The first major goal of my research is to explore the roles played by plant chemistry in the ecology and evolution of insect/host-plant associations.  This work focuses on the swallowtail butterflies (family Papilionidae) for almost all of which the host-plants are known worldwide.  Work in my laboratory and in Japan has identified the major categories of compounds used by swallowtails as oviposition stimulants.  Recently, we have established that responses to these compounds are inherited and not changed by experience (Heinz and Feeny, 2005).  Meanwhile, Felix Sperling (Univ. of Alberta), continuing his Ph.D. research done at Cornell, has established rigorous phylogenies for the Papilionidae.  We are thus ready to undertake phylogenetic analyses of chemoreception in this family as a basis for determining the roles of particular compounds as facilitators or constraints on host-range expansion and host shifts.  We have also recently shown for the first time that naturally-occurring host shifts are facilitated by the shared content of oviposition stimulants in ancestral and novel host plants (Murphy and Feeny, in press).  The second major goal of my research is to understand the ecological and historical factors that lead to different patterns of chemical defense by plants against attack by insects and other taxa.  I am currently exploring the variation in trade-offs between defense against insects and escape from discovery through disruption of chemical recognition.