The average sperm cell swims at 8 inches per hour.
76
Yawns are more contagious among people with closer relationships.
163
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The average person's skin weighs twice as much as their brain.
131
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
-137
When you take a step, you are using up to 200 muscles.
886