Variation in diversity of organisms across geographical regions has captured the attention of biologists for decades. Such patterns of diversity are driven by a combination of biogeography and ecological differences among species. The fish family Leuciscidae (minnows) presents an excellent opportunity to study the interplay of biogeography and ecology. Following migration to North America, these minnows have diversified extensively. This minnow diversity is often overlooked, even though species of Leuciscidae occur in freshwater streams across the continent. This research will test the origins and drivers of biodiversity in Leuciscidae. It will elucidate present-day biodiversity of these minnows, and will improve our general understanding of patterns of diversity across North America and globally. The project will train undergraduate and graduate students, and postdoctoral researchers. The research team will develop a public website on minnow diversity, will collaborate with grade school teachers to develop and implement lesson plans on biodiversity and museums, and will support outreach through traveling science museum programs.<br/><br/>An improved understanding of diversification of the family Leuciscidae requires a robust understanding of the evolutionary relationships, information on ecological differences among species, and data on species ranges. This project will reconstruct the phylogeny of Leuciscidae using new genome sequencing data, with broad sampling across the family. Researchers will use the phylogeny to determine timing and number of migrations to North America, and to investigate the biogeography of species and how species distributions have changed over time. They will compile ecological and morphological data, reconstruct how traits have evolved, and use comparative approaches to study adaptation and its role in diversification. This integrative approach using multiple lines of data will yield valuable insights into evolution of this important group of fishes.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.