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
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
Cows can sleep standing up, but they can only dream lying down.
745
The strangers in your dreams are actually people that you've seen in real life.
50
Dieters who sleep more take off more fat that those who sleep less.
159
Honeybees never sleep.
276
The higher someone’s I.Q. the more likely they are to be sleep deprived.
29
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15