Cows can sleep standing up, but they can only dream lying down.
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A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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Dieters who sleep more take off more fat that those who sleep less.
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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
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
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In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13