You burn more calories sleeping than you do watching television.
348
Bats sleep 18-20 hours per day.
5
Cows can sleep standing up, but they can only dream lying down.
745
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
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
If you hold farts in during the day, they'll just come out when you sleep.
16
Honeybees never sleep.
276