Cows can sleep standing up, but they can only dream lying down.
745
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
People who sleep late have more mental stamina and can outperform early risers.
33
Lack of water is the #1 trigger of daytime fatigue.
148
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34