The chirping of crickets - to some an annoyance, to others, music. In China, a cricket singing in the home is a sign of good luck. The name cricket actually comes from the French word criquer, meaning "little creaker." Just how do crickets produce and project such a boisterous song?
Only male crickets actually produce sounds, and not all species of crickets chirp. Though some human cultures revere the song of the cricket, he's not singing for our enjoyment. The male crickets chirps to attract a female mate. The female responds only to the unique, characteristic sound of her own species. Crickets also chirp to establish their territories and defend it against competing males.
Crickets produce by rubbing their wings together. At the base of the forewing, a thick, ridged vein acts as a file. The upper surface of the forewing is hardened, like a scraper. When the male cricket wants to call for a mate, he lift his wings and pulls the file of one wing across the scraper of the other. The thin, papery portions of the wings vibrate, amplifying the sound. This method of producing sound is called stridulation (which means "to make a harsh sound" in Latin).
Some crickets, such as mole crickets, dig tunnels in the ground with megaphone-shaped entrances. When the males sing from just inside their burrow openings, the shape of the tunnel amplifies the sound.
Crickets actually produce different calls for different purposes. The calling song, which may be heard for distances up to a mile, helps the female find the male. Once she is near, the male switches to a courtship song to convince her to mate with him. And, in some cases, the male also sings a post-copulation celebratory song.
And here's an interesting factoid. According to May R. Berenbaum, Head of the Entomology Department at the University of Illinois at Urbana-Champaign, most crickets in the family Gryllidae are right-winged! These crickets show a preference for drawing their right wing across their left.
- Bugs in the System, by May R. Berenbaum
- The Handy Bug Answer Book, by Gilbert Waldbauer