When you are looking at someone you love, your pupils dilate, they do the same when you are looking at someone you hate.
1k
Poor eyesight (myopia) is associated with higher IQ.
232
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
Sheep, goats, octopuses, and toads have rectangular pupils.
7
Tigers can see 6 times better at night than humans.
305
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22