Evolutionary Novelty

  • The problem of explaining novelty involves understanding how developmental systems are transformed in order to generate new ranges of variation through evolutionary time.
  • Some have advanced an argument for the physico-genetic origination of novelties that claims major morphological characteristics of metazoans originated from physical forces—diffusion, viscoelasticity, phase separation—operating on soft condensed materials early in evolution (e.g., Newman et al. 2006; Newman 2012). Generic properties of cells and tissues would interact with environmental forces to yield basic morphologies with minimal developmental genetic machinery. These forms would then be stabilized via genetic assimilation, becoming more robust in each generation, as we now observe experimentally.
  • This contrasts with developmental genetic explanations that appeal to the origination of new patterns of gene expression, especialy the emergence of networks of expression among regulatory genes, to account for the origin of new traits in the history of life (Erwin and Davidson 2006; Wagner 2014). “The evolution of new morphological features is due predominantly to modifications of spatial patterns of gene expression” (Gompel et al. 2005); “novelty requires the evolution of a new gene regulatory network” (Wagner and Lynch 2010).
  • This workshop addresses research questions such as: What aspects of evolutionary novelty are explained genetically? generically? What are the best examples of each type of explanation in isolation? Are there examples of integrated explanations involving genetic and generic approaches? If so, what are their characteristics? Are they successful? What empirical, theoretical, and conceptual barriers exist to integrating genetic and generic explanations of evolutionary novelty? What conflicting assumptions exist among different explanatory models?
  • The complete reading list and schedule of discussion from the workshop are now available here.

Suggested Readings

Davidson, E.H., and D.H. Erwin. 2006. Gene regulatory networks and the evolution of animal body plans. Science 311:796-800.

Engineering the Cambrian explosion: the earliest bioturbators as ecosystem engineers

Herringshaw, L.G., R.H.T. Callow, and D. McIlroy. 2017. Engineering the Cambrian explosion: the earliest bioturbators as ecosystem engineers. In: Brasier, A.T., D. McIlroy, and N. McLoughlin (eds) Earth System Evolution and Early Life. Geological Society, London, Special Publications, 448.18.

Newman, S.A. 2012. Physico-genetic determinants in the evolution of development. Science 338:217-219.

Newman, S.A., G. Forgacs, and G.B. Müller. 2006. Before programs: The physical origination of multicellular forms. International Journal of Developmental Biology 50:289-299.

Homology, Genes and Evolutionary Innovation

Wagner, Günter P. 2014. Homology, Genes and Evolutionary Innovation. Princeton NJ: Princeton University Press.