Years ago I came across an article proposing that the eye first originated as a photosensitive cell in the mass of the brain. At first the cell was binary, it d

Years ago I came across an article proposing that the eye first originated as a photosensitive cell in the mass of the brain. At first the cell was binary, it detected light or darkness, and its function had some positive role in the survival of the organism that possessed it. As time passed the cell became specialized and was relocated closer to the skin. Light penetrates skin, tendon, and bone, albeit in ever smaller amounts. It is not impossible that the brain reacts to light.