Cows can sleep standing up, but they can only dream lying down.
745
47% of people have a nightmare at least once a month.
186
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Honeybees never sleep.
276
The strangers in your dreams are actually people that you've seen in real life.
50
Bats sleep 18-20 hours per day.
5
The human brain is more active during sleep than during the day.
28
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