Graham,

I understand. I understand that "chose" is not the accurate word.

What I'm saying is that what it comes down to is that, upon asking, "well, just how did eyes evolve from nothing to these marvels that see black and white and color, focus, can cross or, in the case of Marty Feldman, can diverge?", The dismissive answer that is, itself, ignoring the immensity of becoming more complex, and the odds involved, is always something like...

"Photosensitivity is a characteristic that many cells have"

...an answer that acknowledges the "what" in order to minimize the immensity of the question "how?", which is answered quite simply, but emotionally unsatisfactorily, with...

"It mutated that way."

But I understand. Hard to believe that I understand and am as yet, not completely satisfied. But there you have it. I understand.