Why People Reject Universal Common Descent- an Open Letter to Joshua Swamidass

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Over on Peaceful Science Joshua Swamidass wrongly accuses ID of rejecting and arguing against Universal Common Descent. But that is false as ID doesn't care. ID says if it happened it happened via intelligent design. So please stop conflating ID with the people who accept it as the best, and still only, scientific explanation for our existence.

That said, PEOPLE do argue against and reject UCD. That is because it is an untestable concept, Joshua. You may disagree but you don't have any science to refute it. No one can test the claim that bacteria can evolve into something other than bacteria. No one can test the claim that fish can evolve into something other than fish.

You would think that with prokaryotes, archaea and eukaryotes some lab or labs would be busy injecting one into the other to see what, if anything, happens. Or even injecting mitochondria into existing proks and archaea to see what, if anything, happens.

Maybe they have and it's just that no one reports on failures of such experiments.

But then again, Joshua thinks the chimp-human ancestry is confirmed by the fact that rats and mice are more genetically different than chimps and humans. I still don't understand that reasoning but that is what he has said and wrote about.

Unfortunately for Joshua no one has ever been able to demonstrate that what makes a chimp a chimp and a human a human is based on genetics or genetics combined with the interactions with the environment. So that would be a problem. It also means that you don't have a mechanism for producing the differences observed. Again, you may disagree but until you show the science, your disagreement is hollow. As Dr. Michael Denton wrote:

To understand the challenge to the “superwatch” model by the erosion of the gene-centric view of nature, it is necessary to recall August Weismann’s seminal insight more than a century ago regarding the need for genetic determinants to specify organic form. As Weismann saw so clearly, in order to account for the unerring transmission through time with precise reduplication, for each generation of “complex contingent assemblages of matter” (superwatches), it is necessary to propose the existence of stable abstract genetic blueprints or programs in the genes- he called them “determinants”- sequestered safely in the germ plasm, away from the ever varying and destabilizing influences of the extra-genetic environment.

Such carefully isolated determinants would theoretically be capable of reliably transmitting contingent order through time and specifying it reliably each generation. Thus, the modern “gene-centric” view of life was born, and with it the heroic twentieth century effort to identify Weismann’s determinants, supposed to be capable of reliably specifying in precise detail all the contingent order of the phenotype. Weismann was correct in this: the contingent view of form and indeed the entire mechanistic conception of life- the superwatch model- is critically dependent on showing that all or at least the vast majority of organic form is specified in precise detail in the genes.

Yet by the late 1980s it was becoming obvious to most genetic researchers, including myself, since my own main research interest in the ‘80s and ‘90s was human genetics, that the heroic effort to find information specifying life’s order in the genes had failed. There was no longer the slightest justification for believing there exists anything in the genome remotely resembling a program capable of specifying in detail all the complex order of the phenotype. The emerging picture made it increasingly difficult to see genes as Weismann’s “unambiguous bearers of information” or view them as the sole source of the durability and stability of organic form. It is true that genes influence every aspect of development, but influencing something is not the same as determining it. Only a small fraction of all known genes, such as the developmental fate switching genes, can be imputed to have any sort of directing or controlling influence on form generation. From being “isolated directors” of a one-way game of life, genes are now considered to be interactive players in a dynamic two-way dance of almost unfathomable complexity, as described by Keller in The Century of The Gene- Michael Denton “An Anti-Darwinian Intellectual Journey”, Uncommon Dissent (2004), pages 171-2 

We do NOT know what makes an organism what it is. That is we do not know what determines form. That alone makes it really difficult to say one form can evolve into another, regardless of the underlying mechanisms. And it squashes the notion that you can say anything about evolutionary relationships via genetic comparisons.

So you see, Joshua, the concept is untestable. And just because some people find it pleasing, that is not a replacement for science. Dr. Neil Shubin thinks that fish evolved into tetrapods. Someone should be using targeted mutagenesis and real selection, to try to test that concept using existing fish embryos. Yes, I know the outcry- "But today's fish ain't those fish that evolved into tetrapods"- to which I respond- thank you for conceding that the claim is untestable.

Before I let you go I also want to say something about the fossil record. The vast bulk of the fossil record, greater than 95%, is of marine invertebrates. Which, given our understanding of how that process works, is very understandable. But yet, in that vast bulk, evidence for universal common descent is absent and slight variations abound.


sincerely,

JoeG