Songs of Achatina snails
Snails can sometimes reproduce various sounds reminding sharp or
lingering squeak, singing, muffled mutter - in general, they can "sing".
Here is the record of such sounds, in МР3 format. I didn’t do anything with
these "songs", except for amplification of a signal.
The snail Sofia performs:
The origin of these sounds is rather simple. In a quiet
condition the body (leg) of a snail goes beyond its shell a little. Its respiratory
aperture is open and air easily comes to lungs. When the snail, for example, is
frightened, edges of a respiratory aperture are closed, and the body of a snail draws into
a shell. Air under pressure leaves through the closed respiratory aperture, forcing his
edges to vibrate.
By the same principle vocal chords of the person and many animals work.
In pictures: on the right - the respiratory aperture of a snail
Achatina snail is open, on the left - it is closed, and the snail can produce a sound.