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
A new parent will lose about 1055.6 hours of sleep in the first year of their child's life - almost 44 days!
6
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
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