Re: Critique of ID & No Free Lunch

From: Terry M. Gray (grayt@lamar.colostate.edu)
Date: Thu Sep 12 2002 - 21:50:26 EDT

  • Next message: Tim Ikeda: "Re: Critique of ID & No Free Lunch"

    Josh wrote:

    > If we can establish that
    >the current structure that exists today could not have evolved for some
    >reason, we need not worry about evidence for its evolution. ... In
    >the end, if they
    >hypothetically proved beyond doubt that the flagella could not evolve, then
    >the evidence you want has never existed for the flagella and your
    >considerations are a diversion.

    This points out my fundamental beef with the ID folks as it concerns
    biology and possibly pre-biotic evolution. There are confident
    assertions based on all too uncertain probability calculations that
    "flagella could not evolve" (and thus allowing the dismissal of the
    various circumstantial evidences suggesting that they did). Believe
    it or not, I'm open to ID, i.e. we may very well hit a brick wall
    with respect to possible evolutionary explanations. I just don't see
    that we're anywhere close to being able to say that. In my opinion we
    have to know a lot more than we do in order to say that such and such
    couldn't have happened.

    I've pointed out earlier that most of the genome research is oriented
    toward medicine and agriculture: comparative mammalian genomics,
    comparative bacteriological genomics, and comparative plant genomics.
    The fundamental cell biology features of mammal and plants are
    basically the same and so the comparative work there doesn't tell us
    beans about the origin of various primitive eukaryotic features. I'm
    not sure that comparing various modern strains of bacteria is going
    to get too far either. Basically, I'm saying the same thing that Tim
    said. Comparative genomics of various protists will get us somewhere,
    I think, as will comparative genomics of archaea. At the same time,
    I'm not afraid to say that the evidence may be gone--that a lot of
    the formative cell biology structures came into being prior to the
    rise of "modern" genomes. I don't say this just to give an "it must
    have evolved" answer, but the reality is that we may not be able to
    find the answer in modern organisms.

    This is why I went to the evolution of cooperative binding of oxygen
    in hemoglobin when I first encountered Behe's arguments. I wanted to
    show that an irreducibly complex structure/function like hemoglobin
    could evolve. (Now if you're going to say, as Mike does, that if it
    evolved then it apparently wasn't irreducibly complex, then you're
    just being tautological.) Hemoglobin is irreducibly complex because
    the function is a function of the whole (kind of like a
    mousetrap)--there is no cooperative binding of oxygen without the
    whole (at least the alpha-beta dimer). Oxygen binding is not the
    function of hemoglobin--cooperative oxygen binding is. This is an
    example of a recently obtained function, i.e. cooperative oxygen
    binding. But a reasonably plausible account can be given as to how
    non-cooperative oxygen binding to simple cooperative oxygen binding
    to full hemoglobin like oxygen binding came into being. When we know
    as much comparative stuff about flagella as we do about hemoglobin,
    I'll begin to listen to some of these ID arguments (if the lack of an
    evolutonary account is not forthcoming given that evidence).
    Otherwise, we're just looking at pulsars and calling them "little
    green men" because we don't know of anything that could "naturally"
    create that pattern.

    TG

    -- 
    _________________
    Terry M. Gray, Ph.D., Computer Support Scientist
    Chemistry Department, Colorado State University
    Fort Collins, Colorado  80523
    grayt@lamar.colostate.edu  http://www.chm.colostate.edu/~grayt/
    phone: 970-491-7003 fax: 970-491-1801
    


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