The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
21
If the human eye was a digital camera, it would have 576 megapixels.
25
Poor eyesight (myopia) is associated with higher IQ.
232
The colossal squid has the largest eyes in the world.
4
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
Tigers can see 6 times better at night than humans.
305
Sheep, goats, octopuses, and toads have rectangular pupils.
7