Re: [asa] TE/EC Response - ideology according to Terry

David:

1. I think that we are now more or less agreeing on a few points: (1)
Nature is distinct from God; (2) It has regular workings; (3) God only
rarely overrules those regular workings. I think we could have got to this
earlier, but for some dancing-around with theological language which in my
view was unnecessary for dealing with the common-sense point I was making,
but now that we are here, let's be thankful for that.

What I was asking you was whether you thought macroevolutionary change
proceeded, in your view, entirely from the regular workings of nature, and
you have finally said, unless I have misunderstood you again, "Yes". If
your view is different, i.e., if you think that macroevolution does not
proceed entirely from the *regular* workings of nature but requires some
exceptions -- I don't give a hoot whether the exceptions are scientifically
detectable or not -- then you are free to say so now. Otherwise, I will
assume that you believe that macroevolution is as fully natural a process as
embryonic development, lightning bolts, the boiling of water, university
Arts professors voting for Democrats, Conan O'Brien bombing when trying to
be funny, etc.

2. Regarding lungfish, I apologize for not getting your point. My point
was that I was aware that evolutionary theorists have always used modern
lungfish as an example of the sort of creature that could have been
transitional to land life. Your point was that lungfish have both gills and
lungs. Fine, I grant it. Also I grant (I haven't checked, but I have no
reason to doubt you) that fish developed lungs before they developed stumpy
fins. And of course I grant that if first there were fish with lungs and
later those fish developed stumpy fins, they could putter around on the
land.

Of course, your argument does not at all address the question how lungs
arose in the first place. On your premises, there was a time when lungs did
not exist. If you are Dentonian, you might argue that lungs were implicit
in the DNA from the beginning, latent, at least in rough outline, just
waiting for a few key additional mutations and perhaps some biochemical
trigger to be expressed morphologically. But if you are a classical
Darwinian, you will not believe that. Rather, you will have to believe that
there was a time when there were not only no lungs, but also none of the
complex DNA coding for lungs (or for many of the associated systems of the
body necessary to make lungs work). Then you have to explain how lungs
might have arisen via stepwise mutations, selectively useful, and you have
to provide probability calculations that such structures could have arisen
on time, based on the number of mutations needed, the average reproductive
rate and sexual lifespan of female fish, the number of generations available
based on the fossil record, etc. I take it that you have not done this
calculation; I know of no evolutionary biologist who has. And I have never
been able to understand why any scientist would believe such a thing
probable without having done such calculations.

3. Regarding the rest of your points, you have assembled a fine array of
anatomical and genetic evidence which can indeed be plausibly explained by
an historical hypothesis. I don't consider such evidence as "proof",
because there is no strictly logical inference from structural and/or
genetic similarities to a historical process, but I have already indicated
that I am not opposed to the macroevolutionary hypothesis in principle, and
I'm happy to accept it as my tentative explanation.

The interesting question for me, and the question which lies behind the
entire public debate over Darwinism, is whether these transitions were
entirely unguided. If neo-Darwinism has nothing to say on this question,
then neo-Darwinism has nothing very interesting to say. I've already
demonstrated, or at least indicated, that Darwin and all his major early
disciples believed that the transitions were unguided, and that the
unguidedness was central to the theory as they conceived it. If you and
other TEs wish to say that they misconceived his own theory, or that people
shouldn't be interested in debating the theory as they conceived it, you may
do so; but the public will continue to debate it; Dawkins and Coyne will
continue to debate it; YECs and OECs will continue to debate it; ID people
will continue to debate it. In fact, Western civilization has been debating
the general principle of "unguidedness" since the days of Plato and
Lucretius. TEs cannot make the debate go away by waving the magic wand of
methodological naturalism versus metaphysical naturalism. Rational men and
women will always ask whether or not it is plausible that living systems
could originate and evolve via purely Darwinian means, and they will demand
direct answers to that question. If they can't get direct answers from TEs,
they will deem TEs irrelevant and get them from someone else. The TE
strategy of denying the validity of the debate, on the grounds that it is
metaphysical rather that scientific, is a complete non-starter.

Cameron.

