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Why did humans evolve to blink?
To approach a question 400 million years in the making, researchers turned to mudskippers, blinking fish that live partially out of water.
A magnified view of the human eye shows the pupil, the surrounding iris, and capillaries on the surface of the eyeball. It's long been known that people blink to keep their eyes moist and protected, but less known is how we evolved the phenomenon. A new study on an amphibious fish called a mudskipper offers clues.
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