Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
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Bats sleep 18-20 hours per day.
5
Termites work 24 hours per day and they do not sleep.
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Lack of water is the #1 trigger of daytime fatigue.
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One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
Cows can sleep standing up, but they can only dream lying down.
745
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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