----- Original Message -----
From: "David Campbell" <pleuronaia@gmail.com>
To: "ASA" <asa@calvin.edu>
Sent: Wednesday, July 22, 2009 7:58 PM
Subject: Re: [asa] TE/EC Response - ideology according to Terry

>> 1. I'm not downplaying the importance of the primary cause. I am saying
>> that it is not a "local" cause in the sense that static electricity is.
>
> God, being omnipresent, is as local as you can get.
>
>> Alternately, if are thinking of God as "powering" the laws of
>> nature at every moment, a sort of continuous creation, so that God
>> "powers"
>> the lightning bolt locally, I could go for that, too. God is, as it were,
>> within the lightning bolt, within the laws of nature, manifesting his
>> power
>> at all times through particular natural events. This is no problem for
>> me.
>
> "Continuous creation" as a phrase might suggest that God is
> essentially remaking everything every second. I hold that creation is
> firmly distinct from God (i.e., not pantheism, panentheism,
> panninitheism, whatever) and that it is in continuity with what was
> existing before.
>
>> But it sounds very much to me as if you and Terry are saying that in
>> addition to all such ways that God can be construed as acting "locally",
>> he
>> performs some *extra* action of some kind to make *that particular
>> lightning
>> bolt* fall, an action that he does not perform in the case of any other
>> lightning bolt.
>
> No, God is acting locally in every actual lightning bolt, whether it
> obeys the regular laws of nature or it doesn't.
>
>> And I don't see how you can say that without stepping outside of the
>> rigorous naturalism that you and Terry seem to be endorsing.<
>
> My naturalism isn't all that rigorous. What I assert relating to
> methodological naturalism is that a) it works pretty well for the vast
> majority of situations; b) it's about all that science is capable of;
> c) as far as we can tell, it's working with regard to describing
> evolution.
>
>> Neo-Darwinism says that God doesn't have to do anything extra, because
>> nature already has the capacity for macroevolutionary change.
>
> As a biological concept, Neo-Darwinism says that populations change
> over time in certain ways due to certain factors. It doesn't say
> anything about God.
>
> God doesn't have to do anything extra because He's doing everything
> already anyway. (Not to deny our responsibility, etc.) God is
> capable, as far as we can tell, of creating the observed diversity of
> organisms by following the patterns that we recognize as natural laws.
>
>> 2. I've known about lungfish since I was five years old, when I read my
>> first book on dinosaurs (my favourite subject as a child).<
>
> Then why do you repeat the error of claiming that lungs and gills are
> mutually exclusive? Going from gills to lungs is not that hard,
> either-millions of tadpoles make the transition from gills to lungs
> every year.
>
>> You line up a bunch of existing features of animals -- animals with
>> different levels of complexity in their eyes, or animals with gills,
>> gills plus lungs, then just lungs, etc. -- and then you infer from this
>> functional sequence an actual historical process of development. You ask
>> me to imagine a historical process by which the forms shade into each
>> other.<
>
> No. I am a paleontologist doing DNA work in vain hope it will get me
> a job. For the fish-amphibian transition (not to mention many other
> transitions in taxa with good fossil records), we have a series of
> fossils providing detailed evidence on the transition. Many types of
> relatively primitive bony fish have air-breathing, and the swim
> bladder seems to likely derive from such a predecessor. This suggests
> that a lung was present in the common ancestor of regular ray-finned
> fish and lobe-finned fish. The lungfish had lungs and leg bones
> (burrows provide fossil evidence of relying on lungs; most modern
> lungfish have reduced fins); leg bones are evident for the extinct
> fish most closely related to the amphibians and lungs presumably were
> not lost and then re-evolved despite the limited direct fossil
> evidence about lungs. We also have the molecular data indicating that
> lungfish are indeed more similar to tetrapods genetically than to any
> other fish; coelacanths are next most similar genetically. The oldest
> fossil amphibians have traces of continued aquatic life (e.g., lateral
> line, relatively weak limbs), showing that full replacement of side
> fins with legs and feet preceeded significant terrestriality. (Even
> lungfish could probably wiggle across wet ground; tail fins probably
> had not changed much).
>
> Certainly there are organisms with different levels of complexity,
> though it is also true that living organisms all have diverged in some
> ways from their ancestors. "Living fossils" retain certain components
> that were also present in relatively distant ancestors, but not all.
> Ironically, the incorrectness of merely lining up modern things
> underlies a problem of "irreducible complexity"-type arguments-they
> tend to assume that everything has to appear at once in the final
