Sean Mullen is a Professor of Biology and the interim Associate Dean of the Faculty for the Natural Sciences. Research in the Mullen lab is aimed at understanding the origin and maintenance of diversity at all levels of biological organization. Within this broader context, we are particularly interested in the link between divergent natural and sexual selection of adaptive traits (e.g. – mimicry in butterflies) and the origins of barriers to gene exchange between closely-related populations (i.e. – speciation).

Current projects in the lab have focused on addressing fundamental questions about patterns of biodiversity (e.g. – latitudinal gradients in species richness), and the role that life history evolution plays in driving adaptive diversification at both the larval and adult life-history stage among Neotropical Adelpha butterflies.
Students and postdocs in the lab employ a wide-variety of approaches, including: RAD-based phylogenetics and QTL-mapping, comparative and population genomic analyses of whole genome sequence data, RNA-seq, functional assays (e.g. -CRISPR/Cas9), as well as more traditional ecological techniques (e.g. – model-based predation experiments, behavioral and chemical assays of hostplant preference and performance).