A female housefly can lay approximately 9,000 eggs in a lifetime! The eggs are laid on or near meat, often dead animals. Within a day, larvae (maggots) hatch from the eggs; they live and feed on dead and decaying organic material, such as garbage, carrion or faeces. They are pale-whitish, and have no legs. Their life cycle is from 14 hours to 36 hours.
At the end of their third instar, the maggots crawl to a dry, cool place and turn into pupae. These are coloured reddish-brown and about 8 mm long. From the pupae emerge adult flies. The whole cycle is known as complete metamorphosis.
Adults live from two weeks to a month in the wild. After they come out from the pupae, the flies do not grow. Small flies of the same species did not get enough food when they were larvae. The function of adult insects is to reproduce.
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