A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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People who sleep late have more mental stamina and can outperform early risers.
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Those who get out of bed by 7am are more likely to be thinner and happier.
20
The human brain is more active during sleep than during the day.
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Bats sleep 18-20 hours per day.
5
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".
11
Sea otters hold hands while sleeping so they don’t drift away from each other.
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