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Name: Shelley R Hasinoff
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A grade 3 student working on a project on houseflies would like to know if flies sleep and if so where do they sleep? Thanks for your help.

I'm no expert on the pests, but I'd say they don't. The problem, though, is that sleep is not easy to define even in humans. We don't understand what happens to our bodies when we sleep, how we sleep, or why (although there are ideas about each of these). I think sleep is basically defined as the unusual pattern in the electrical signals given off by the brains of people who say (later) that they've been asleep. Kind of a circular definition, eh? We can surmise that cats and dogs sleep because they act like sleeping people --- lay down, close their eyes, don't respond, snore and twitch when dreaming --- and they probably have similar patterns in the electrical signals from their brains, though I don't know. But with flies, now, they're so different that not seeing the same behavior doesn't say much. Still, I'd say they don't because the most convincing hypothesis I've heard about the reason for sleep is that it is part of learning, and I've also heard that flies are capable of learning anything at all. That's an argument, but by no means an answer. Sorry.

Christopher Grayce

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