Tuesday, October 05, 2004

Tipler, Part One

Frank Tipler's contribution to William Dembski's anthology Uncommon Dissent is entitled “Refereed Journals: Do They Insure Quality or Enforce Orthodoxy?“ In it he writes:

“Peer” review is very unlikely to be peer-review for the Einsteins of the world. We have a scientific social system in which intellectual pygmies are standing in judgment of giants. (P. 121) (Emphasis in original)

It would be easier to take Tipler seriously if it weren't so obvious that he regards himself as one of those giants whose work has been judged by pygmies. He unloads many criticisms of the current peer-review system used by academic journals. Most academics would agree with most of the criticisms Tipler makes, but they would quickly point out that we do need some sort of quality control system in journals and no one has suggested a better system than the one in place. Tipler makes a few proposals in this regard, but they are not vey impressive.

But we will deal with those in a later post. In this post we will deal with one example of Tipler being less than accurate, to put it kindly, in his descriptions of other people's work. Two further examples will be given in a later post.

We begin with this one:

The most radical scientific theory with religious implications is Intelligent Design. It is impossible to get any member of the National Academy of Sciences to consider it seriously. The typical reaction of such scientists is to foam at the mouth when the phrase “intelligent design” is mentioned. I have recently experienced this. In the fall of 2002, I arranged for Bill Dembski to come to Tulane to debate a Darwinian on the Tulane faculty. (This faculty member was appropriately named Steve Darwin). Bill presented only the evidence against Darwinism in the debate, while Steve's response unfortunately had quite a few ad hominem remarks. Steve has continued to be friendly to me personally. But ever since the Dembski/Darwin debate, another evolutionist on the Tulane faculty - who shall remain nameless! - glares at me every time he sees me. Before the debate he and I were friends. Now he considers me a monster of moral depravity. Yet if the religious implications of Intelligent Design are ignored, if the theory is called something besides “intelligent design” then the scientific community is quite open to intelligent design. The evolutionist Lynn Margulis, a member of the National Academy of Sciences, has made much the same criticism of modern Darwnism that Michael Behe and Bill Dembski have made. She has put her arguments in a book titled Acquiring Genomes: A Theory of the Origin of Species, written with her son Dorion Sagan. The book has a foreward written by Ernst Mayr, a retired professor of evolutionary biology at Harvard, who agrees with Margulis that Darwinism has the problems she discusses. This is especially significant since Mayr is not just an ordinary evolutionist. He has been called the “Dean of American Evolutionists”, and he is one of the founders of the Modern Synthesis, which is the modern version of Darwinism. Mayr does not think that Margulis has resolved the problems with Darwinism, nor do I. I should mention that, to her credit, however, she cites Michael Behe's Dariwn's Black Box in her book. (P. 125-126)

Sorry for the lengthy quote, but everything you need to know about Tipler is contained within it. It is his description of Margulis' work and Mayr's foreward that I want to focus on, but the remainder of the paragraph deserves mention too.

He begins by claimng that the NAS refuses to take ID seriously. But what, exactly, are they supposed to consider? There is no theory of intelligent design, as I'm sure Tipler is aware. There is only a motley collection of criticisms to current orthodoxy, coupled with the assertion that an unfathomable intelligence must have done something at some point in natural history. ID proponents still have not put forward any serious research program based on their work.

Next comes an anecdote about a nameless person who was angry at Tipler for inviting Dembski to Tulane University. Wow! If I'd known he had evidence like that up his sleeve I would never have thought to challenge his assertion about scientists frothing at the mouth. Of course, this sort of anecdote plays well with non-scientists already inclined to take ID seriously, but carries no weight with anyone interested in a serious discussion of scientific issues.

Then he has the nerve to take his colleague, Steve Darwin, to task for using ad hominem attacks. Sadly, most of Tipler's essay is one long smear against the scientific community. I will document this in later postings. Meanwhile, ID proponents are perfectly happy to spread the most vicious smears of their opponents in any venue other than ostensibly serious debates. Somehow that doesn't bother Tipler.

