He is broadly interested in the genetic basis of adaptation. As part of the group focused on the Evolutionary and Developmental Genetics of Butterflies and Moths, his experimental work with butterflies is primarily centered on the developmental genetics of wing patterning, with a focus on the morphogenetic mechanisms that create positional information on the wing. Butterfly wings, especially in Heliconius, are a crucible of evolutionary wizardry that provide an unique opportunity to study how phenotypes are tinkered over time. He has been working extensively with Bob Reed to characterize the developmental architecture of pattern variation, with a particular focus on the optix and WntA genes.