Jackie’s research explores the evolution of ecological interactions in arthropods. The association of changes in these interactions with formation of new species has been a particular interest. Taxa have included phoretic mites and their beetle hosts, herbivorous moths and flies and their host plants and enemies, and damselflies and their biotic and abiotic environments. Ongoing projects include: (1) the evolution of host plant association in Hawaiian tephritids; (2) the evolution of body color and color dimorphisms in Hawaiian damselflies; and (3) the evolution of unicoloniality in North American Formica ant species. Jackie has also been the director of Grinnell’s Conard Environmental Research Area, where he has integrated long-term research on fire effects in prairie and woodland ecosystems into undergraduate biology classes.