Cows can sleep standing up, but they can only dream lying down.
745
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
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
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
Termites work 24 hours per day and they do not sleep.
57
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149