And, of course, it is not a failure to take ID seriously that prompts scientists, NAS members or not, to froth at the mouth when it comes up. Quite the opposite. It is the fact that ID proponents routinely tell the world they have slain the Darwinian dragon and have started a revolution in science, when in reality they have simply made fallacious criticisms of current theory and have offered no useful alternative of their own, that gets scientists a tad peeved. If Tipler wants to be part of this discussion, then he needs to explain why the countless counterarguments made by scientists in response to ID are wrong.

But that is all preamble. The real action comes when Tipler starts talking about Acquiring Genomes. Lynn Margulis is making the same criticisms of Darwinism as Behe and Dembski? Ernst Mayr agrees with these criticisms? No way. No one familiar with either Margulis or Mayr could possibly take this seriously.

Now, ID proponents are perfectly happy to glom on to any anti-evolutionary argument that has ever been made, especially when it comes from someone as respected as Lynn Margulis. So in that sense I'm sure that Behe and Dembski would be happy to endorse Margulis' criticisms of current theories of evolution. But the fact remains that both gentlemen make arguments entirely different from what Margulis is saying.

Behe's argument has to do with “irreducible complexity”. A system is irreducibly complex, according to Behe, when it has several, well-matched, indispensable parts. This is said to be a problem for evolution because if the system is non-functional until all of the parts are in place, there are no precursor systems for selection to act on. This argument is obviously incorrect, as has been pointed out numerous times. But in the present context what is relevant is that it is entirely an engineering objection. The claim is that natural selection acting on small genetic variations can't craft particular configurations of parts.

Meanwhile, Dembski's rallying cry is “complex specified information”. I will not rehash what this is, but suffice it to say that in its proposed application to biology it is nothing but an addendum to Behe's ideas. Dembski is explicit in his writing that he thinks that natural selection acting on small variations can craft complex systems. It is only certain kinds of complexity evolution can't account for.

That is not the objection that Margulis is making. Her argument against current orthodoxy has nothing to do with engineering or the power of natural selection. Rather, she is concerned about the sources of the variation on which selection acts. She believes that the role of genetic mutations has been overstated and that actually symbiosis is a far more important mechanism in accounting for the origin of variation. Here's a typical quote, from Acquiring Genomes:

We certainly agree that random heritable changes, or gene mutations, occur. We also concur that these random muttions are expressed in the chemistry of the living organism. Altered proteins that can be traced back to gene mutations in living organisms have been massively demonstrated. The major difference between our view and the standard neodarwinist doctrine today concerns the importance of random mutation in evolution. We believe random mutation is wildly overemphasized as a source of hereditary variation. (P. 11)

So much for Tipler's first assertion, that Margulis is making the same criticisms as Behe and Dembski. Far worse, however, is his gross distortion of what Ernst Mayr said in his foreward to Margulis' book. I can think of no better refutation of Tipler's claim than to transcribe for you the relevant part of Mayr's foreward. This will be a bit long, but I think it's important to document how loose Tipler is being with the truth. Here's Mayr:

When I got my degree at the University of Berlin, almost eighty years ago, biology consisted of two branches, zoology and botany. What dealt with animals was zoology, and everything else, including fungi and bacteria, was assigned to botany. Things have improved since then, particularly since the discovery of the usefulness of yeast and bacteria for molecular studies. Most of these studies, however, strengthened the reductionist approach and thus fostered a neglect of the major actors in evolution - individuals, populations, species, and their interactions.

The authors of Acquiring Genomes counter this tendency by showing the overwhelming importance of interactions between individuals of different species. Much advance in evolution is due to the establishement of consortia between two organisms with entirely different genomes. Ecologists have barely begun to describe these interactions.

