A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15
Cows can sleep standing up, but they can only dream lying down.
745
Those who get out of bed by 7am are more likely to be thinner and happier.
20
"Dysania" is the state of finding it hard getting up out of bed in the morning.
33
Bats sleep 18-20 hours per day.
5