A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34
Honeybees never sleep.
276
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
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
Bats sleep 18-20 hours per day.
5
Those who get out of bed by 7am are more likely to be thinner and happier.
20
The strangers in your dreams are actually people that you've seen in real life.
50