M.J.Thomas Wrote:
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> In the article provided by Bernard as the start to
> this thread I read, “But, once in a great while, a
> random mutation in the DNA that makes up an
> organism’s genes slightly improves the function of
> some organ and thus the survival of the organism.
> In a species whose eye amounts to nothing more
> than a primitive patch of light-sensitive cells, a
> mutation that causes this patch to fold into a cup
> shape might have a survival advantage. While the
> old type of organism can tell only if the lights
> are on, the new type can detect the direction of
> any source of light or shadow. Since shadows
> sometimes mean predators, that can be valuable
> information. The new, improved type of organism
> will, therefore, be more common in the next
> generation. That’s natural selection.
>
> My concern here is the sentence, “In a species
> whose eye amounts to nothing more than a primitive
> patch of light-sensitive cells, a mutation that
> causes this patch to fold into a cup shape might
> have a survival advantage.”
> Three questions.

You need to read Richard Dawkins 1996 Climbing Mount Improbable pp. 138-197 where he gos into excruciating detail precisely on the development of the eye.

> Is there any evidence that this did happen?

yes. There are organisms that have this. Dawkins p. 148-- cup eyes exist in limpets, britleworms, clams, and flatworms.

> Are there other explanations of this type as to
> how the eye (such as found in us humans) evolved
> from "a primitive patch of light-sensitive
> cells"?
yes. Darwin's book 100 years ago provided a pathway by which this could be done.

> Is any explanation of this type scientifically
> provable?
yes. Read Dawkins and see for yourself how much scientific evidence there is . For a quick view look at evolution of the eye in talkorigins.org

Bernard
>
> MJT
>