You forget 90% of your dreams.
256
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
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
People who sleep late have more mental stamina and can outperform early risers.
33
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
Sea otters hold hands while sleeping so they don’t drift away from each other.
104