The order Diptera includes many familiar insects such as gnats, flies and mosquitoes. There are over 100,000 species and they go through complete metamorphosis. They have piercing, sucking or sponging type of mouthparts, and they are known for only having one pair of wings. They also have diverse feeding habits - some like houseflies and flesh-flies feed on garbage, manure, or dead animals, and some like hoverflies feed on nectar from flowers. Most larvae have no legs.