Does Michael Denton understand current evolutionary theory?

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This is based on a discussion started in another thread. Consider the observation documented in the figure below:

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Let’s compare two attempts to explain this observation: The standard current evolutionary account, and that suggested by Intelligent Design proponent Michael Denton.

According to evolutionary theory, the homologous structures depicted above are evidence of common descent, and are accounted for by it. All forelimbs are derived from a common ancestor whose forelimbs showed the basic structure in common between the four examples above, and the differences between the examples are accounted for by subsequent alterations, thru mutations, in the specific forms and proportions of the components of the limbs. That is to say the reason these forelimbs all show the same basic pentadactyl structure is that they were all descended from a pentadactyl ancestor, and developmental constraints (which themselves are merely historically contingent and not functional in origin) explain why the pentadactyl trait has been retained in multiple lineages over time.

It is important to note that, according to the above account, there is no functional explanation for the observed homology. Rather, this is a result of contingent factors that occurred in the history of the evolution of life on earth. If the “tape” of life were rewound to sometime before the existence of vertebrate organism, there is no reason to believe that anything resembling vertebrates with pentadactyl forelimbs would again arise.

Denton’s account starts from the (correct) premise that this homology has no functional explanation. He proposes a theoretical frameworks that he calls “structuralism”. According to this idea, the “homology” between those four limbs is an expression of deep, fundamental laws of physics and chemistry. His position is that, if life had arisen on other planets, we would still find vertebrates with pentadactyl limbs, for the much the same reasons we would expect to find quartz crystals under the geological conditions that produce them here on earth.

Now, this is entirely consistent with common ancestry in the broad sense. However, I do not see how common ancestry is a necessary or even contributory aspect of Denton’s account. Under his model, bats, cats, whales and humans could have been created by God initially as unicellular organisms. They could then continue to “evolve” over millions years into the forms that are determined by the underlying structural laws that Denton invokes, eventually arising with the “homologous” pentadactyl forelimbs that we now observe. Common ancestry would not be involved at any point.

I base this account of Denton’s views on the article linked below, as well as some of his videos produced by the DI.

https://bio-complexity.org/ojs/index.php/main/article/view/69

My concern is that his argument made there is entirely against a Darwinian functionalist version of “evolution” which, as has already been explained, is not part of the current understanding of how such homologies arise according to evolutionary theory. IOW, he is committing a strawman fallacy.

However, I readily admit that I have not read any of his books nor am I familiar with his thinking beyond what is explained in the sources listed above.

So I wonder if anyone who is more familiar with his work can give examples of how he argues against the standard evolutionary model that I have summarized above. If it turns out he has not done so, then we will have to conclude that he does not understand current evolutionary theory, and that his arguments are of little or no scientific value as a result. On the other hand, if he has made arguments against the current model, we can discuss them here and see if they hold up to scrutiny.

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One obvious question is: if the pentadactyl limbs of whales are a result of underlying structural laws, why don’t sharks have them too?

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You just need to read still a theory on crisis. It’s an interesting read. I think he is right on some things, wrong on others

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Remember, Denton rejects the modern evolutionary synthesis (despite accepting common descent), and believes evolution is “A Theory Still In Crisis”.

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Why would I need to do that, if the reason he thinks evolution is “in crisis” is that he does not understand evolution?

He rejects something that he believes to be “the modern evolutionary synthesis.” But does he actually know what he is rejecting? That is the question I am asking here, and it is being asked in good faith. From the one scholarly article (well, to the extent that “Bio-Complexity” is scholarly) I have read, and his other writings and videos of which I am aware, I see no good indication that he does. But I admit my familiarity with his work is not exhaustive.

Here is a passage from the article I cite where he attempts to describe what he understands to be the evolutionary account he is arguing against. This seems to me quite inaccurate a description:

According to the opposing paradigm, often referred to as functionalism, the main designs of life (pentadactyl limb, body plans, etc.) are not the result of physical law, that is, not immanent in nature or arising from intrinsic physical constraints inherent in biological matter, but rather the result of specific adaptations built additively by selection during the course of evolution, to serve particular functional ends, ends that are imposed by the environment and that are external to the organism itself. Adaptations built in this way are contingent, in the sense that they are undetermined by natural law. On this functionalist view, organisms are in essence like machines, complexes of functional parts arranged to serve particular adaptive ends. This is of course the currently prevailing, mainstream view. All Darwinists, and hence the great majority of evolutionary biologists, are functionalist by definition, because according to Darwinism all evolution is the result of adaptation to meet environmental contingencies.

