Termites work 24 hours per day and they do not sleep.
57
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
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
If you hold farts in during the day, they'll just come out when you sleep.
16
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
Cows can sleep standing up, but they can only dream lying down.
745