Chirping Crickets

Crickets, family Gryllidae are insects somewhat related to grasshoppers, and more closely related to katydids or bush crickets. They have somewhat flattened bodies and long antennae. There are about 900 species of crickets. They tend to be nocturnal and are often confused with grasshoppers because they have a similar body structure including jumping hind legs. Crickets are harmless to humans.

Only the male crickets chirp. A large vein running along the bottom of each wing has "teeth," much like a comb does. The chirping sound is created by running the top of one wing along the teeth at the bottom of the other wing. As he does this, the cricket also holds the wings up and open, so that the wing membranes can act as acoustical sails. It is a popular myth that the cricket chirps by rubbing its legs together.

There are four types of cricket song: The calling song attracts females and repels other males, and is fairly loud. The courting song is used when a female cricket is near, and is a very quiet song. An aggressive song is triggered by chemoreceptors on the antennae that detect the near presence of another male cricket and a copulatory song is produced for a brief period after a successful mating.

You can tell the temperature by listening to the chirping of a cricket. The frequency of chirping varies according to temperature. The relationship between temperature and the rate of chirping is known as Dolbear's Law. Using this law it is possible to calculate the temperature in Fahrenheit by adding 40 to the number of chirps produced in 14 seconds by the snowy tree cricket common in the United States.

More about chirping crickets.