A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
Lack of water is the #1 trigger of daytime fatigue.
148
People who sleep late have more mental stamina and can outperform early risers.
33
"Dysania" is the state of finding it hard getting up out of bed in the morning.
33
Termites work 24 hours per day and they do not sleep.
57