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
If you hold farts in during the day, they'll just come out when you sleep.
16
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
Termites work 24 hours per day and they do not sleep.
57
People who sleep late have more mental stamina and can outperform early risers.
33
You burn more calories sleeping than you do watching television.
348
Lack of water is the #1 trigger of daytime fatigue.
148