A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15
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
A new parent will lose about 1055.6 hours of sleep in the first year of their child's life - almost 44 days!
6
People who sleep late have more mental stamina and can outperform early risers.
33
The average person falls asleep in seven minutes.
115
Termites work 24 hours per day and they do not sleep.
57
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
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