Navy Studies Cicadas For Their Amplifying Sound Technique
LINDA WERTHEIMER, HOST:
Along the East Coast, lots of people are being serenaded by cicadas. Actually, they're just hearing the males. After 17 years of sleeping underground, millions of the winged insects are out there looking for mates. If these insects sound loud to you, that's because they are.
In fact, as NPR's Elizabeth Shogren reports, they are so loud the Navy is trying to borrow their technique for amplifying sound.
(SOUNDBITE OF A CICADA)
ELIZABETH SHOGREN, BYLINE: That's the sound of a male cicada trying to attract a mate.
DERKE HUGHES: It's just like crude, construction worker guys, you know...
HUGHES: ...hollering at women as they go by - it's really all that is.
SHOGREN: Navy engineer Derke Hughes recorded it. The sound comes from the back end of the bug, under its wings. Hughes says it's amazing what the bug does to make its call.
HUGHES: I always use the analogy with the human body. It's just like having your rib structure and having an internal muscle that pulls it inwards, so that each one of your ribs were to, like, sort of snap inwards. So you'd sort of be concaved and then it releases it. And then it pop back to regular form.
SHOGREN: Hughes has been studying cicadas for several years to try to learn how a thing smaller than your thumb makes such a loud noise. With the help of lasers he was able to measure how rapidly the bug makes these contortions, and figure out that the two sides of the bug don't squeeze in at the same time.
HUGHES: It's like left - right, left - right.
SHOGREN: What interests Hughes is how cicadas amplify their song so effectively and efficiently. Maybe that could help Navy submarines do a better job of sending messages under water.
HUGHES: We could actually benefit from the fact that they're small in size, but they've figured out how to talk to ladies that are, you know, as much as two football fields away.
SHOGREN: He's even done an experiment comparing them to a stereo speaker and the bug outperformed it, vindicating all the time Hughes has spent chasing cicadas with butterfly nets.
But there've been bumps too. This week, a collaborator presented Hughes's research at an international conference. Hughes stayed home because of federal budget cuts.
Elizabeth Shogren, NPR News, Washington.