Crickets Craft Tools Out Of Leaves To Make Their Mating Call Louder, Scientists Say
Crickets Craft Tools Out Of Leaves To Make Their Mating Call Louder, Scientists Say
Researchers discovered that smaller crickets poke holes in leaves to amplify the sounds of their chirps, which appears to give them greater success at mating.
(SOUNDBITE OF CRICKET CHIRPING)
AILSA CHANG, HOST:
Male tree crickets advertise their availability by rubbing their wings together to chirp. And larger, louder males find more favor with the females.
MARY LOUISE KELLY, HOST:
But smaller, less desirable males do have a trick to juice up their prospects - they amplify their chirps by punching a hole in a leaf and sticking their head through it. Rittik Deb of India's National Center for Biological Sciences described it like this.
RITTIK DEB: You know those collars that they put on dogs when they're putting some vaccine or something on the dogs? It looks something like that.
CHANG: This technique, known as baffling, can more than double the volume of a cricket's mating call. Ed Baker of the Natural History Museum in London says the leaf works sort of like a loudspeaker.
ED BAKER: You effectively increase the size of the wing, which makes the sound appear to be louder.
KELLY: Here are two recordings - same cricket. First, without the leaf.
(SOUNDBITE OF CRICKET CHIRPING)
CHANG: All right, now with the leaf.
(SOUNDBITE OF CRICKET CHIRPING)
CHANG: Whoa. I got to turn down my headphones now.
(LAUGHTER)
KELLY: This phenomenon was first documented in the mid-1970s. But what Deb's team found is it has real consequences for small crickets. His team estimates quieter males can go from zero dates a night to three simply by cranking the volume of their calls up to about 11.
CHANG: And once female crickets are reeled in, they hang around longer, too, which gives smaller males a better chance at passing on their genes. The results were published by the Royal Society.
KELLY: A question, though - if baffling works so well, why don't all crickets use it? Deb says loud males don't have much to gain.
DEB: The loud males are already getting the optimal number of mates they can mate with within a night.
CHANG: (Laughter) And though we might think of primates or crows as the smart tool-using animals, Deb says crickets deserve some credit, too.
DEB: The have the tiniest of all the brains that is possible, and yet they produce such complex behaviors.
CHANG: The chance of finding a mate, it seems, is all it takes to turn crickets into audio engineers.
(SOUNDBITE OF THE MIDNIGHT SONG, "YOUTH")
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