That's amore: Mice 'sing when seeking sex'
Mice make whistling noises when seeking sex, research has found.
It was previously thought that these songs were either the result of a mechanism similar to that of a tea kettle, or of the resonance caused by the vibration of the vocal cords.
But a study co-authored at the University of Cambridge, UK, and published in the journal 'Current Biology' has found that when mice 'sing', they use a mechanism similar to that seen in the engines of supersonic jets, to attract mates and for territorial defence.
"Mice seem to be doing something very complicated and clever to make ultrasound," said study co-author Dr Anurag Agarwal.
"Mice make ultrasound in a way never found before in any animal," said Elena Mahrt, the study's lead author.
The researchers found that mice do not use vibrating vocal folds in their larynx to make their ultrasonic sounds.
Instead, they point a small air jet coming from the windpipe against the inner wall of the larynx, causing a resonance and producing an ultrasonic whistle.
Using ultra-high-speed video of 100,000 frames per second, the researchers showed that the vocal folds remain completely still while ultrasound was coming from the mouse's larynx.