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
You burn more calories sleeping than you do watching television.
348
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
Bats sleep 18-20 hours per day.
5
The higher someone’s I.Q. the more likely they are to be sleep deprived.
29
The human brain is more active during sleep than during the day.
28
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
