A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
If you hold farts in during the day, they'll just come out when you sleep.
16
Sleeping on the job is acceptable in Japan. It is viewed as exhaustion from working hard. Some people fake it to look committed to their job.
57
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
Bats sleep 18-20 hours per day.
5
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193