A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
You can reschedule your sleeping pattern by not eating 12-16 hours before you want to be awake. Upon eating after this time period, your internal clock will reset to a new day, with the time of your first meal being interpreted as "morning".
11
47% of people have a nightmare at least once a month.
186
44% of kids watch television before they go to sleep.
106
You forget 90% of your dreams.
256