Cows can sleep standing up, but they can only dream lying down.
745
The average cat sleeps about 2/3 of the day.
203
The strangers in your dreams are actually people that you've seen in real life.
50
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Dieters who sleep more take off more fat that those who sleep less.
159
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28