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
The colossal squid has the largest eyes in the world.
4
Only about 2% of the world population has green eyes.
36
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
Sheep, goats, octopuses, and toads have rectangular pupils.
7
Poor eyesight (myopia) is associated with higher IQ.
232
Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
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