Episode VI: Return of Reason

[IDMR]

The first section of Ashby Camp's Critique. This is an experimental thread. We shall see how this one goes.

A Critique of Douglas Theobald's
29 Evidences for Macroevolution&
Intro by Ashby Camp
Part 1
One True Phylogenetic Tree

© 2001 Ashby L. Camp. All Rights Reserved. [Last Modified: 12 June 2002]


29 Evidences for Macroevolution, Douglas Theobald sets forth the evidence that he believes proves scientifically that all living organisms descended from one original living species. He does so by listing what he claims are 29 potentially falsifiable predictions of the hypothesis of universal common ancestry and presenting the evidence that he believes confirms each of those predictions.

Dr. Theobald does not address the origin of the first living thing or the mechanism by which that first organism diverged into every life form that has ever existed. His thesis is expressly restricted to the affirmation of universal common ancestry. In other words, he argues that, without knowing anything about how the first life arose or how it diversified, one can still be certain that all living things descended from the same ancestor. He states in the introduction (emphasis supplied):

In this treatise, I consider only macroevolution [which he labels a virtual synonym for universal common descent]. I do not consider microevolutionary theories, such as natural selection, genetic drift, sexual selection, theories of speciation, etc., which biologists use as mechanistic theories to explain macroevolution. Neither do I consider abiogenesis; I take it as axiomatic that an original self-replicating life form existed in the distant past.

In the conclusion, he says (emphasis supplied):

These previous points are all proofs of macroevolution alone; the evidences and the conclusion are independent of any explanatory mechanism. This is why scientists call macroevolution the fact of evolution. None of the 29 predictions directly address how macroevolution has occurred; nevertheless, the validity of the macroevolutionary conclusion does not depend on whether Darwinism, Lamarckism, or something else is the true mechanism of evolutionary change or not. The macroevolutionary conclusion still stands, regardless.

Dr. Theobald understandably seeks to free the claim of universal common ancestry from the debate about the sufficiency of evolutionary mechanisms, particularly the debate about Neo-Darwinism. It should not go unnoticed, however, that a bare claim of universal common ancestry is compatible with all mechanisms of common descent, including divine direction. So if God chose to have a reptile give birth to a bird, for example, that would be consistent with an a mechanistic argument for universal common ancestry.[1]

The fact that Dr. Theobald leaves the mechanism of descent completely open does not make his claim trivial. On the contrary, the claim of universal common ancestry is incompatible with the belief that God separately created more than one living thing. It therefore challenges the convictions of biblical creationists, progressive creationists, and all who believe that mankind was created separately from animals.

I address Dr. Theobald's predictions in the order in which he presented them. The italicized paragraphs following the predictions are quotations from his article. I quote only the prediction portion (or what I deem the relevant parts of it), not the alleged confirmations and potential falsifications. That would require me to duplicate the entire article. The accuracy of my references to the alleged confirmations or potential falsifications can be verified by consulting Dr. Theobald's article.

I appreciate the civility with which Dr. Theobald argued his case and hope that my response is in kind. I also appreciate his candor in acknowledging that science can never establish truth or fact in the sense that a scientific statement can be made that is formally beyond question. (That may seem obvious to those attuned to the philosophy of science, but I suspect it will come as a surprise to many.) So however much weight one assigns to the evidences adduced by Dr. Theobald, they cannot prove universal common ancestry in the sense of rendering its rejection illogical.[2] That being said, the focus of this response is on the weight to which the evidences are entitled.

I include here for convenient reference Dr. Theobald's Figure 1, which he labels 'The standard phylogenetic tree'.


PREDICTION 1: THE FUNDAMENTAL UNITY OF LIFE
According to the theory of common descent, modern living organisms, with all their incredible differences, are the progeny of one single species in the distant past. In spite of the extensive variation of form and function among organisms, several fundamental criteria characterize all life. Some of the macroscopic properties that characterize all of life are (1) replication, (2) information flow in continuity of kind, (3) catalysis, and (4) energy utilization (metabolism). At a very minimum, these four functions are required to generate a physical historical process that can be described by a phylogenetic tree.

If every living species descended from an original species that had these four obligate functions, then all living species today should necessarily have these functions. Most importantly, they should have inherited the structures that perform these functions. The genealogical relatedness of all life predicts that organisms should be very similar in the particular mechanisms and structures that execute these basic life processes.

The alleged prediction and fulfillment are:

If universal common ancestry is true, then all organisms will have one or more traits in common.

All organisms have one or more traits in common.

Unless one inserts an additional premise imposing a limit on the degree to which descendants can vary (which would require specification of a mechanism of descent), the claim of common ancestry does not require that all of the descendants share one or more traits. There is no logical reason why completely novel organisms could not arise in one or more lineages. Absent specification of a mechanism of descent, which Dr. Theobald purposefully avoids, there is no way to tether the traits of the descendants to those of the common ancestor.

