It may plague your summer peaches and plums, but the fruit fly is "one of the most important animals" in medical research, says conservationist Anne Sverdrup-Thygeson.
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Different parts of the brain aren't always in the same stage of sleep at the same time, notes neurologist and author Guy Leschziner. When this happens, an individual might order a pizza or go out for a drive — while technically still being fast asleep.
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