> form. Nevertheless, the fact that organisms do fall readily into such
> evolutionary lineups is good evidence for evolution.
>
>> Of course, I can *imagine* such a process. I can imagine such a process
>> by
>> which a centaur and horse, or centaur and man, are related as well. I
>> could
>> even dream up a "natural selection" explanation of how centaurs could, in
>> certain environments, have a survival advantage over horses (or men, take
>> your pick). But I have absolutely no evidence that the genome of any
>> horselike or anthropoid creature is capable of such a transformation.
>
> You have no evidence that the genome of any horselike or anthropoid is
> incapable of such a transition. The chief difference is the fact that
> we don't have any evidence of centaurs and so have no evidence that
> such a process has taken place, whereas we do have plenty of evidence
> that fish did transition into amphibians.
>
>> Nonetheless, what evidence do I have that the genome is capable of such
>> transformations? Transitional forms such as Tiktaalik give me no clue
>> about the mechanism.<
>
> Actually, they can provide some clues-the paleoenvironment tells us
> something about the selective pressures, as do associated fossils.
> The details of fossil anatomy can be combined with studies on genetic
> controls on the relevant bits of modern organisms to get an idea of
> the exact genetic changes.
>
> Study on the genetic details of development in modern relatives will
> probably be the most productive for tellign you just what genes were
> involved in a particular transition.
>
>> Am I to imagine that chance mutations, without any co-ordination,
>> happened to produce viable intermediate forms?<
>
> This is painting the target around the arrow after it hits. Mutations
> that are as "chance" as anything else produce viable variation. Any
> variation is intermediate. If you are shorter than about 186 cm, I am
> transitional between you and taller people.
>
> The fish-amphibian transition is not a perch suddenly sprouting feet.
> Sarcopterygians developed stalked fins, aka lobe fins, with bones in
> the stalk. Still a fin on the end. Some then develop toes along with
> the fin. Other rearrangements are going on in other parts of the body
> as well.
>
> However, suppose the arthropods had developed lungs rather than
> tracheae and consequently grew big enough on land to keep the basal
> amphibians from getting onto land and being successful there. The
> arthropods might then be researching how one obscure group of fish
> developed some features that helped them do well in shallow, variable
> water settings, but never amounted to more than that. If you look at
> the series from sarcopterygians to amphibians (or reptiles to mammals,
> or any number of other well-documented transitions), no one step is
> all that big. It's only in hindsight that we get excited about the
> changes (and most people only get excited about the changes that lead
> to us).
>
>> Then I need a proposed genetic pathway, or I can't test the assertion.<
>
> The paleontological evidence, as well as the genetic and anatomical
> similarities, etc. point towards the assertion that the change
> occurred. A genetic pathway related to how it occurred. There's all
> sorts of ongoing work in evo/devo, gene function, etc. that help us
> tell what the genes are that affect things such as limb development,
> growing lungs or gills, etc. We don't know their full activity in
> model organisms like fruit flies, nematodes, mice, zebrafish, humans,
> etc., so it's premature to expect full details to be worked out for
> lungfish or coelacanths. However, we do have a good idea of what are
> some of the genes that ought to be looked at to get a better handle on
> this. I don't know if anyone has had success in raising lungfish in
> the lab.
>
>> The difficulty with macroevolutionary theory at this point is that it is
>> still premature. Until we know the workings of the genome and of
>> developmental processes the way a mechanic knows the workings of a car,
>> all
>> proposed genetic pathways are largely guesswork.
>
> No, it depends on for what. We have very good genetic pathways for
> various molecules, because the genetic question then is relatively
> straightforward. For the evolution of a particular feature such as a
> limb, there are many more genes involved and we need to know about
> more of them. However, we do not have to know exactly what all the
> genes invovled are to know something about the most critical issues.
> For example, looking at genes involved in triggering and localizing
> bone growth would provide the most critical information related to
> limb evolution. Other genes are involved in various ways, but that's
> the key question-how do you get leg bones or toes or a shoulder girdle
> or whatever part you are looking at, not the precise determinant for
> the number of toes or configuration of the ankle bones.
>
>> If evolutionary biologists want to play a guessing game -- may have,
>> coulda, mighta (note that the
>> conclusion of the article Preston Garrison cited is filled with
