Re: Johnson, Darwin, and transitionals

From: Chris Cogan (
Date: Mon Jan 24 2000 - 23:06:11 EST

  • Next message: Stephen E. Jones: "Re: Scientist disputes fossil is 'missing link' between dinosaurs, birds etc"

    > >Chris
    > >I said in my original post on the topic:
    > >"To determine whether Johnson had any valid point at all
    > >would require determination of details that he does not seem concerned to
    > >bother with."
    > Yes, in a thread you entitled "Johnson Blows It Again," you sandwiched
    > this point between the claims, " Evolution proceeds much more slowly
    > in stable environments," and " Evolution is *definitely* not to be
    > as always proceeding at a constant rate." It took this to mean that
    > Johnson blew it by ignoring this detail.
    > >I gave an explanation that would be expected to hold *if* certain
    > >held. I did not claim that those conditions *did* hold.
    > It looks to me like you were:
    > " Since the *main* function of selection is actually the restriction or
    > *prevention* of evolution, it is not hard to understand that, in a stable,
    > steady, undersea environment, once organisms got locally optimized for
    > niche in the environment, nearly *any* genetic variation would be culled
    > out."

    This looks straightforward enough to me.

    > Remember, that this was all part of a reply to something Johnson
    > wrote.

    In which he lied and claimed that, in effect, the undersea environment *was*
    stable (the only *possible* condition under which no evolution would occur)?

    > >What I was pointing
    > >out was that the fact of little or no discernible evolution over a period
    > >time *by itself* would not refute evolutionary theory. Hence the "Not
    > >necessarily* with which I began my comments. My explanation assumed
    > >hypothetically the situation where there is very little environmental
    > >*and* organisms are optimized for their current niches. Perhaps Mike
    > >this part of my remarks.
    > Perhaps I was thrown off balance by the *title* of your thread. It looks
    > clear to me that you were trying to refute Johnson's claim by noting
    > that contrary to his claim, "a stable, steady, undersea environment,"
    > would be "exactly the environments in which we would *not*
    > expect to see the most evidence for evolution." You didn't
    > title your thread, 'Johnson could be blowing it,' now did you?

    See above. He *STILL* blew it, no matter which way we take his remarks. If
    it is *true* that there was no evolution, then it *requires* that the
    environment be stable and that the organisms be locally optimized (if
    evolution is impossible, then significantly unsteady environments will
    simply kill many of them off). But, if it's true that significant evolution
    *did* occur during the times in question, why is Johnson telling us that it
    *didn't*? Either way, Johnson blew it.

    I don't happen to have much knowledge of the period in question, so I, being
    an utter fool, took the demagogue at his word. If you want to bitch at
    someone for having a "plastic" theory, go talk to Johnson, whose theory is
    so plastic that reality and logic simply make no difference to him.

    > I have no desire to quibble further, so I'll simply leave it to
    > each reader to decide for themselves.
    > >If the organisms were significantly *non-*optimized for their
    > >we would see relocation, extinction, or evolutionary change, even in an
    > >unchanging environment.
    > >And, if the environment is *not* stable, then we should expect
    > >change.
    > >Only in the case where optimization is "complete" (within the reach of
    > >genetic changes) *and* the environment puts selective pressure on
    > >to *stay* as they are, *will* they stay the way they are.
    > >In fact, if it turned out that the period in question showed no
    > >development *and* it was known that environmental changes were fairly
    > >continuous, severe, and long-lasting (i.e., lasting long enough to put
    > >selective "pressure" on organisms that should result in significant
    > >*THEN* we could say that something was wrong with evolutionary theory.
    > This sounds good, but let's take a closer look.
    > 1. What do you mean by "evolutionary development?"
    > 2. How are we to know if the environmental changes were continuous,
    > severe, and long-lasting?

    One way we can tell is by geological examination of sediments, etc. These
    will give evidence of local conditions over time. If exactly the same
    minerals and other indicators are settling out at the same rate (and in the
    same ratios) for a long period of time, it's a good indicator that the
    environment was not changing much. Another indicator is the fossils
    themselves, which will at least indicate whether the organisms in the area
    were optimized for their environments or not (if they are evolving fairly
    continuously and rapidly, they are *not* optimum because they are still
    responding to selective pressures).
    > 3. How do we define 'severe?' How long is "long'lasting?"

    Severe: Strong enough to differentially select variants that would
    previously have been culled out.

    Long lasting: Long enough for evolution to take place (a single disturbance
    lasting but a few hours and then never recurring for millions of years
    obviously does not qualify). For some bacteria, "long lasting" might only be
    a few years. But, since, I assume, we are talking about organisms that leave
    larger fossils, such periods would, I'd guess, have to be at least hundreds
    of years.
    > 4. What distinguishes significant change from non-significant change?

    Whether it imposes selective pressure or not. A change of water temperature
    of 1 thousandth of a degree (on average) for a period of years would not
    normally be significant (though, theoretically, I suppose some organism
    could be right on the verge of blooming or dying out, and even such a small
    change could be significant if it's biochemistry just *happened* to be tuned
    to such precision that such a change triggered biological processes that
    would not otherwise occur).

    > Unless we can nail down these questions, there seems no hope
    > of detecting if something is wrong with "evolutionary theory."

