London, Oct 11: Mice court one another with ultrasonic love songs
that are iudible to the human ear, and researchers, including one of
Indian origin, have found that when mice ‘sing’, they use a mechanism
similar to that seen in the engines of supersonic jets. “Mice seem to be
doing something very complicated and clever to make ultrasound,” said
study co–author Anurag Agarwal from University of Cambridge. Mice, rats
and many other rodents produce ultrasonic songs that they use for
attracting mates and for territorial defence. These ‘singing’ mice are
often used to study communication disorders in humans, such as
stuttering.
However, until now it was not understood how mice can make these
ultrasonic sounds, which may aid in the development of more effective
animal models for studying human speech disorders.
“Mice make ultrasound in a way never found before in any animal,”
lead author of the study Ele Mahrt from the Washington State
University noted. The new research showed that mice point a small air
jet coming from the windpipe against the inner wall of the larynx,
causing a resonce 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. “This mechanism is known only to
produce sound in supersonic flow applications, such as vertical takeoff
and landing with jet engines, or high–speed subsonic flows, such as jets
for rapid cooling of electrical components and turbines,” Agarwal
explained. (IANS)