Among the millions of possible interactions (including parasitism), the auhtors have selected one as the principal object of their book: symbiosis. This is the name for mutual interaction invovling physical association between “differently named organisms”. The classical examples of symbiosis are the lichens, in which a fungus is associated with an alga or a cyanobacterium. At first considered quite exceptional, symbiosis was eventually discovered to be almost universal. The microbes that live in a special stomach of the cow, for instance, and provide the enzymes for its digestion of cellulose are symbionts of the cow. Lynn Margulis has been a leading student of symbiosis. She convinced the cytologists that mitochondria are symbionts in both plant and animal cells, as are chloroplasts in plant cells. The establishment of a new form from such symbiosis is known as symbiogenesis.

For many years, Margulis has been a leader in the interpretation of evolutionary entities as the products of symbiogenesis. The most startling (and, for some people, unbelievable) such event was the origin of the eukaryotes by the fusion of an archaebacterium with some eubacteria. Both partners contributed important physiological capacities, from which ensued the great evolutionary success of the eukaryotes - the cells from which all animals, plants, and fungi are built.

Symbiogenesis is the major theme of this book. The authors show convincingly that an unexpectedly large proportion of evolutionary lineage had their origins in symbiogenesis. In these cases a combination of two totally different genomes form a symbiotic consortium which becomes the target of selection as a single entity. By the mutual stability of the relationship, symbiosis differs from other cases of interaction such as carnivory, herbivory, and parasitism.

The acquisition of a new genome may be as instantaneous as a chromosomal event that leads to polyploidy. The authors lead one to suggest that such an event might be in conflict with Darwin's principle of gradual evolution. Actually, the incorporation of a new genome is probably a very slow process extending over very many generations. But even if instantaneous, it will not be any more saltational than any event leading to polyploidy.

The auhtors refer to the act of symbiogenesis as an instance of speciation. Some of their statements might lead an uninformed reader to the erroneous conclusion that speciation is always due to symbiogensis. Speciation - the multiplication of species - and symbiogensis are two independent, superimposed porcesses. There is no indication that any of the 10,000 species of birds or the 4,500 species of mammals orginated by symbiogenesis.

Another of the authors' evolutionary interpretations is vulnerable as well. They suggest that the incorporation of new genomes in cases of symbiogenesis restores the validity of the time-honored principle of inheritance of acquired characters (what is called “Lamarckian inheritance”). This is not true. The two processes are entirely difference. Lamrackian inheritance is the inheritance of modifed phenotypes, while symbiogensis involves the inheritance of incorporated parts of genomes.

The foreward goes on for a few more paragraphs, but contains nothing further of relevance here. As I said, I quote this at such length because even skimming it makes it clear that Mayr is lukewarm at best about Margulis' criticisms of orthodox theory, and certinly says nothing remotely favorable about ID, or Behe, or Dembski. As far as I can tell, Tipler's assertion about Mayr agreeing with Margulis' criticisms is based entirely on Mayr's assertion that modern evolutionary theory has focussed too much on genes and not enough on ecological interactions. I have no doubt this is true (though I would point out that this focus on genes over ecology is explained largely by the fact that genes are easier to study than ecological interactions). None of this, however, has to do with explanatory deificiencies in neodarwinian theory.

Anyone reading Tipler's essay without already being familiar with the work of Mayr and Margulis will get the impression that Ernst Mayr thinks there's something of merit in the writings of Behe and Dembski. This impression is totally false, as I have shown.

Oh, and that reference to Behe in Margulis' book? Here it is:

Anthropocentric writers with a proclivity for the miraculous and a commitment to divine intervention tend to attribute historical appearances like eyes, wings, and speech to “irreducible complexity” (as, for example, Michael Behe does in his book, Darwin's Black Box. (P. 202)

Not exactly a favorable mention. I would also point out, on Behe's behalf, that the term “irreducible complexity” is completely misused by Margulis here.

Sadly, this is hardly the only example of Tipler being dishonest in his presentations of other people's work. I will consider two further examples in a later post.


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