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
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34
Bats sleep 18-20 hours per day.
5
You forget 90% of your dreams.
256
The strangers in your dreams are actually people that you've seen in real life.
50
If you hold farts in during the day, they'll just come out when you sleep.
16
Those who get out of bed by 7am are more likely to be thinner and happier.
20