You burn more calories sleeping than you do watching television.
348
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
Cows can sleep standing up, but they can only dream lying down.
745
The average cat sleeps about 2/3 of the day.
203
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
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The human brain is more active during sleep than during the day.
28
"Dysania" is the state of finding it hard getting up out of bed in the morning.
33