Stridulation in Leaf-Cutting Ants.
The leaf-cutting ant Atta caphaloes L. stridulates whenever it is prevented from moving freely. Although audible to the human ear, the airborne sound produced has its main energy concentrated between 20 and 60 kilocycles per second. However, it is not the airborne, but the groundconducted stridulation sound that acts as a distress alarm: a stridulating ant attracts other workers, and if the "calling" ant is covered by earth, intensive digging is released in the attracted nest mates.
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