Sea otters hold hands while sleeping so they don’t drift away from each other.
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A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
There's a love mattress that is specifically designed for couples who sleep on each other's arms.
12
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
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.
15
The higher someone’s I.Q. the more likely they are to be sleep deprived.
29
The average person falls asleep in seven minutes.
115