Morphology via Adaptive Mutations in Evolutionary Biology

Biologists in the tradition of Development Systems Theorists (DST) and Evodevo challenge the neo-Darwinian focus on genes as the sole agency defining development, as well as the inflationary claims of evolutionary psychologists. Instead, they argue for parity of explanation, treating genes, proteins, cells, and environment as forming a developmental system, where all factors contribute to what the phenotype would become. An important tenet of Evodevo biology is that adaptive mutations affecting morphology are more likely to occur in the cis-regulatory regions than in the protein-coding regions of genes. This argument rests on two claims: (1) the modular nature of cis-regulatory elements largely frees them from deleterious pleiotropic effects, and (2) a growing body of empirical evidence appears to support the predominant role of gene regulatory change in adaptation, especially morphological adaptation.