1. People reportedly prefer blue toothbrushes over red ones.

2. Some people used to believe that kissing a donkey could relieve a toothache.

3. Scientists say that the best time to take a nap is between 1 pm and 2:30 pm. because that's when a dip in body temperature makes us feel sleepy.

4. Because the speed of the Earth's rotation changes over time, a day in the age of dinosaurs was just 23 hours long.

5. Hummingbirds' wings can beat 200 times a second.