A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
People who sleep late have more mental stamina and can outperform early risers.
33
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
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The average person falls asleep in seven minutes.
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