Cuvierian Functionalism

Abstract

The rise of evolutionary-developmental biology (evo-devo) is often claimed to mark the return of typological and/or structuralist thinking to evolutionary biology. Proponents of such claims point to evo-devo's emphasis on the deep conservation of animal body plans. Deep conservation requires long-term evolutionary stasis, which is difficult to explain in a Darwinian functionalist framework. Evo-devo biologists must therefore rely on other argumentative strategies to explain deep conservation. I argue, however, that their explanations are not typological or structuralist. Rather, they are Cuvierian functionalist: they recapitulate, in modified form, an argument developed by Georges Cuvier in the nineteenth century. Cuvierian functionalism is distinct from but complementary to Darwinian functionalism. Moreover, Cuvierian functionalism is immune to the traditional objections to typological thinking. Keywords cuvierian functionalism • evo-devo • typology • population thinking • Cuvier, Georges • gene regulatory networks • deep conservationCuvier believed that the radically different organizations of the four embranchements could not change from one to another without a fatal loss of integrated function during the transition. This argument is still a forceful one. -Rudolf Raff (1996, 6)

An account of conserved functions and how biologists use them to integrate cell and evolutionary biology

“…Future work could profitably expand on the importance of phylogeny for comparative research on biological function, for example in interdisciplinary fields such as bioinformatics, evolutionary development (Love 2017;Novick 2019), and evolutionary cell biology (Lynch et al 2014). We have noted already how conserved mechanisms, sequences, and other traits are central to evolutionary developmental explanations, and our analysis contributes to showing how biological categories such as body plans may be consistent with evolutionary theory (Novick 2019).…”

“…Future work could profitably expand on the importance of phylogeny for comparative research on biological function, for example in interdisciplinary fields such as bioinformatics, evolutionary development (Love 2017;Novick 2019), and evolutionary cell biology (Lynch et al 2014). We have noted already how conserved mechanisms, sequences, and other traits are central to evolutionary developmental explanations, and our analysis contributes to showing how biological categories such as body plans may be consistent with evolutionary theory (Novick 2019). The iterative use of molecular sequence alignments and functional inference we described can also illuminate how the emerging field of evolutionary cell biology combines historical and experimental methods to understand key events in the history of the eukaryotic cell (O'Malley et al 2019).…”