47% of people have a nightmare at least once a month.
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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 average person falls asleep in seven minutes.
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Sea otters hold hands while sleeping so they don’t drift away from each other.
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Some people have a "natural alarm clock" allowing them to wake up when they want. This is actually caused by a burst of the stress hormone adrenocorticotropin.
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People who sleep late have more mental stamina and can outperform early risers.
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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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