportunity is painfully tight, and “the probability of meeting is very low,” says Luis Alberto Rueda Solano, a biologist studying the toads at the Universityunattached female he sees that year—his one shot at shattering his celibacy until the rains come again.