PScientists reveal how bats learn to identify which prey is safe to eat

Summary

A fringe-lipped bat, Trachops cirrhosus, approaches a Fitzinger's robber frog, Craugastor fitzingeri, in Panama. This species of bat eavesdrops on the mating calls that male frogs produce to attract females, and uses these frog calls to detect, assess and localize its prey. Young bats do not share the same responses to frog mating calls that adults do; juveniles must acquire the ability to discriminate which frog calls signify palatable and poisonous prey. Credit: Merlin Tuttle Scientists at the Smithsonian Tropical Research Institute (STRI) found that the fringe-lipped bat, known to eavesdrop on frog and toad mating calls to find its prey, learns to distinguish between palatable and unpalatable frogs and toads through experience. The findings, published in the Proceedings of the Royal Society B, provide the first evidence that eavesdropping predators fine-tune their hunting cues over the course of their development. To source their food, some predators eavesdrop on calls emitted by prey. Fringe-lipped bats, which range from Panama to Brazil, are some of the most skilled eavesdroppers in the world. They are attuned to the sexual advertisement calls of over a dozen frog and toad species that live in their habitat. If a fringe-lipped bat hears a call, it will fly toward the sound within seconds. However, just like some incoming calls on people's cell phones originate from scammers, not every frog or toad call guarantees a safe and healthy meal—if a frog is too large or emits a toxin, the prey can pose a danger to the bat. A fringe-lipped bat, Trachops cirrhosus, responds to the calls of the túngara frog, Engystomops pustulosus, one of its preferred prey species. First, the bat hears the call of a single male túngara frog, producing a complex call (a 'whine' plus multiple 'chucks'.) Then, the bat hears the cacophony of a large túngara frog chorus, with many male túngara frogs acoustically competing for females at once. Credit: Joseph See Fringe-lipped bats have adapted...