Humans Can't Hear It But Mice Make Ultrasonic Sounds Steve Inskeep and Renee Montagne report on new research that shows the mechanism through which mice and rats squeak is similar to a supersonic jet engine.
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Humans Can't Hear It But Mice Make Ultrasonic Sounds

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Humans Can't Hear It But Mice Make Ultrasonic Sounds

Humans Can't Hear It But Mice Make Ultrasonic Sounds

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RENEE MONTAGNE, HOST:

And here's the kind of question a kid would ask. How does a mouse make this sound?

(SOUNDBITE OF MOUSE SQUEAKING)

MONTAGNE: That really is the squeak of a mouse. Some researchers tried to find out just how they did it.

ELENA MAHRT: We had an idea of some work done in the '70s.

MONTAGNE: Graduate student Elena Mahrt speaking via Skype - she says researchers already knew that mice made that sound by pushing air out of their bodies at supersonic speeds.

MAHRT: That it was a whistle mechanism. What we didn't know is exactly what kind of whistle it was and how it happened in their voice box at all.

STEVE INSKEEP, BYLINE: But it's not like the whistle of a tea kettle. Mahrt is the lead author of a new study that says mouse squeaks are actually produced more like the sound from a jet engine. By using a high-speed camera, they found out that the squeak has everything to do with the epiglottis.

MAHRT: The epiglottis is the flap that will flap closed over the windpipe when you swallow. And the jet of air comes out of the windpipe and hits the base of that.

INSKEEP: Causing the squeak.

(SOUNDBITE OF MOUSE SQUEAKING)

MONTAGNE: Anurag Agarwal at the University of Cambridge is one of the co-authors of the study in the latest issue of Current Biology. He says, think of it like - OK. If you've ever put your hand over one of those restroom hand dryers...

(SOUNDBITE OF HAND DRYER)

ANURAG AGARWAL: You can get a very loud noise, which is almost like a whistle. And that's something very similar to what the mice are doing.

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