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That’s definitely the basis of one of his ‘issues’ with evolution: that fish proteins were equally different from the equivalent proteins in horses, frogs, rabbits, turtles etc.

This is expected once it’s understood that all those creatures have been diverging from fish for the same amount of time, but Denton clung to the false ‘ladder’ view that rabbits evolved from frogs and should show more differences from fish than frogs do.

There’s a more detailed description on Wikipedia.

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He probably doesn’t understand it completely, but he rejects key elements which he does understand. For example, he’s ok with micro-evolution but not macro-evolution, which is why fundamentalists love him.

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Would that be the one where he claims Earth is a more suitable environment for humans than it is for dolphins?

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I don’t recall reading that in the paper. That sounds pretty weird.

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From that source:

Denton suggested that these data undermined the notion that fish were ancestral to frogs, which were ancestral to reptiles, which were ancestral to birds and mammals. If they were, then wouldn’t the difference in cytochrome C structures be increasingly different from carp to frog, to reptile, to mammal? How could the cytochrome c amino acid sequences for such a wide range of species all be “equidistant” from the sequence for bacteria? Molecular biologists quickly pointed out the fallacy in Denton’s argument. Just as there is no such thing as a “living fossil”, and all modern species are cousins, so too, the amino acid sequences for all living species have been evolving since the time of their divergence from a common ancestor. A modern carp is not an ancestor to a frog; frogs are not ancestors to turtles; turtles are not ancestors to rabbits. Similarly, the variations in eukaryotic cytochrome c structure with respect to bacteria are all due to mutations taking place since divergence from the common ancestor of these different organisms. It thus is not surprising that they show a similar level of divergence and equidistance of this type was even predicted and confirmed by researchers as early as 1963.

I think the answer to the question posed in the title of this thread is becoming clearer. Still, it would nice to hear from some of the supporters of ID. They likely know his work better than any of us.

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What Denton has done is invent the idea that the vertebrate forelimb is somehow required by the laws of physics, and then claims evolution is in crisis because of something he made up and has no support for. It’s not so much that he doesn’t understand it so much as inventing made up reasons to reject the theory.

There are other structures we could look at. For example, if mammals have tidal lungs because the laws of physics demands it, then why do birds have flow through lungs? Are birds violating the laws of physics? If the laws of physics demands that birds have feathers, then why don’t bats have feathers? If physics demands that the middle ear has three bones and the lower jaw has one bone as is found in mammals, then why do reptiles have a single middle ear bone and three lower jaw bones?

We haven’t even arrived at the genetic evidence for common ancestry which is an order of magnitude greater than that found at the morphological level.

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There’s an old critique of Denton’s work over at Talkorigins if people are interested.

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“Rejecting X” and “Rejecting some parts of X” are not the same thing.

And while the title of the 2016 book is “Evolution: Still a Theory in Crisis,” it’s clear to those who have read the book that it is not “evolution” that is being questioned, but only a particular way of thinking about evolution, which he calls the “Darwinian” or “neo-Darwinian” or more broadly the “functionalist” or “adaptationist” approach.

I remind the readers here of my earlier posting from the 2016 book, in which Denton said that even in the 1985 book, he never meant to cast doubt on evolution per se, but only on the Darwinian explanation of how evolution works, and that the title of the earlier book might have been less misleading for readers if he had called it “Darwinism: A Theory in Crisis.”

And if one asks the logical follow-up question, "Well, then, why wasn’t the title of the new book changed to “Darwinism: A Theory in Crisis” or “Functionalism: A Theory in Crisis”?, the answer would seem to be twofold:

1 – the 2016 book is intended as a review of the state of changes in evolutionary theory and in Denton’s thought since 1985; it makes constant reference to his first book; it is meant to be compared and contrasted with his first book. It makes sense, then, to alter the title of the new book as little as possible. Thus, the only change is the addition of the word “Still”.

2 – Books meant to be sold to the general reader, not just the biological specialist, try to keep their title non-academic-sounding. The general public has a notion of what “evolution” is; many of the public would find “Darwinism” or “Darwinian evolution” or “Functionalism” forbiddingly academic. If the original book had been titled: “The Darwinian Mechanism of Evolution: A Theory in Crisis,” it likely would not have sold as well. Ditto for the new book.

So nothing significant can be derived from the title of the new book. One has to be familiar with the contents. Now, the pro-evolutionists uniformly hated the 1985 book. But here, above, we have T J Runyon, who is pro-evolution and has apparently read the new book (unlike Jonathan Burke), saying that Denton is “right on some things, wrong on others.” So presumably Runyon would regard the 2016 books as a significant improvement on the 1985 one.

