In a Panamanian pond, male t ngara frogs (Physalaemus pustulosus) gather in choruses, giving their "advertisement" call to the females that move among them. If a female chooses to make physical contact with a male, he will clasp her and eventually fertilize her eggs. But in vying for the females, the males whose calls are most attractive may also attract the interest of another creature: the fringe-lipped bat, a frog eater. In TheT...