Bats sleep 18-20 hours per day.
5
The strangers in your dreams are actually people that you've seen in real life.
50
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
The average cat sleeps about 2/3 of the day.
203
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Lack of water is the #1 trigger of daytime fatigue.
148