Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
Tigers can see 6 times better at night than humans.
305
Poor eyesight (myopia) is associated with higher IQ.
232
In ancient Egypt, priests plucked EVERY hair from their bodies, including their eyebrows and eyelashes.
130
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.
21
The colossal squid has the largest eyes in the world.
4
There's a woman named Veronica Seider who had vision 20x better than average. She could identify people more than a mile (1.6km) away.
22