Understanding what drives the evolution of new species is a central question in biology. Groups of species that have recently evolved provide a good system for trying to understand the genetic changes that led to establishment of new species. This research combines the fields of genomics, developmental biology, ecology, and physiology to examine a new lineage of flowering plants in Hawaiʻi in the genus Bidens (family Asteraceae). The project will generate new genome assemblies and experimentally identify the genetic and developmental changes responsible for leaf, fruit/seed, and flower evolution in this group of species. This project will also provide training in inter-disciplinary evolutionary concepts and approaches for undergraduates, graduate students, and postdoctoral researchers, including those from underrepresented groups; improving the scientific workforce in the United States by preparing them to strongly contribute to scientific research, education, and/or technological advancements. This project will use newly developed genome sequencing methods to infer the broader evolutionary history of Polynesian Island Bidens, along with continental relatives. The updated understanding of how Bidens reached remote Pacific islands and diversified will provide the backbone for comparative evolutionary genomics of our six target species (three Hawaiian endemics and three continental). Comparing these genome sequences and differences in gene expression will allow us to identi