Online research in philosophy

Here I advance two related evolutionary propositions. (1) Natural selection is most often considered to require competition between reproducing “individuals”, sometimes quite broadly conceived, as in cases of clonal, species or multispecies-community selection. But differential survival of non-competing and non-reproducing individuals will also result in increasing frequencies of survival-promoting “adaptations” among survivors, and thus is also a kind of natural selection. (2) Darwinists have challenged the view that the Earth’s biosphere is an evolved global homeostatic system. Since there is only (...) one biosphere, reproductive competition cannot have been involved in selection for such survival-promoting adaptations, they claim. But natural selection through survival could reconcile Gaia with evolutionary theory. (shrink)

Lateral gene transfer (LGT), the exchange of genetic information between (primarily prokaryotic) lineages, not only makes construction of a universal Tree of Life (TOL) difficult to achieve, but calls into question the utility and meaning of any result. Here I review the science of prokaryotic LGT, the philosophy of the TOL as it figured in Darwin’s formulation of the Theory of Evolution, and the politics of the current debate within the discipline over how threats to the TOL should be represented (...) outside it. We could encourage a more realistic and supportive public understanding of evolution by admitting that what we believe in is not a unified meta-theory but a versatile and well-stocked explanatory toolkit. (shrink)

Our understanding of what microbes are and how they evolve has undergone many radical shifts since the late nineteenth century, when many still believed that bacteria could be spontaneously generated and most thought microbial “species” (if any) to be unstable and interchangeable in form and function (pleomorphic). By the late twentieth century, an ontology based on single cells and definable species with predictable properties, evolving like species of animals or plants, was widely accepted. Now, however, genomic and metagenomic data show (...) that lateral gene transfer compromises this picture of stability and predictability, and refocuses our attention on multilineage communities. Treating such communities as unstable but identifiable evolving “individuals” makes us again pleomorphists, of a sort. (shrink)

The genome contains elements which are most easily understood as the products of selection operating at the level of the genome, without regard to phenotypic effect. The properties of such elements, and more general implications of molecular biological data, are discussed.