    Yes and no. Obviously, more precision is better. But, the fact that we can
    infer that *no* evolution over a long period of time implies that the
    environment is much more steady than would be implied by *lots* of evolution
    over the same period (given the same initial conditions) is valuable in
    itself. At least we can claim that there *is* a relationship of this type
    between organisms and their environments. Designer theory offers nothing
    even *remotely* comparable.
    > >Moral of the story?
    > >1. Evolutionary theory is more complex in the working out of its
    > >implications than Mike is willing to acknowledge.
    > What makes you think I am unwilling to acknowledge this?
    > That's a might strong claim to attribute to me.

    What made me think that was that you tried to turn my use of evolutionary
    theory for "predictive" purposes into a *failure* of the theory, into a
    symptom of "plasticity," etc., without realizing that such conditions would
    be implied by evolutionary theory if Johnson's claim had been true, thus
    showing not the *failure* of the theory but it's cognitive power to work
    backwards from the occurrence or non-occurrence of evolution to conclusions
    about the environment. Obviously, if it were as plastic as you suggest, this
    would not be meaningfully possible.
    > >2. Try not to too closely emulate Stephen's tendency to misrepresent your
    > >opponent's views by ignoring context and qualifiers.
    > I was certainly not trying to misrepresent you. Maybe you should
    > be more careful and make sure your thread titles don't misrepresent
    > the points you are making.
    > >3. Evolutionary theory is not as "plastic" as Mike would have us believe.
    > If you are going to preach against being misrepresented, may I point
    > out that I said nothing about "evolutionary theory?" I was speaking
    > of the Darwinian interpretation of evolution. Evolution deals with
    > common descent and darwinism deals with the proposed mechanism.
    > Your response to Johnson focused on the mechanism. And I think
    > you've shown just how plastic it can be.

    You may have shown how plastic the terminology may be, but that's all. I
    don't like to use the term "Darwinism" much at all, precisely because it has
    so many meanings, ranging from Darwin's original views to what seem to me to
    be views essentially *compatible* with Darwin's actual views, but going
    rather far beyond them. Johnson, in fact, seems to *deliberately* play on
    this ambiguity (in "Darwin on Trial") sometimes pretending only to refute
    *Darwin's* views, and sometimes implying that he has refuted purely
    naturalistic evolutionary theory *in general*.

    I took you to mean what I have taken to calling NET or Naturalistic
    Evolutionary Theory: The view that evolution occurs by *some* purely
    naturalistic mechanism(s) of variation combined with natural selection or
    cumulative culling by virtue of organisms' relationships with their

    > >It is *certainly* vastly less "plastic" in this respect than designer
    > >which can "explain" not only what *does* or *can* happen under
    > >theory, but what *can't* happen under evolutionary theory, with no
    > >limitations *whatsoever*! Supporters of designer theory are *hardly* the
    > >ones to be talking about the "plasticity" of evolutionary theory, a
    > >in which there are no *conceivable* empirical observations that could
    > >falsify it, because it imposes no restrictions *at all* on what the
    > >empirical facts must be if it is to be true.
    > What "designer theory" am I supposed to be a supporter of? Personally,
    > I think the concept of intelligent design can be used in a way that is
    > far less plastic than the way darwinian interpretations have been used.
    > But that's another topic, as even if your claims are true, the inherent
    > plasticity of darwinism shouldn't be ignored. It's like a politician
    > using illegal campaign donations who responds by accusing the other
    > party of doing likewise (or even worse!).

    See my remarks above. You are confusing strict inference from theory and
    Johnson's alleged fact with plasticity.

    But, also, since scientific theories are never proved by the kind of
    deductivity that characterizes conclusions in mathematics or much of
    philosophy, we frequently have to choose theories to go with based on such
    issues as "plasticity," the richness and solidity of empirical implications
    that can be used for testing, compatibility and complementarity with
    knowledge in other sciences, etc. Evolutionary theory is more "plastic"
    than, say, Newtonian physics, but it is vastly less "plastic" than
    alternative theories that are known and have not already been empirically
    refuted. An example is *any* version of designer theory that *is* truly
    designer theory (of course, "designer" theory can be made to have the same
    degree of strictness that NET has by sneaking NET into it to provide the
    sole mechanism by means of which a Deistic type of designer could "design"
    life, but this simply makes the designer himself essentially irrelevant to
    the theory).

    If you think designer theory can be made so good, why haven't we seen *any*
    examples of *any* of the types of inference I made with respect to Johnson's
    alleged fact? If *no* discernible change over a geologic period of time
    occurs, despite a good fossil record, can we *use* designer theory to
    determine anything about the environment and the relationship of the
    organisms to that environment?


    Why not?

    Simple: *Regardless* of what happens, the designer did it. Any further
    explanation is either reading the mind of the designer or is not designer
    theory. Since we don't have an empirical theory of the designer's mind and
    plans for the future (or the past), there are *no* predictive implications
    to be drawn from the positing of a designer.

    And yet, such implications are absolutely *necessary* to avoiding
    "plasticity." So, if you think you can make it even *slightly* less plastic
    than NET, as you seem to think it can, why have *NONE* of all the dedicated
    ID theory people come up with even the *beginnings* of such a theory.
    Remember, designer theory has been around for nearly two hundred years, at
    least (since Paley's famous watch argument). Further, it has had far more
    believers and supporters than has evolutionary theory. Why then, has there
    been *no* progress toward the development of a viable *non-*plastic ID
    theory? Why is it that we can derive no more empirically testable
    implications from designer theory now than we could in 1802?

    Can we *use* designer theory in *any* scientifically meaningful way, despite
    the fact that it's far older than Darwin's theory or any NET derived from


    Why not?

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