Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
Bats sleep 18-20 hours per day.
5
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
You can reschedule your sleeping pattern by not eating 12-16 hours before you want to be awake. Upon eating after this time period, your internal clock will reset to a new day, with the time of your first meal being interpreted as "morning".
11
You burn more calories sleeping than you do watching television.
348
The human brain is more active during sleep than during the day.
28
Cows can sleep standing up, but they can only dream lying down.
745