If you hold farts in during the day, they'll just come out when you sleep.
16
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
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
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
Bats sleep 18-20 hours per day.
5
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13