A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
Bats sleep 18-20 hours per day.
5
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
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
You burn more calories sleeping than you do watching television.
348
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
The average cat sleeps about 2/3 of the day.
203