One Ribbit Too Many

Female animals flock to the ridiculous: the gangly antlered moose, the blue-bottomed baboon, and the garish peacock. But a new study suggests that túngara frog (Physalaemus pustulosus) females from Latin America keep that machismo posturing from turning too bizarre. Males of this species serenade their would-be mates late into the night, mixing high-pitched "whines" with short "clucks." Females, in turn, prefer the suitors that cluck the most but only up to a point. Males, it seems, overdo their arias during long song-a-thons by continuously trying to one-up rivals, and their amphibian Aphrodites aren't able to follow along. The more complex the songs get, in fact, the less the ladies can distinguish good from poor singers, researchers report online today in Science. That limitation may stop the frog princes from evolving increasingly elaborate songs, preventing the inevitable all-frog review of Madame Butterfly. Shortcomings in female perception may similarly slow the ambitious displays of males in a host of other species, the team suggests, although moose haven't seen to have gotten the message.