Towards a standard model for teaching the process of biological evolution

James G DuBose, Levi T. Morran

Evolution is widely considered to be one of the cornerstones of the biological sciences. Despite this importance, the process of biological evolution remains widely misunderstood among students, illustrating that evolution education is in need of an educational synthesis. The current paradigm for teaching the evolutionary process revolves around using population genetics models to illustrate the evolutionary change. While this convention describes the consequences of evolutionary changes, it conflates these consequences with the actual process of biological evolution. In addition to increased cognitive load, the pedagogical cost of this conflation is general misconceptions about the drivers of evolutionary change that at best create an overly simplistic view and at worst hinder understanding of the evolutionary process. To help address this issue, here we suggest evolution education should focus on trait-based models of evolution, and propose that Fisher's geometric model may provide a more useful model for centering education. We start by describing Fisher's geometric model and show how it can be used to effectively illustrate the fundamental evolutionary process (mutation, drift, selection, and migration/gene flow). We then mathematically show how Fisher's geometric model generalizes several widely used models in evolutionary biology, as well as how it can be connected to conventional population genetics. We conclude that future work should focus on empirically evaluating the efficacy of teaching Fisher's geometric model in the classroom.