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This Impossible New Color Is So Rare That Only Five People Have Seen It

Source: Scientific American (YouTube)

Have you ever seen the color “olo?” Unless you are one of only five people on the planet who have, the answer is ‘no.’
Recently, researchers achieved the unusual feat of stimulating the eye in such a way as to allow it to see a color outside the range of normal human vision. This work is brand new, but scientists hope that it will lead to new vision treatments and help us to better understand how animals see the world.