A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
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
People who sleep late have more mental stamina and can outperform early risers.
33
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
Bats sleep 18-20 hours per day.
5
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15