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
The average cat sleeps about 2/3 of the day.
203
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
Lack of water is the #1 trigger of daytime fatigue.
148