This project investigates how the biodiversity of one of the world's most important groups of freshwater fishes evolved. Containing tetras, piranhas and many other popular aquarium fishes, order Characiformes represents one of the most diverse groups of fishes on the planet, but some of its families include species of many varying shapes, sizes and diets, while others include numerous species with similar habitats, food sources and anatomies. Why are some groups more diverse than others? How do its many species fit together on their family tree? How do a dozen or more ecologically similar species coexist in a single river? This project will tackle such questions by assembling a comprehensive tree-of-life for the very diverse characiform superfamily Anostomoidea (headstanders and relatives) using traditional DNA analysis, study of skeletal anatomy, and a new genomic approach. Then, that tree-of-life will serve as a framework with which to investigate the evolution of anatomical and ecological biodiversity.
Overall, this project synthesizes the expertise and genetic resources of two countries to forge an enduring international collaboration and reconstruct the evolutionary history of some of the most intriguing South American fishes with precision and detail that would be impossible if the labs were to work alone. It draws on diverse human capital in the US and in Brazil, including the author of previous evolutionary studies on these fishes, one of Brazil?s leading fish geneticists, an expert on taxonomy, a leader in genomics and macroevolution, and students in both countries. Other broader impacts include the involvement of undergraduate students in research and outreach, development of a DNA-barcode library and interactive online identification key, sponsorship of graduate students at a training workshop and active participation in the Smithsonian's "The Scientist is In" program, which brings the public into direct contact with museum-affiliated researchers and specimens.