The belief that evolution predicts biologic universals is one of evolution's major illusions. (ReMine, 92.) As Walter ReMine says:

First, evolution does not predict that life would arise precisely once on this planet. If there were two or more unrelated systems of life, then evolutionary theory would effortlessly accommodate that situation.[3]
Second, even if life originated precisely once, then evolutionary theory would still not predict biologic universals. Shortly after life's origin, nothing prevented life from branching and leading separate lineages to higher life forms entirely lacking the known biologic universals.
Third, evolutionary loss and replacement processes could prevent biologic universals. If one organism is a distant ancestor to another, then nothing in evolution predicts the two must share similarities. If evolution were true, then distant ancestors and descendants (as well as sister groups) can be totally different.
Evolution never did predict biologic universals, it merely accommodated them. (ReMine, 92-93.)
Biophysicist Cornelius G. Hunter concurs. He writes:

There is yet another reason that the universality of the genetic code is not strong evidence for evolution. Simply put, the theory of evolution does not predict the genetic code to be universal (it does not, for that matter, predict the genetic code at all). In fact, leading evolutionists such as Francis Crick and Leslie Orgel are surprised that there aren't multiple codes in nature.
Consider how evolutionists would react if there were in fact multiple codes in nature. What if plants, animals, and bacteria all had different codes? Such a finding would not falsify evolution; rather, it would be incorporated into the theory. For if the code is arbitrary, why should there be just one? The blind process of evolution would explain why there are multiple codes. In fact, in 1979 certain minor variations in the code were found, and evolutionists believe, not surprisingly, that the variations were caused by the continuing evolution of the universal genetic code. Of course, it would not be a problem for such an explanation to be extended if it were the case that there were multiple codes. There is nothing wrong with a theory that is comfortable with different outcomes, but there is something wrong when one of those outcomes is then claimed as supporting evidence. If a theory can predict both A and not-A, then neither A nor not-A can be used as evidence for the theory. When it comes to the genetic code, evolution can accommodate a range of findings, but it cannot then use one of those findings as supporting evidence. (Hunter, 38.)
The fact that some leading evolutionists believe early life forms were biochemically distinct from modern forms confirms that evolution does not predict biologic universals. Robert Shapiro, for example, entertains the possibility of finding living relics of an original protein-based life form that lacked DNA and RNA. (Shapiro, 293-295.) Likewise, A. G. Cairns-Smith thinks that descendants of ancient crystalline clay organisms may be all around us. He states: Evolution did not start with the organic molecules that have now become universal to life: indeed I doubt whether the first organisms, even the first evolved organisms, had any organic molecules in them at all. (Cairns-Smith, 107.)

On the other hand, ReMine argues that biologic universals are a prediction of his message theory of creation, which says all life was constructed to look like the unified work of a single designer. (ReMine, 94.) So evolution does not predict the unity of living things, but at least one theory of creation does.

Of course, the biochemical similarity of living things fits easily within a creation framework. As biochemist Duane Gish explains:

A creationist would also expect many biochemical similarities in all living organisms. We all drink the same water, breathe the same air, and eat the same food. Supposing, on the other hand, God had made plants with a certain type of amino acids, sugars, purines, pyrimidines, etc.; then made animals with a different type of amino acids, sugars, purines, pyrimidines, etc.; and, finally, made man with a third type of amino acids, sugars, etc. What could we eat? We couldn't eat plants; we couldn't eat animals; all we could eat would be each other! Obviously, that wouldn't work. All the key molecules in plants, animals, and man had to be the same. The metabolism of plants, animals, and man, based on the same biochemical principles, had to be similar, and therefore key metabolic pathways would employ similar macromolecules, modified to fit the particular internal environment of the organism or cell in which it must function. (Gish, 277.)
As for the alleged fulfillment, I do not doubt that all living things have carried out the basic functions of life in similar ways, but there are many organisms, past and present, about which we know nothing. It is impossible to be certain that none of these organisms is (or was) biochemically unique (witness the speculations of Shapiro and Cairns-Smith). The claim that all organisms have one or more traits in common is true in the sense that all living things necessarily have the traits by which life is defined, but that is simply a tautology - living things all have the traits of living things.

[David]

You might want to touch that up IDMR, it looks like all the hypertext codes got turned into that #8221 stuff.

[IDMR]

You might want to touch that up IDMR, it looks like all the hypertext codes got turned into that #8221 stuff.

I know. Busy right now.

::calculating look::

Heyyyyyy, o ye of over three hundred posts, would you mind lending me some of your typing monkeys?

[David]

They're all busy typing up some reports.....


Hmmmmmmmmm, no wonder my GPA has gone down.

[IDMR]

At any rate, it is done.

[David]

Looks better

[IDMR]

::bumps:: Can someone do a short rebuttal to this? I will do one on Monday, but I am a little busy right now.

::looks at The Monkey of Almost Six Hundred Posts:: David, you?

[David]

Sorry, I'm busy ripping apart Resident Commie at the moment.

[Mr Bean]

And that makes number 600
Or he just posted 600 posts and its relfect here
Not that I care either way but it inflates my own post count and thus my intanglbe sense of self worth and that makes it all good

[David]

Bow to the monkey Beano, and I may let you live when I become an Admin ( and it will happen eventually!)

That's nice, Dave, but don't clutter up the thread, please.

[Ai Phling Pu]

Evolution is for rednecks who couldn't score with the cousin and discovered the monkey couldn't get away. (Had to justify it somehow...)

[IDMR]

Ai Phling Pu, I would advise you to at least make an attempt in actually discussing the topic.