They usually eat rotting fruits and vegetables. They are known to eat decaying meat while laying eggs in dead fruit as well.

Uh, ... fruit. If you want to raise some, mashed bananas. If you want to catch and kill them, vinegar.

Just about anything really. Though they do like to eat wheat, flour, and decaying fruit.

Time flies like an arrow, fruit flies like a banana.

from Groucho Marx

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