Online research in philosophy

One current version of the internalism/externalism debate in evolutionary theory focuses on the relative importance of developmental constraints in evolutionary explanation. The received view of developmental constraints sees them as an internalist concept that tend to be shared across related species as opposed to selective pressures that are not. Thus, to the extent that constraints can explain anything, they can better explain similarity across species, while natural selection is better able to explain their differences. I challenge both of these aspects (...) of the received view and propose a hierarchical view of constraints. (shrink)

Understanding the operation and evolution of gene regulation networks is critical to understanding ontogeny and evolution. According to Stuart Kauffman's view, (1) each cell type cycles through its own repeated pattern of gene expression, (2) the order of ontogeny is dependent on these cycles being short, and (3) evolution is possible because these cycles mutate gradually. This view of gene regulation reflects Kauffman's view that ontogeny is fundamentally the process of cells repeating cycles of activity. I criticize Kauffman's view of (...) gene regulation networks and offer the connectionist theory of gene regulation as an alternative. On this view, the generic order of gene regulation mechanisms is due to the qualitatively consistent way that one gene product influences the expression of another. This allows networks to be stable and evolve to regulate accurately, allowing cells to react appropriately to their microenvironments, due to design by natural selection. Introduction Kauffman's Model of Gene Regulation Explaining the Order of Kauffman's K = 2 Networks The Importance and Relevance of Kauffman's Explanations of the Order of Gene Regulation Additional Orderly Facts of Transcription The Order of Network Accuracy The Accuracy of Connectionist Networks The Evolvability of Gene Regulation Networks Laws of Structure CiteULike Connotea Del.icio.us What's this? (shrink)

I show that gene regulation networks are qualitatively consistent and therefore sufficiently similar to linearly seperable connectionist networks to warrant that the connectionist framework be applied to gene regulation. On this view, natural selection designs gene regulation networks to overcome the difficulty of development. I offer some general lessons about their evolvability that can be learned by examining the generic features of connectionist networks.

This contribution to the adaptationism debate elaborates the nature of constraints and their importance in evolutionary explanation and argues that the adaptationism debate should be limited to the issue of how to privilege causes in evolutionary explanation. I argue that adaptationist explanations are deeply conceptually dependent on developmental constraints, and explanations that appeal to constraints are dependant on the results of natural selection. I suggest these explanations should be integrated into the framework of historical causal explanation. Each strategy explicitly appeals (...) to some aspect of the evolutionary process, while implicitly appealing to others. Thus, adaptationists and anti-adaptationists can offer complementary causal explanations of the same explanandum. This eliminates much of the adaptationism debate and explains why its adversaries regularly agree with each other more than they would like. The adaptationism issue that remains is a species of the general issue of how to privilege causes in explanation. I show how a proposed solution to this general problem might be brought to bear on evolutionary explanations, and investigate some difficulties that might arise due to the nature of the evolutionary process. (shrink)