The Fossil Record and Evolution

What does that mean, if you have any clue?

You have these primal patterns or body plans that arise from what he calls “the law of form”. Predetermined body plans. And Darwinian processes can only create variants of these body plans.

if you are talking about human genome that produce more human genome i agree. but we are talking about evolution of genomes from non genomes or from other types of genomes.

of course that it base on the genomic data (or morphology). but evolution doesnt predict such hierarchy. if we never had such hierarchy evolution will have no problem.

Are we talking about phyla, or what? And is this some kind of D’arcy Thompson stuff?

No, we aren’t talking about genomes from non-genomes. And of course the genomes of new species also arise from the genomes of their ancestors. Are you denying that speciation happens?

You have given no reason for this claim.

I’m not sure what you are trying to say there.

I doubt that Darwin would have ever suggested evolution, were it not for the clear evidence of a hierarchy.

His favorite example is the tetrapod limb

He refers to his work numerous times. Then people like Brian Goodman. Stuart Newman, Stuart Kauffman and even Gould’s chapter on structuralism in Structure

So, something like vertebrate classes, perhaps many orders. Any major change. Now I’m trying to figure out what law of form changes a fin into a leg.

https://s3.amazonaws.com/academia.edu.documents/39472547/The_protein_folds_as_platonic_forms_new_20151027-28022-165ttfo.pdf?response-content-disposition=inline%3B%20filename%3DThe_Protein_Folds_as_Platonic_Forms_New.pdf&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWOWYYGZ2Y53UL3A%2F20200114%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20200114T183133Z&X-Amz-Expires=3600&X-Amz-SignedHeaders=host&X-Amz-Signature=a1ad9054f2e0a179fa461ca59cb6b3078ccada379ab05c92c233450bb9798505

Still not getting it. If the pentadactyl limb is supposed to be an inevitable consequence of the basic properties of matter, then why do so many early tetrapodomorphs have more than 5 digits? Why do so many extant tetrapods have fewer? And what about widespread polydactyly?

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There’s several kinds of matter. Most of it forms pentadactyl limbs, but the other kinds form limbs with 11 digits, or 8 digits, or whatever.

@scd wrote that evolution does not predict the nested hierarchy. Denton appears to be saying the same thing in the video

The video below explains it. I agree he rejects Darwinism. If you think what he says here amounts to an acceptance of evolution, you need to convince me, because it sounds like no form of evolutionary theory I’ve ever heard, but you know more than me.

Not that I can tell. What in there are you interpreting that way?

Once again, as far as I’m concerned the core element of evolution is common descent. How mutations get into genomes is not the core.

Yes, that’s our point of disagreement. However, even so, it is not entirely clear to me that he accepts common descent. IDC theorists are rarely consistent and coherent in their ideas.

Structuralism expains why, when you go around the world and examine examples of quartz, you repeatedly find the same crystal structure. The laws of physics and chemistry predispose to the creation of these structures. It is not the result of all quartz minerals sharing a common ancestor.

Denton then goes on to say that this is also the reason that, when you look at tetrapod limbs, you repeatedly observe that there is one proximal long bone, connected to two long bones in the middle, and five digits at the end. Common descent does not explain or account for this. “Structuralism” does.

I cannot accept that as a mere variant or modification of the current theory of evolution. And when he does on to say this structuralism is consistent with “Design”, he becomes full-blown creationist, IMHO. At the very least, I think there are strong logical grounds to categorize him as such.

He does

It seems quite clear to me.

OK, so let’s see if I am understanding his position correctly. Consider the following observation:

By the usual understanding of “common descent”, 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. Denton is correct, then, in stating there is no functional explanation for the fact that the the limbs are all pentadactyl. The evolutionary explanation 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.

Denton’s structuralism denies this explanation (or, more accurately AFAIK does not even acknowledge this explanation). His position is this is an expression of deep, fundamental laws of physics and chemistry and that if life arose on other planets we would still find vertebrates with pentadactyl limbs for 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 admit I have not read any of his books, but I have watched his videos and read some of his articles such as the one below. I am not aware of any instance where he has affirmed that common descent is demonstrably and undeniably true, to the extent that even Behe has done so. If he has done so, then feel free to cite where he has.

But, as I have said before, this is only peripheral to my position. Even if he does begrudgingly acknowledge that Darwin’s core idea, common ancestry, is correct, I still do not consider that sufficient to define him as one who accepts evolution and not creationism. I am using those terms in the sense of defining a person’s underlying assumptions, motivations and goals, and it is clear to me where Denton is coming from.

Mostly, I’d like confirmation of whether I am understanding Denton’s position more or less accurately, since there seems to be some doubt about that.

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

Yes, that’s what we disagree on. That was quite a nice description of the standard view in your first paragraph. I’m by no means an expert on Denton, so I can’t do much to clarify his beliefs. Still, I find nothing in that abstract to challenge my previous impression. In fact, I find nothing in the paper that’s at all relevant to any opinions he may have on common descent.

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OK, thanks. That is settled.