For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Early American humans hunted car-size armadillos and used their shells for houses.
12
A third of the human population sneezes when they look at the Sun. Light can signal the ocular nerve near the sinuses and triggers a sneeze.
18
If Earth's life was compressed into 1 year, then humans would have been around for only 2 seconds.
15
Tigers can see 6 times better at night than humans.
305
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
In 30 minutes, the average body gives off enough heat (combined) to bring a half gallon of water to boil.
198