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