There are about 1,400 different species of bacteria in your belly button.
10
If you are cold you are more likely to be hungry because you use energy to keep warm.
144
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
All humans have the ability to see ultraviolet light, but it is passively filtered out by the eye's lens. People who undergo surgery to remove the lens can detect ultraviolet light.
22
The human brain doesn't stop developing until about 25 years old.
102
The average sperm cell swims at 8 inches per hour.
76
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515