What I don't understand is the mechanics of how it gets there. In other words, how would a lens form? A layer of cells over an area of light sensitive cells offers absolutely no advantage in seeing light better until it evolves translucentness, a definate shape, and supporting fluid or structure to keep the lense the right distance away from cells.
Ok, so we got a critt with a sensitive light sensor and it has a thin layer of protective tissue over it. This is generation A which leads to generation B1 and B2. B1, has varied slightly so that the thin layer of cells has become pigmented makeing it harder for the light spot to detect light. B2 has a variation that has the skin become more transucent, by having less pigment and thinner tissue.
B1 gets eaten more, B2 gets eaten less on the bassis of sight alone. Eventually B1 gets eaten to the point of extinxion, but B2 is alive and well cuz it can actually see its predators.
A few generations later, say generation D1, the skin has not only become more resiliant, but has developed a thin layer of fluid between it and the eye, mainly because the old layer of thin skin didnt offer as much protection and could be wounded easely. So a protective layer of fluid formed, since we already know from B1 that dark skin dosn't work over the eye, the thiker skin evolved so that it would be see-thrugh.
And so on and so on, over millions of years.
An arperture is also extremely complex, and I cannot imagine any way it could evolve in small steps.
Its not that complex, have you ever seen a pinhole camera? It's basicaly a hole in a box, you can vary the hole size to create an aperture. Very simple, infact some animals have eyes like this. Like the Nautillus.
Unless there is some specific evidence to show how this happens, perhaps you all might understand my viewpoint better when I say it takes a little imagination to get it to work.
Evolution: Library: Evolution of the Eye
Its got a video and everything. Its pretty cool.
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