A female lays about 500 eggs on waste, decaying organic matter. After mating, the males die within a few days. Females flies live an average of 20 days.
The larva comes out of the egg after only 1 day. It’s called a maggot. It then has a lifetime of ten days. It grows very fast; It creates a cocoon in which it will stay from a few hours to several days. Meanwhile, it turns into a fly.
The fly that comes out of the cocoon will spend half of its time feeding, then the second half breeding.
From autumn to spring, the larvae will overwinter in their cocoon. This phase is called diapause. A large number of fly die at this time.
The most common fly is the domestic fly.