Geographic Structure of Coevolving Insect/Plant Interactions

University Of California-Santa Cruz, Santa Cruz CA

Investigators

Abstract

0073911 Thompson This project will investigate how coevolution shapes the interactions between insects and plants across broad geographic landscapes. A major current challenge in ecological research is to understand how ongoing coevolution proceeds as interacting species experience different selection pressures in different communities (co-evolutionary hotspots). The combined ecological, geographic, and phylogenetic evidence allows the opportunity to use the interactions between the moth Greya politella and its host plants to address these central questions on co-evolutionary processes. The moths are locally host specific pollinating seed parasites, and the interaction between the moths and their host plants occurs across a wide range of habitats in western North America. Three objectives will be addressed in this study. The first objective is to determine whether the differences in outcome among communities are stable over time, and the second objective will assess whether the geographic patterns in outcome result from gene flow among populations in different communities. The third objective will be to evaluate how the differences in the interaction between the mutualistic and antagonistic hotspots identified during previous work contribute to the different ecological outcomes. Together, the results of these three objectives will aid in the development of the theory of coevolution and the organization of biodiversity. They will address how selection mosaics and co-evolutionary hotspots shape species interactions across geographic landscapes under different ecological conditions. Overall, the results will therefore contribute to our understanding of the geographic scale at which interspecific interactions diversity and the ways in which coevolution links taxa among communities.