Diptera is an order of insects which include all suborders and species of flies: the housefly, the fleshfly, hematophagous flies (tse-tse fly, horsefly), the blowfly, fruit fly, as well as mosquitoes, gnats, midges, etc. The distinctive feature of the diptera order of insects is that they have only two anterior membranous wings, with which they fly, and two tiny underdeveloped posterior wings, which they use for balancing and as gyroscopes with which they control the flight direction. Thus, adapted for flights, diptera insects generally have short stream-lined bodies. The female lays her eggs as close to the food source as possible. After a brief time, the larvae hatch out of the eggs and begin to eat enourmous amount of foood. When they have fully grown, the larvae become pupae. After several days of metamorphic development, flies come out of the pupae.