Collaborative Research: Disentangling biological and environmental drivers of diversification in the Andean flora

The tropical Andes of South America is one of the world’s richest biodiversity hotspots. This diversity likely evolved due to the complex environmental and geological history of this region. However, exactly how plant diversity arose from the combination of mountain uplift, the development of new habitats, and species interactions is unclear. This research aims to understand how these factors led to plant diversity in cloud forests and high-elevation grasslands. The researchers will develop new software to compare plant genomes to understand the ancestry of four groups of flowering plants in the Andes. The project will also result in new mathematical models to test the importance of different factors in shaping diversity in these plant groups. These new methods will have broad application to studies of biodiversity in the Andes and beyond. Additionally, this project aims to train the next generation of scientists in the study of biodiversity through a variety of interrelated activities, including: (1) a course for undergraduates to do guided genomic research; (2) collaborative training for students; and (3) computational training for diverse students. The project will first establish well-supported phylogenetic hypotheses for each of the four focal clades of Andean plants using low-coverage and targeted genome sequence data. Samples will be collected from Colombia as well as museums. This work highlights the importance of natural history collections in cutting-edge biological research, and new fieldwork will add to those collections. A component of the research will be to develop new approaches to address complexities common in plant genomes, including polyploidy and paralogy, that can affect estimates of evolutionary relationships. These methods will be made available through open-source software such that other researchers can easily estimate phylogenies and examine support for phylogenetic hypotheses using sequence data. Second, the project will develop new models that jointly infer the roles of dispersal and trait evolution in species diversification. These methods will be applied to phylogenomic, morphological, and distribution data collected for this project. These methods will also be made publicly available for widespread use. Finally, by comparing the roles of biogeographic and ecological processes in generating diversity in these clades, the research will address the generality or idiosyncrasy of the processes facilitating rapid radiation in tropical Andean plants. 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.