in case you ever wondered:
Cicadas are notorious singers. The song is a mating call produced by the males only. Each species has its own distinctive call and only attracts females of its own kind even though rather similar species may co-exist.
Cicadas are the only insects to have developed such an effective and specialised means of producing sound. Some large species produce a noise intensity in excess of 120 dB at close range (this is approaching the pain threshold of the human ear). In contrast, some small species have songs so high in pitch that the noise is beyond the range of our hearing.
The organs which produce sound are the tymbals, a pair of ribbed membranes at the base of the abdomen. Contracting the internal tymbal muscles causes the tymbals to buckle inwards and produces a pulse of sound. By relaxing these muscles, the tymbals pop back to their original position. In some cicada species, a pulse of sound is produced as each rib buckles.
Both male and female cicadas have organs for hearing. A pair of large, mirror-like membranes, the tympana, receive the sound. The tympana are connected to an auditory organ by a short tendon. When a male sings, it creases the tympana so that it won't be deafened by its own noise.
Many species of cicada sing during the heat of the day. Some cicada species only sing at dusk (Often these species are weak fliers) The loud noise produced by some day-singing cicadas actually repels birds, probably because the noise is painful to the birds' ears and interferes with their normal communication.