Bats sleep 18-20 hours per day.
5
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
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
Dieters who sleep more take off more fat that those who sleep less.
159
Termites work 24 hours per day and they do not sleep.
57
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34