Probability of spontaneous formation of biological systems

From: Peter Ruest (
Date: Sun Dec 22 2002 - 01:06:43 EST

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    Howard Van Till wrote to Burgy:
    > Here's one suggestion for a possible starting point if you choose to break
    > the silence.
    > Dembski's entire system of arguing for the need for the formational action
    > labeled "intelligent design" (non-natural, non-miraculous, form-conferring
    > action by an unidentified, unembodied, choice-making agent) depends, first
    > and foremost, on successfully demonstrating that some particular biotic
    > system or structure, call it "X", could not possibly have been formed by the
    > joint effect of all actual (whether known or unknown) natural processes. He
    > wishes to have this demonstration seen as a purely scientific enterprise.
    > In his estimation the demonstration of this need is scientifically
    > accomplished by proving that X has the quality labeled "specified
    > complexity." The "complexity" portion of that requirement is satisfied, he
    > says, when it can be demonstrated that the probability for the formation of
    > some X (the bacterial flagellum, for instance) by the joint effect of all
    > actual (both known and unknown) natural processes has a numerical value less
    > than 10 exp (-150). Call this probability P(X|N), where N represents the
    > joint effect of all actual natural processes.
    > Question: Is it possible, on the basis of what is now known about the
    > formational capabilities of the universe, to perform the computation of the
    > actual numerical value of P(X|N) for the E. coli bacterial flagellum?
    > Howard Van Till

    No, it is not, because the bacterial flagellum is much too complex. We
    don't even know of any much simpler system which would allow us to
    perform such a computation.

    At the Conference "Sources of Information Content in DNA" in Tacoma, WA
    (1988), I proposed a computation on a very much simpler system, then
    formulated it again in PSCF, "How has life and its diversity been
    produced", PSCF 44/2 (June 1992), 80-94;, and mentioned it
    occasionally on this list. I hoped to get some constructive feedback as
    to how to proceed in this quest, but no-one ever challenged what I
    wrote, except by question-begging: "we know that evolution occurred and
    that information can arise spontaneously, so what do you want..." etc.
    Perhaps this time some molecular biologist is ready to critically
    analyze my proposal. I quote from my 1992 article:

    "One approach might be to consider the invariant configuration of a set
    of known sequences performing a given function in different organisms.
    Certain sequence positions are observed to be occupied by the same amino
    acids in all known versions of a protein of a given specificity. It is
    then assumed that functionality requires these specific occupations. An
    anologous argument applies to positions permitting a certain restricted
    variability. For good measure, all amino acids chemically similar to the
    ones actually observed at a given position might be added to the set of
    permissible ones (Yockey). The totality of these restricted occupations
    found for a given protein type constitutes its invariant configuration.
    This is a lower-bound estimate for minimal functionality, since
    positional interdependencies and species-specific requirements are
    ignored. It may be compared with an upper-bound estimate of the longest
    feasible non-selected path.

    The result is that reaching a given invariant by a mutational random
    walk within 300 million years is too improbable for three specific amino
    acids already. This estimate, presupposing 3.05 codons per amino acid,
    2.16 mutations per specific amino acid change (geometric average), and a
    mutation rate of 10^-8 per nucleotide replicated, is based on very
    optimistic assumptions: 10^16 moles C per year metabolized in the
    earth's biosphere (today's total biomass production) consisting entirely
    of bacteria (5x10^6 nucleotide pairs and 10^-14 moles C per bacterium),
    and all of this DNA continuously participating in this particular random
    walk. Yet known invariants comprise not 3, but about 30 amino acids for
    basic enzyme functions, such as cytochrome c or ribonuclease, or at
    least 5 amino acids for additional adaptations differing between groups
    of organisms. These requirements are even below the real lower bounds
    for functionality, as they reflect unique occupations only. At present,
    it is unknown whether any smaller invariants might provide some minimal
    functions. The restrictions on functional structures, such as enzymes,
    are such that all mutations we observe today are detrimental or at best
    neutral. To suppose otherwise for earlier organisms is speculative."

    In the meantime, I have become convinced, first of all by biblical
    arguments (already tentatively indicated in my 1992 paper), as well as
    more recently by DNA sequence results indicating conservation of
    insertion points of functionless mobile genetic elements, that evolution
    has indeed occurred. But the fact remains that no one knows how novel
    biological structures/functions can possibly be formed by mutational
    random walks _before_ natural selection of the new function can set in.
    On this list, there has been some discussion of functions emerging in
    the hypothetical RNA world, but none of the fundamentally different,
    primarily protein-based system we know.

    For this reason, I think Dembski's approach (or others of the ID group)
    may perhaps provide some insights into this problem of the emergence of
    new information. I think it will not be possible to compute the
    probability of formation of any complex system. The best we can hope for
    is the estimation of some very very rough upper bounds for such a
    probability. I certainly don't expect any "proof of God" - in fact, I
    think they would be mistaken in attempting such a thing. But the
    _scientific_ question of the emergence of novel biological information
    has been terribly neglected by the origin-of-life and the
    mechanisms-of-evolution communities. Is this the case because it is such
    an intractable problem? And if so, why is it intractable? Would this
    again lead us into theology?

    Wishing you all a blessed Christmas time

    Peter Ruest

    Dr. Peter Ruest, CH-3148 Lanzenhaeusern, Switzerland
    <> - Biochemistry - Creation and evolution
    "..the work which God created to evolve it" (Genesis 2:3)

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