Last one I promise.

In part two I said photoreceptors are the least important part of the visual system. I said this become in my first thread about the eye, many people gave themselves high-fives after telling me how the eye evolved by using photoreceptors and light-sensitive proteins.

I've attached an image. Look at it closely. Its a simplified illustration of the retina. Notice that its not simple at all. You phave the photoreceptors, bipolar cells, amacrine cells, horizontal cells, and ganglion cells. Each of which has a number of subcategories. These cells inhibit each other, excite each other, and exchange information. In fact, the most important cells are the ganglion cells, they are responsible for edge detection, and making sense of all the incoming information.

If anyone wants to try explaining how they all evolved, and how functionality is possible in their absence. Feel free to do so.