The strangers in your dreams are actually people that you've seen in real life.
50
Termites work 24 hours per day and they do not sleep.
57
Bats sleep 18-20 hours per day.
5
People who sleep late have more mental stamina and can outperform early risers.
33
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
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