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
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
The average person falls asleep in seven minutes.
115
Cows can sleep standing up, but they can only dream lying down.
745
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