Flies All Stages of Life
The development of flies involves a four-phase life cycle. Beginning as eggs, flies undergo larval and pupal stages before emerging as adults. The fly's life cycle begins when a fertilized female finds a suitable location for laying her eggs. The ideal egg site is material that the larvae will eat when they hatch from the egg. Examples of egg-laying sites might include a pile of trash, feces or other damp, decomposing organic material.
In some cases, fertilized eggs hatch within 24 hours. Upon hatching, larvae feed upon the organic material. Fly larvae eat for several days to weeks, storing enough protein and nutrients to last through their upcoming pupa stage.
When larvae are grown, they leave their food source and seek dry, dark places within which to pupate. During the pupal stage, flies develop from legless larvae into adults with six legs, compound eyes and a pair of wings. Development time from egg to adult vary depending on species, environmental conditions and abundance of food. Some flies can complete their development in the matter of a couple of weeks if conditions are right.