Word: fovea
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Dates: during 1940-1949
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Sharp vision and color vision have two other common denominators. One is a highly sensitive dimplelike spot on the retina (the fovea centralis-literally, "central pit"), which acts as a magnifying device to spread the image over a greater number of visual cells. In this dimple, common to the vertebrates with the highest acuity (some birds have two in each eye), there are no rod cells. The cones are slim and tight-packed. The other common denominator is the mechanism for accommodation-ability to focus the eye, maintain a sharp image of a moving object...
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