Sea otters hold hands while sleeping so they don’t drift away from each other.
104
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
Sleeping on the job is acceptable in Japan. It is viewed as exhaustion from working hard. Some people fake it to look committed to their job.
57
Some people have a "natural alarm clock" allowing them to wake up when they want. This is actually caused by a burst of the stress hormone adrenocorticotropin.
15