show Abstracthide AbstractMilkweeds (Asclepias) are common and ecologically important perennial plants of North American grassland and forest ecosystems. They are the only host plants of the monarch butterfly, a species of significant conservation concern. Because milkweed species diversified over a short evolutionary time span, reconstructing their relationships is exceedingly difficult and requires examination of a large amount of data from across their genomes and powerful computational techniques. This research will contribute to the development of new methods for more accurately determining evolutionary relationships when many species have been formed in rapid succession. The results will have implications for better understanding the coevolution between milkweeds and monarch butterflies and the evolution of plant defense, as well as provide a robust evolutionary context for understanding the results of other scientific studies exploring aspects of plant reproduction, genome evolution, and other areas using milkweeds. The project will train postdoctoral fellows and graduate student in the latest phylogenetic and bioinformatics methods thereby training the next generation of phylogenetic biologists.