Friday, November 12, 2010

Evolution News & Views on the Human Genome Project

The Discovery Institute's Evolution News & Views blog has posted an article (seriously, the author is given as "Evolution News & Views," so it's the intelligently designed product of another intelligently designed product, designed, in the opinion of its own designers, by intelligently designed products, so we're dealing with massively recurrent design here) on "The human genome project ten years later."  Research on the human genome has, as the blog sees it, has undermined "Darwinism" in a couple of different ways.

First, it notes, research has found that much so-called "junk DNA" is actually functional.  This is presumably relevant because, to ID proponents (or at least to their blogs), "junk" DNA is relevant as evidence for common ancestry and natural selection only because it's supposed to be useless.  But of course "junk" DNA, like other vestigial structures, is evidence because it is homologous to structures with entirely different functions from whatever function it might have.  It is an example of "parahomology," adaption of one structure to serve an entirely different use.  In principle, a pseudogene or endogenous retrovirus is evidence of the same kind as the homologies among a whale's flipper, a bat's wing, and a human arm and hand: even when they are all fully functional, their detailed similarities aren't required by their divergent functions, and are far easier to explain in terms of descent with modification from a common ancestor than in terms of separate origins (whether "common design" or some sort of separate evolution to fit their different niches).  Vestigial organs have from Darwin on been defined as lacking the most obvious or important function of their homologs, not as lacking all function, and there's no obvious reason this shouldn't apply to vestigial genetic elements.

On the other hand, large swaths of the genome in fact not only haven't been discovered to serve any function, but there is some evidence that they really don't have any function to discover; at least, they can be removed without any discernible effect.

Anyway, the blog's second, and main, argument, is that evolution (and the blog seems to mean common descent, not just naturalistic mechanisms to produce this effect, since it speaks of the inference of "evolutionary relatedness") is undermined because "scientists are coming to a sobering conclusion that perhaps their models and assumptions on the nature of disease may be mistaken."  Rather than most non-infectious diseases being, like sickle-cell anemia or cystic fibrosis, the results of single mutations to single genes, most, like breast cancer, are the result of subtle and hard-to-trace interactions among dozens or hundreds of genes. Given that the genome isn't literally a "blueprint," with one set of nucleotides corresponding to one particular trait, but that polygeny (multiple genes influencing a single trait) and pleiotropy (multiple traits affected by a single gene) have been necessary terms in genetics for decades, arguably this was more of a disappointment than an actual surprise to anyone: it makes finding cures for things more difficult but is pretty consistent with what has been known about genes since before the Human Genome Project was started.

The blog's opinion on this research concludes:
 Given the presupposition that a complex organism is engineered, then the parts themselves must be taken within the context of the whole. ... A reductionist, neo-Darwinian view of the human genome does not seem to have explanatory power regarding disease. This is a clear case where some scientists' dedication to the presupposition that similar DNA sequences means whole organism similarity, the same presupposition that many have used to argue for evolutionary relatedness among species and against man being anything more than another animal, has, 138 million dollars later, lead to more dead ends than cures.
 I find myself bemused.  From intelligently designed kitchenware that differs from other pots and pans because of single, "reductionist" features such as stickproof coating, to cars and computers chock-full of features and components that can be discussed and evaluated in isolation, "reductionism" seems an ubiquitous feature of human design.  It "does not seem" to me that one can simultaneously claim, as various human writers on Evolution News & Views have done, that "design" in nature is recognized by analogy to human design, and that "design" in nature can be recognized because it resists analysis in terms of modules, reductionism, and other methods used by human designers.

There is also an element of desperation in seizing on the discovery that trying to examine things as a collection of disparate components that produce no more than the sum of their parts doesn't always work.  I suspect, again, that actual scientists figured this out a long, long time ago ("make everything as simple as possible, but not simpler," as Einstein uncontroversially noted), but one has to look for simple patterns before one can make out the complicated ones.

And one must really wonder if the blog, or its human designers, assume that other animals really can be explained more reductively and simply than Homo sapiens.

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