Tom's research explores themes of ecological and evolutionary genetics in natural populations. He is generally interested in phenotypic evolution. A current focus of the lab is the identification and characterization of genes responsible for drought-adaptive variation in Arabidopsis ecotypes collected from around the world. In addition, he has a long-standing interest in the ecology and evolution of animal-plant interactions, including projects focusing on pollination biology and herbivores in natural scarlet gilia (Ipomopsis agregata) populations.