The human brain is more active during sleep than during the day.
28
You burn more calories sleeping than you do watching television.
348
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
If you hold farts in during the day, they'll just come out when you sleep.
16
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28