SSS 2011-07-07

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(Chirping sound.) That may not sound likemuch–but it’s the loudest animal in the world. For its size, that is. Theinsect called the water boatman is two millimeters long. And these peeps can beheard from a stream bottom by the human ear.

 

Animals are generally constrained¹ by themechanics of size. But small creatures need to be heard as well. Researchersthought some freshwater species might rely on sound because of poor visibility.So they collected water boatmen from a stream and pond in France. Theyrecorded 13 males doing their thing. They measured the sound level and theinsects’ bodies. And they compared those figures with 227 other loud species,like elephants. And relative to its body, the little water boatman made thebiggest racket, maxing out at 99 decibels². The research was published in thejournal Public Library of Science One. 

 

The scientists say they haven’t figured outexactly how the tiny creature produces such volume–in part it comes fromrubbing part of its genitalia against its abdomen³. But understanding theamplification could help us improve our own acoustic⁴ technology. Usingdifferent techniques, of course.

 

Thanks for the minute. For ScientificAmerican’s 60-Second Science. I'm Cynthia Graber .

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