A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
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
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15
You can reschedule your sleeping pattern by not eating 12-16 hours before you want to be awake. Upon eating after this time period, your internal clock will reset to a new day, with the time of your first meal being interpreted as "morning".
11
Cows can sleep standing up, but they can only dream lying down.
745