The human brain is more active during sleep than during the day.
28
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
47% of people have a nightmare at least once a month.
186
Termites work 24 hours per day and they do not sleep.
57