National Geographic Takes a Close Look at the Evolution of Eyes
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“If you ask people what animal eyes are used for, they’ll say: same thing as human eyes. But that’s not true. It’s not true at all,” said Dan-Eric Nilsson in National Geographic's "Inside the Eye: Nature's Most Exquisite Creation." The story explores the anatomy and evolution of eyes in various species around the world. Pictured here is the eye of the red-eyed tree frog (Agalychnis callidryas).