An immature ('nymph') cicada. They live in the soil and feed from the roots of plants by sucking the juices out of them. When a nymph is ready to change into the adult form, it will burrow up and emerge from the soil (usually after rain) and climb up a tree trunk, plant stem or even a fence or wall. It will stop, then the skin splits along the back and the cicada slowly emerges, leaving the empty 'shell'. The fresh adult cicada has crumpled wings at first, so it has to wait for them to expand and harden before it can fly.