>> subjunctives) -- that's their own in-house academic business, but they
>> shouldn't leave the public with the impression that they know how
>> evolution works, when they are almost completely in the dark about how it
>> works when it comes to the hard-nosed details.<
>
> We do know much about the evolutionary sequences for any group with a
> good fossil record that is well-studied evolutionarily. (Many
> microfossils have only been studied to name them and assign them to
> ages to help tell if your well is at the right depth for oil or other
> drilling question.) Molecular data give us a fairly good picture of
> general relationships of organisms, though there are a lot of details
> to fill in.
>
> We also know a lot about the mechanisms. We know about how DNA works,
> how natural selection works, other factors than influence evolution,
> etc.
>
> What we don't have is the full details of exactly how everything
> happened. In part, that would require a time machine. However, we
> are gradually getting an increasingly better picture of how it
> happened. We are not running into any walls that would point to a
> need for miracles in the process.
>
>> By the way, since you've said the mutations aren't simultaneous, what is
>> the
>> current Darwinian narrative explaining how being able to walk on crude
>> foot-fins would give a selective advantage, if the fish couldn't breathe
>> out
>> of water yet?
>
> Once again, you forgot the lungfish. They could breathe out of water
> before they had feet, and probably before they even had any equivalent
> of legs.
>
> The first amphibians with reasonably good legs seem to have still been
> essentially aquatic, though presumably they could cross a mudflat.
> Presumably the legs functioned mostly for walking on the bottom of the
> water or crawling through debris (logs, roots, etc.). Fast swimming
> is not the only way to go in the water.
>
>> (Let me guess: tidal pools on the ocean shore, where fish
>> with gills and legs could perhaps survive for a few seconds out of the
>> water, snatch some snails and worms from the mud, and quickly waddle back
>> to
>> a deeper stretch of water to plunge under for some air?)
>
> Have you ever been fishing? Fish do not die in a few seconds of
> coming out of the water (not counting a predator). If it's humid,
> they can survive quite a while. Several fish with no lungs tend to
> cross land on wet nights (e.g., eels, walking catfish; grunions are
> somewhat in this category). I don't recall just what mudskippers do
> to breathe air, but they spend much of their time out of the water.
> (It was rather odd in Fiji seeing something skim across the surface of
> the water and climb out on a rock and then realize it was a fish.)
>
>> Or perhaps you are insisting that the fish already had lungs, in addition
>> to their gills,
>> before they developed the feet? In that case, remind me how, in the
>> absence
>> of surviving soft tissues, palaeontologists can be certain that fish with
>> both lungs and gills existed, before feet (or lobe-fins) were developed?
>
> Yes, I am insisting that. Lungfish again are a big part of the
> answer. The lung plus gill condition is evidently the state for the
> common ancestor of lungfish and amphibians. Many primitive ray-finned
> fishes essentially have lungs of some sort, so lungs probably were a
> significant supplemental source of oxygen long before anything got
> close to becoming an amphibian. Even now, tarpons will drown unless
> they can get air, and they're a reasonably standard ocean fish.
>
> Gills are associated with particular bones, though fairly standard in
> any fully aquatic amphibian.
>
> Additionally, amphibians can breather through their skin and mouth
> lining. A large chunk of amphibian species have neither lungs nor
> gills as adults.
>
>> And even if fish did have both lungs and gills before developing
>> lobe-fins,
>> what *Darwinian* reason can be given for the simultaneous existence of
>> lungs
>> and gills -- two different and redundant oxygenation systems? That uses a
>> lot of bodily resources for a something that isn't needed -- fish don't
>> need
>> lungs.
>
> Many do-as noted above, some modern fish can drown if they don;t
> breathe air. Lungs let you get air, very rich in oxygen. Gills let
> you breathe underwater, but it's a lot poorer in oxygen. Lungs also
> provide buoyancy.
>
>> The simultaneous existence of lungs and gills makes much more sense
>> on Dentonian than Darwinian lines. If Denton is right, the lungs may have
>> evolved before they were put to use because the genome, as it were,
>> "thinks
>> ahead". So once again, design comes out on top and neo-Darwinism comes
>> out
>> on the bottom.
>
> But why did it think ahead in assorted fish, only one of which
> actually went to amphibians? The pattern is not that of thinking
> ahead, it's a pattern of making use of what's handy, as far as the
> biological aspects go.
>
>
> --
> Dr. David Campbell
> 425 Scientific Collections
> University of Alabama
> "I think of my happy condition, surrounded by acres of clams"
>
>
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Received on Thu Jul 23 03:33:30 2009