Flies have a complex reproductive cycle. They lay their eggs on organic matter that decomposes, such as decaying food and dead animals. These eggs are white and less than one-half inch long. The young fly will hatch from the pupa in about eight to twenty hours, depending on the species.
Female flies can lay hundreds of eggs, each of which will develop into a fly within a few days. If there is sufficient food available, millions of flies can appear in a short time. The adults live for about 2 weeks, but there are some flies that live much longer than this. Flies can also give birth to live maggots, but eating them is not harmful.
Female flies lay eggs on decomposing organic matter. They also feed their larvae on other insects and plants. In addition to their food sources, some species feed their larvae on other insects, such as aphids. This means that they are considered beneficial pollinators.
In the pupa stage, flies begin to develop their wings and legs. During this time, they are usually dormant, but some species don’t leave their eggs in the same place.