The jungle is a noisy place, but one little animal has found a clever way to be heard. The 4-gram Spix’s disk-winged bat (Thyroptera tricolor) roosts in newly sprouted leaves of tropical plants, using their temporarily curled shape to hide from predators. Flying bats looking for a roost send out high-pitched inquiry calls, while their already-nested friends—like the one in the photo above—emit response calls to invite them in. Now, researchers in Costa Rica have found that the tube-shaped leaves may make both kinds of calls easier for other bats to hear. For a bat issuing response calls from within a roost, the leaf acts like a megaphone, amplifying its invitations by 1 to 2 decibels. The leaves also act like an ear horn; inquiry calls made by airborne bats looking for a roost were up to 10 decibels louder inside the nest than they were outside, the team reports today in the Proceedings of the Royal Society B. The researchers calculate that such an effect can boost an inquiry call’s range by up to 30 additional meters, helping bats stay together as a group throughout their near-constant house-hunting: Because the leaves quickly unfurl, the bats must find new roosting sites every day.
ScienceShot: Bats Use Megaphones in Jungle
Posted in Plants & Animals