Darwin and the eye

From: John Clark (jonkc@worldnet.att.net)
Date: Sun Jan 14 2001 - 13:51:38 MST

On 12/01/01 John Marlow wrote:

>Darwin himself conceded his theory had fatal flaws the eye, for example;
>too complex, too soon

If Darwin thought his theory had "fatal flaws" he wouldn't have published his book.
Of course he never said he knew all there was to know on the subject and the
complexity of the eye did worry him because he figured 5% of an eye is useless.
However modern scientists have figured out how it must have evolved.

Many simple animals have spots on their bodies that contain pigments that are
sensitive to light, they have zero resolution but they can tell day from night and
that's an advantage over a creature that can't. If the spot is in a shallow
depression in the animal's body it will have more sensitivity in one direction than
another, it will have a little bit of resolution, and that's another advantage over a
creature without that ability. The deeper the depression the better the resolution,
eventually you have a pin hole camera with excellent resolution but with terrible
sensitivity, you need a lens. A drop of water can act like a lens, much better than
a pin hole, and many animals have small glands that excrete moisture on the outside
of their skin. If there were certain proteins in the water it could turn the water into a
colorless jelly and give it some strength, now the lens can become larger. If an animal
evolves additional muscles in that part of its body then it can quickly look at different
things without moving the entire body, a big advantage over a creature who can't.
And now you have an eyeball.

    John K Clark jonkc@att.net

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