Bats sleep 18-20 hours per day.
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If you hold farts in during the day, they'll just come out when you sleep.
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The human brain is more active during sleep than during the day.
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A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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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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You can reschedule your sleeping pattern by not eating 12-16 hours before you want to be awake. Upon eating after this time period, your internal clock will reset to a new day, with the time of your first meal being interpreted as "morning".
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