Tuesday, March 01, 2005

The Unspeakable Gods of the Abyss

Creationists and Intelligent Design folks routinely resort to God-of-the-Gaps arguments in order to find room for a creator in the workings of nature, and biologists routinely remind them how many of the gaps have been filled in over the years. Gaps remain, however, including gaps that are perhaps not likely to be filled in any time soon, most obviously in such intrinsically difficult issues as the origin of living things. Even things that happened more recently than 4 billion years ago are also hard to figure out. For example, it has become more and more clear over the last few years that we don’t have a very good handle on what gives with the microbial majority of living things. Only a small percentage of single-celled organisms can be cultured by current methods, but we’ve know from DNA-sequencing experiments on natural samples that there must be many, many unknown forms, including lots of members of the mysterious domain of the Archaea, which, it transpires, are not a handful of weird relics lurking in thermal vents as they first appeared by in 1977, but ecologically important members of many ordinary environments. Our branch of the tree of life also turns out to be bushier than we thought—many unknown eukaryotes are also hidden somewhere if we could only figure out how to grow and identify them. Meanwhile, we have a more general problem than simply accounting for all these cryptic organisms. We have a basic problem in figuring out how to make sense of the phylogeny of all these bugs since they regularly swap genes, thus seriously tangling up the usual diagrams.

Traditional evolutionary theory was devised to make sense of multi-cellular eukaryotes. Indeed, as botanists like Verne Grant have complained, the historical bias of the theory has effectively been yet more parochial, privileging animals over plants, even though flowers and trees don’t evolve or speciate in exactly the same fashion as birds and beasts. In current phylogenies plants, animals, and even fungi occupy the same branch of the tree while most of the fundamental diversity of life lies elsewhere. To the extent that evolutionary theory is based on the usual suspects, it suffers from a serious sampling problem.

All in all, if you want to assert the possibility that big surprises may await us in the understanding of living things, you won’t have any trouble finding plenty of gaps that remain to be filled in. What the Creationists and other theists don’t seem to recognize, however, is that the existence of gaps is not an argument for their view of things. What emerges from dark is much more likely to be even less congruent with theological preconceptions than what is already known because the journey of the sciences is an expedition away from the comfortable territory of the human into an undefined Antarctica. If traditional evolutionary thinking is objectionably zoomorphic, theological reasoning is even more wedded to a view of things dependent on HOX genes. ID, for example, involves the notion of an agent that makes living things, a rather unimaginative piece of theorizing. So far as we know, the only entities in the universe that can be said to act at all are members of certain terrestrial phyla so the God, gods, or aliens who supposedly made life turn out to be a run-of-the-mill bilatrians, real or virtual organisms imagined in our image. Unfortuanately, the trend of discoveries in biology suggest that it’s a good bet that what dwells in the gaps will not turn out to be something so familiar as a deity or a Vulcan. Think of something from a Lovecraft story.

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