Do Flies Really Have 24-Hour Lifespans?

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“I’ve only got 24 hours of living, and I ain’t gonna waste ‘em here!” groans a disgruntled housefly during a hilarious scene in Pixar’s A Bug’s Life. But do those pesky insects really brandish a day-long life expectancy?

The short answer is no. Contrary to popular belief, the common fly (Musca domestica) in its adult form can hope to keep on buzzing for a few weeks before heading up to that big sugar cube in the sky … assuming it never meets the business end of a swatter. According to entomologists, mature houseflies generally live for 15 to 25 days. Some specimens manage to hold on even longer: Several have been documented reaching the ripe old age of two months!

Like most of their brethren, these creatures undergo an intricate life cycle involving many stages. To make a long story short, check out this brief visual summary (narrated for your convenience):

Here’s the process in a nutshell: Females lay eggs which quickly hatch into larvae (aka maggots). These worm-like babies get larger and larger until they eventually enter the “pupal” phase. At this point in their lives, they grow hardened outer shells (these shouldn’t be confused with cocoons, which are very different structures). Inside this casing, they remain dormant while gradually developing adult features such as legs and wings. Eventually, a fully-grown fly emerges from this casing and begins looking for a mate.

How long does the whole shebang take? Usually, an individual goes from maggot to adult in a meager 7 to 10 days. Talk about living fast!