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Project Progress

I continued work, begun with Shelley Copley, on the possibility of a
“shadow biosphere,” i.e., the existence of molecularly distinct contemporary forms of microbial life descended from an alternative origin of life on Earth, in light of recent research, based on metagenomic techniques, which indicate that molecular methods are missing large numbers of low abundance, rare microbes. I have also been working on identifying anomalous physical systems that might provide telling signs of such microbes (physical systems that both resemble life as we know it and deviate from it in provocative ways) that might represent telling signs of such microbes. Desert varnish is the best candidate that I have identified so far: It has a stromatolite structure, with very thin chemical and mineralogical layers, and there isn’t a good abiotic explanation for the concentrations of manganese and iron that provide its striking color.

I begun investigations of the common claim that Darwinian evolution is a universal feature of all life, wherever it may be found in the universe; this belief is the basis for popular Darwinian definitions of 'life’ as well as reflected in the RNA world theory of the origin of life. Very briefly, I have found several reasons to question this common claim. First, the only two detailed arguments for it, found in the work of Dawkins and Dennett, are seriously flawed. Second, there are reasons to suspect that it doesn’t play a central role in microbial evolution, where lateral gene transfer dominates. Among other things, there is increasing evidence that “transformation” has a multiply “directed” character that is not in keeping with the core Darwinian ideas behind natural selection and “random” variation.