One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
Bats sleep 18-20 hours per day.
5
If you hold farts in during the day, they'll just come out when you sleep.
16
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
You can reschedule your sleeping pattern by not eating 12-16 hours before you want to be awake. Upon eating after this time period, your internal clock will reset to a new day, with the time of your first meal being interpreted as "morning".
11
The human brain is more active during sleep than during the day.
28
Honeybees never sleep.
276
The strangers in your dreams are actually people that you've seen in real life.
50