system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are worms developping on rotten food? They can't appear out of nowhere, so are they "there" when we eat food and appear in the right conditions?
gpt
People used to think that they just appeared out of nowhere: the theory of spontaneous generation. There were even recipes - for example, how to create bees. But of course we know now that the world doesn't work that way. Generally, when things rot, the "worms" you see are maggots. Maggots are the larvae of flies. So what happens is the rotting food attracts flies, which lay eggs, and those eggs then hatch. [edit:spelling]