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
You forget 90% of your dreams.
256
Cows can sleep standing up, but they can only dream lying down.
745
Bats sleep 18-20 hours per day.
5
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
Honeybees never sleep.
276
People who sleep late have more mental stamina and can outperform early risers.
33