A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Honeybees never sleep.
276
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
"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
The average person falls asleep in seven minutes.
115
Sea otters hold hands while sleeping so they don’t drift away from each other.
104