Crickets chirp their songs for a specific purpose. Like many animals they are viciously territorial, engaging in often fatal fights in defense of their space and reproductive rights. But those not willing to fight have their own devious way of finding mates. And they DO bite, just not often.
Some say Crickets bite. I know they bite. They bit me. As a kid visiting my much older sister, who lived on a major two lane highway in Michigan (the only kind of major highways there were then) where there were a lot of lakes, my nephews and I, who are about my age, would dig worms and catch Crickets for fish bait, put up a couple signs and sell the bait out by the road. It paid for a Tarzan movie.
While catching Crickets I got bit a couple of times, on the webbing between my fingers. It swelled and hurt and I told everyone that Crickets bite. They said things like, “Sure they do, and so do worms.” But I never doubted, throughout my life, that Crickets bite. So, while researching Crickets for this article I specifically looked for evidence that crickets bite. I found lots of evidence of it. Crickets DO bite and it can be painful if they bite tender skin, such as between the fingers. I am vindicated! It did qualify that it does not happen often but, occasionally, Crickets bite.
Crickets also chirp and the thing they chirp is called a song. They get really good at these songs because they only have to learn four of them. Only the males chirp. I guess they have only four things in life to chirp about. The first song is chirped when he is alone and wants the female population to notice him and wants the other males to leave him alone. The second, a very quiet song, is chirped when he has a specific female in view and he is courting her. The third song is called the copulatory song which the male crickets, being quite romantic, sing while mating. The fourth song is a display of aggression towards another male Cricket.
The weather affects the Cricket’s singing. The warmer the temperatures the faster the Crickets chirp. In fact, the chirp speed (number of chirps per minute) correlates so precisely with temperature that researchers could accurately tell the temperature by listening to Cricket chirps. The formula used to predict temperature looks like this; Temperature=50+(Number of chirps per minute-40)/4.
I can imagine that my daughters, sometime during their childhoods, asked me how Crickets make that strange sound. I probably told them what I and a few billion other people thought was true, “They rub their legs together”. I was wrong, as often I am when I trust hearsay. They rub their wings together. The underside of each Cricket’s forewing cover has a vein that has grown teeth on it, much like a comb. When the top of the opposite wing, which is equipped with a kind of scrapper, is rubbed over the teeth the effect is much like rubbing your finger over the teeth of a comb. The Cricket’s wings are held erect while making this movement, so the membrane of the wings serves as the sounding board to project the sound backwards. The Cricket, while chirping, rotates his body, head to tail, every six seconds, to make sure he covers the area well with his pleas. The females, although they are deaf, have tympanic membranes just below their front knees (they probably think it strange that we park our ears on the sides of our heads) that pick up the sounds.