Re: Don't forget about me! (distal vs. proximate)

From: Tim Ikeda (tikeda@sprintmail.com)
Date: Sat Apr 21 2001 - 10:46:12 EDT

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    Rob wrote:
    >In a message dated 4/20/01 8:36:14 AM, tikeda@sprintmail.com writes:
    ><< But I thought ID was a scientific, and not a theological theory.
    >ID may have theological implications but according to all the
    >bulletins issued by the Discovery Institute and all its "star"
    >writers, its first and foremost driver is observation and
    >science. >>
    >
    >Tim:
    >
    >I used the Genesis account to illustrate the idea that design precedes
    >application in the biological world. Here is a scientific illustration:
    >
    >"I am in agreement with Mr. Gross when he refers to "new and
    > astonishing evidence" about the origin of the eye. Herewith the
    > facts. Halder, Callaerts, and Gehring's research group in
    > Switzerland discovered that the ey gene in Drosophila is virtually
    > identical to the genes controlling the development of the eye in
    > mice and men. The doctrine of convergent evolution, long a
    > Darwinian staple, may now be observed receding into the darkness.
    > The same group's more recent paper, "Induction of Ectopic Eyes by
    > Targeted Expression of the Eyeless Gene in Drosophila" (Science
    > 267, 1988) is among the most remarkable in the history of biology,
    > demonstrating as it does that the ey gene is related closely to the
    > equivalent eye gene in Sea squirts (Ascidians), Cephalopods, and
    > Nemerteans. This strongly suggests (the inference is almost
    > irresistible) that ey function is universal (universal!) among
    > multicellular organisms, the basic design of the eye having been
    > their common property for over a half-billion years. The ey gene
    > clearly is a master control mechanism, one capable of giving general
    > instructions to very different organisms. No one in possession of
    > these facts can imagine that they support the Darwinian theory.
    > How could the mechanism of random variation and natural
    > selection have produced an instrument capable of anticipating the
    > course of morphological development and controlling its expression
    > in widely different organisms?" (Berlinski D., "Denying Darwin:
    > David Berlinski and Critics", Commentary, September 1996,
    > pp28,30.
    >
    >I suggest that the ey gene is a design gene that precedes and is used
    >by many organisms in an evolutionary manner. What is the origin of
    >this gene?

    Ah Berlinski. I've seen that before.
    There are two points to your letter:
    1) To provide explanation of why one may suppose the an active
       designer has become dormant.

    2) While were at it, to present cases that supposedly defy
       evolutionary explanations.

    I'll talk about #2 first (for now) but I'd really like to stick
    to #1 in future exchanges, in hopes of reaching consensus on the
    first point.

    Initially, I'd suggest going to Google and looking up "Pax-6".
    Better yet, Medline. Here's some information one can find.

    In eye spot development, Pax-6 expression correlates with the
    initial differentiation of developing cells in the region where
    eye spots will form. Experimental work suggests that Pax-6
    is one of the upstream initiators/regulators for subsequent
    development of species-specific eye structures but that it does
    not determine what structure of eye will form. Regulation of
    further differentiation can fall to downstream control
    elements.

    Pax-6 is a transcriptional factor found in all phyla that have
    neural systems and eyes. It has multiple roles associated with
    brain and eye system development. This developmental gene belongs
    to a larger family of related transcriptional factors that are found
    in most, if not all metazoans, which indicates that these genes arose
    prior to the diversification of organisms with neural structures
    and certainly before those with eye-spots.

    Pax-6's exact evolutionary origin is currently unknown, except that
    it clearly arose from a class of transcriptional factors which have
    many roles in other parts of cell regulation and gene expression in
    the metazoans. I would not be terribly surprised if Pax homologs
    are common to most eukaryotes. Current thinking is that Pax-6
    represents a sub-class of Pax proteins which at one point became
    locked into eye-spot differentiation. I don't know if Pax-6's
    association with other neural developmental pathways preceded or
    post-dated its association with eye-spots.

    >And this:
    >
    >The anti-Dawkinsian ex-Cambridge geneticis Gabriel Dover thinks that
    >*all* genes will turn out to be modules of master genes like the
    >Pax-6 gene:
    >
    > "I'm sure that when the full glory of all the genes in all the modular
    > 'packages' of development and behaviour are exposed, no large
    > numbers of species-unique or package-unique genes will be found.
    > Instead, differences in the modular construction of organisms will
    > be the result of specific permutations of universally shared modules.
    > For example, some of the genes that are known to interact with Pax
    > 6 in Drosophila, such as twin of eyeless, sine oculis, eyes absent,
    > dachshund, eyegone and teashirt, are involved in the development
    > of the sex gonads, legs and embryo segments. And there is no
    > simple linear pathway for eye development starting with Pax-6. As
    > with the genes influencing embryo development that I described
    > previously, there is a complex network of interactions involving
    > multifunctional genes regulating each others' activities via versatile,
    > modular and compound promoters." (Dover G.A., "Dear Mr
    > Darwin," 2000, p.172)
    >
    >I take these to indicate that design precedes application and is used
    >by many different applications. I don't see straightforward natural
    >seloection in it.
    >
    >Comment?

    Ummm... I agree with the quoted paragraph of Dover. Many have expected
    that for years and I don't see any paradigm-shattering concepts there.
    Sounds like an evolutionary explanation to me. To paraphrase and analyze
    your comments:

    "Design (origin) precedes application...
    "...and similar structures are used in different applications."

    Natural selection doesn't operate on things that "will be", only on
    things that "are there right now". With the idea of common descent,
    it is assumed that new genes arise from modification of earlier ones.
    Why would the emergence and swapping of modules be unexpected? Heck,
    in the lab we've even confirmed the swapping of modules for individual
    genes, protein subunits, and developmental pathways.

    Now, back to the original point of the discussion: Why would a
    design theorist presume that a designer's creative acts are finished?
    I would agree that if we used our current understanding of biology and
    organismal history, we might suspect that if a designer existed,
    we'd expect to find few instances of direct, extra-natural biological
    assembly [Personally, I wouldn't be surprised if those instances
    numbered close to zero]. The number of instances would be proportional
    to the number of "gaps" that would be impossible to bridge with natural
    mechanisms. And clearly, there is a diversity of opinion among ID'ers
    about how frequently these gaps occurred. Some, such as yourself, seem
    to think that gaps align at least with phylum-level transitions. Others
    think gaps occur roughly at the family-level, suggesting more frequent
    events. And some think the human/ape split is too great for evolution,
    which suggests very frequent design events.

    Nonetheless, these thoughts give no reason to suppose that a
    designer's work is finished on Earth. Why whould one expect that
    no additional species, families or phyla are slated for future
    creation? How do we know there are no further designs waiting to
    be applied?

    Regards,
    Tim Ikeda
    tikeda@sprintmail.com



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