Sea otters hold hands while sleeping so they don’t drift away from each other.
104
Lack of water is the #1 trigger of daytime fatigue.
148
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
The strangers in your dreams are actually people that you've seen in real life.
50
Termites work 24 hours per day and they do not sleep.
57