The average sperm cell swims at 8 inches per hour.
76
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
-137
The human brain doesn't stop developing until about 25 years old.
102
Your body is creating and killing about 2.4 million red blood cells per second.
17
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Poor eyesight (myopia) is associated with higher IQ.
232