47% of people have a nightmare at least once a month.
186
The higher someone’s I.Q. the more likely they are to be sleep deprived.
29
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
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
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The strangers in your dreams are actually people that you've seen in real life.
50