One reason that kittens sleep so much is because a growth hormone is released only during sleep.
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A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
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Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
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The average person falls asleep in seven minutes.
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Dieters who sleep more take off more fat that those who sleep less.
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The human brain is more active during sleep than during the day.
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