The human brain is more active during sleep than during the day.
28
Termites work 24 hours per day and they do not sleep.
57
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
A new baby usually deprives each of it's parents around 350-400 hours of sleep in the first year. That is one entire nights sleep per week, per parent.
194
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34