Bats sleep 18-20 hours per day.
5
Lack of water is the #1 trigger of daytime fatigue.
148
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
The higher someone’s I.Q. the more likely they are to be sleep deprived.
29