The Dog Day Cicadas emerge as adults during the dog days of summer and begin serenading. In much of the midwestern US, cicadas provide the loudest background sounds. There are many species of cicada, all singing different songs and sometimes chorusing at different times.
Cicadas have incomplete metamorphosis. Immatures resemble wingless adults. They feed underground on fluid from tree roots. Their front legs are fossorial (modified for digging). They have compound eyes and ocelli, but it is not clear that they are useful in the dark underground. Their forward facing antennae are probably used for detecting carbon dioxide and other volatiles that indicate the location of roots. Numerous hairs on the front of their head probably provide information about their food.
Cicadas are difficult to study because of their extended (1-2 years), cryptic underground life and the difficulty in keeping them in colony. They take nutrients from trees, but trees, if not stressed for water, appear to tolerate them.