Insects Hear Sounds We Do Not Hear.

Star (Christchurch), Issue 19269, 5 January 1931, Page 6

Insects Hear Sounds We Do Not Hear.

Nature Notes

By James Drummond, F.L.S., F.Z.S. EARS of crickets and grasshoppers are taut membranes, sometimes placed in the forelegs below the knee. Large volumes of sound cause the membranes to vibrate and make records.

In conjunction with these organs there are minute and complicated organs that detect delicate sound-waves. Although diverse in form, the more delicate organs all have a specialised nerve-cell that contains a tiny rod, which vibrates in response to the stimulus of sound. In contact with each organ there often is a disc or pit in the skin. Vibrations are received by the disc or pit, are transferred to the rod, and from the rod to the nervous system. In this way, these and other insects seem to hear sounds inaudible to human ears. A cricket has been heard to chirp at the rate of about ninety times a minute all night long. In a night of twelve hours it chirped 64,800 times, a sustained muscular effort—the music is instrumental, not vocal —of no mean standard. It was presumed at one time that insects performed to attract the opposite sex. Sex may enter into the question, but sex alone does not answer the question why insects are musical. Usually the males only are musical. Birds, the world’s greatest vocalists, apparently sing mainly because they like to sing. Insects play—they do not sing—mainly because they like to play. They love the manifold soft notes, which gratify them beyond measure.