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
The human brain is more active during sleep than during the day.
28
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
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
You burn more calories sleeping than you do watching television.
348
The average person falls asleep in seven minutes.
115