Nor is your familiarity with evolutionary theory. You’ve read far less of it than Denton has, as is quite evident from your comments here, which are based on a wholly derivative understanding of evolutionary theory, the understanding of a camp follower rather than one who is familiar with the actual writings of evolutionary theorists. You are a psychiatrist with less training in the relevant technical subjects – biochemistry, genetics, etc. – than Denton has, and you have no knowledge at all of the history of evolutionary thought, whereas he has read vastly in that area. So your judgments of what he knows, and what he doesn’t know, are like the judgments of an eighth-grade math student about what Einstein knows, or doesn’t know.

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TBH, that does not actually seem to address the specific argument made in the Denton paper I cited, which I believe is more recent than “Theory in Crisis.”

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So that would confirm my suggestion that he is committing a straw man fallacy, assuming my description of the current evolutionary explanation is correct.

Could you kindly point out the errors you believe I committed in my summary of the evolutionary account I gave in my OP? @John_Harshman thought it was “quite a nice description of the standard view”, so he might also benefit from whatever education you have to provide us on the actual theory of evolution.

The Fossil Record and Evolution - #113 by John_Harshman

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But it’s not that he just rejects part of it. He doesn’t accept it.

That explains the title!

…modern evolutionary synthesis. If he accepted the modern evolutionary synthesis, he wouldn’t be writing these books, he would be saying he accepts it, and he wouldn’t be of use to the DI.

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You said elsewhere that if someone doesn’t accept the “modern evolutionary synthesis” (which you couldn’t even define), that person doesn’t accept “evolution”; but that is absurd, as absurd as saying that if someone doesn’t accept the current majority view regarding gravity that he doesn’t accept “gravity”, or if someone doesn’t accept the current view of the nature of light, that he doesn’t believe in “light.” Someone can believe that a process has happened, while disagreeing with the majority of his colleagues over how it happened. Denton believes that evolution has happened, but disagrees with many people over how it happened. Denton is an evolutionist; you denied that, and you are still denying it.

If you would modify your earlier statements, and say, “Yeah, OK, I concede that Denton is an evolutionist, but I think his theory about how evolution works is wrong,” your contribution would be at least credible; but as you deny that Denton accepts evolution, your contribution can’t be taken seriously.

As far as I can tell from this discussion, the only people here who have firmly opined that Denton does not accept evolution, and is not an evolutionist, are yourself and Faizal Ali, neither of whom have read Denton’s recent books. That says a lot. And here is an example of a blatant error you’ve made, caused directly by your talking about Denton without reading him:

Utterly wrong. He accepts macroevolution, unreservedly. You’re making stuff up. And now you’ve been caught at it, like a burglar with his hand in the till.

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No. I said if someone doesn’t accept the modern evolutionary synthesis, then they don’t accept “evolution” as I am using the term “evolution”.

The title of those two books is staring you in the face. So is this Discovery Institute article).

I don’t think you’ve read his book. Either that or you’re playing with words.

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Hi, Eddie. Could we try stay focused on the topic of this thread. You seem to be by far the participant most well-acquainted with Denton’s writings, so your input would be quite valuable.

Has Denton acknowledged and responded to the aspects of current evolutionary theory that I outlined in my OP? If so, what is his response?

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I don’t believe you added that qualifier in your original statement. Please document the place.

And even if you did do so, then your original statement is of no value. Who cares you define “evolution,” when 150 years of usage goes against your definition? “Evolution”, when standing alone, typically refers to a process, not a theory. When someone is asked on the street, “Do you believe in evolution?” they assume that they are being asked if they think that human beings and all other living things arose by descent with modification from some crude, primitive life-form. They don’t assume they are being asked about their views on drift or gene flow. If you want to refer unambiguously to a theory rather than a process, you say “theory of evolution” not “evolution”.

Denton accepts “evolution”, but not all of what is said in current theories of evolution. It’s that straightforward. You and Faizal Ali are trying to muddy the waters by playing with words. It’s important to both of you to convince people here that no one in the ID movement accepts evolution, so you twist the normal meaning of words in order to achieve that end. The intellectually honest approach would be to say that some IDers accept evolution, but they are in the minority. Harshman has said this. But you won’t relent.

I have; in fact, I’ve read it with extreme care. You, on the other hand, haven’t read it at all, and you’re guessing about what’s in it. Your hatred of anything to do with Discovery and ID is causing you to be academically dishonest; you are reporting things about books you haven’t read, and then stubbornly defending statements you can’t justify, because you haven’t read the works in question. Your partisan motivation is now transparent for all here to see.