Scott Hotaling: Leveraging rad-sequencing to characterize recent divergence in an imperiled group of alpine invertebrates (Trichoptera: Rhyacophilidae) in Glacier National Park, Montana

Recently developed molecular methods such as restriction-site associated DNA sequencing (RADseq) have transformed the field of population genetics. It is now possible to rapidly collect thousands of genome-wide markers for non-model organisms to address pressing systematic, conservation, and evolutionary questions that have been previously intractable with fewer markers. The methodology for collecting RADseq data is no longer novel. And, with recent advances in next-generation sequencing technology (e.g. lower cost per base, longer read lengths) and improvements to existing protocols (e.g. more efficient bioinformatic pipelines, incorporation of additional size selection and shearing methods), a number of studies employing RADseq methods have been published. This advancement allows for a shift in research focus from questions of data collection to those of data utility. For instance, despite a growing body of literature, empirical tests of the power of RADseq data for delimiting recently diverged evolutionary lineages remain limited. And, from a conservation standpoint, there is a need to apply these newly developed genomic methods to systems in which time is in short supply such as understanding the nature of global warming impacts on cryptic biodiversity. But, a complete sea change in focus from methodological research to purely application would be premature as additional experimental design questions remain. For example, one fundamental systematic question remains largely unexplored, that is the degree to which orthologous markers can be simultaneously collected among divergent taxa. Here, I seek to utilize the power of RADseq data, coalescent-based species delimitation methods, and multi-population demographic model assessment to empirically address the utility of these data to identify young evolutionary lineages, add insight to the efficacy of RADseq for collection of orthologous loci across samples at varying taxonomic scales (within species, within a genus and between families) and simultaneously collect conservation genetic data for a group of imperiled taxa in a model system of climate change, Glacier National Park (GNP). I propose to carry out this research for a suite of endemic caddisflies of the genus, Rhyacophila, (Trichoptera: Rhyacophilidae) that reside in the alpine regions of GNP and are tightly linked to permanent glacial and snowfield meltwater, a rapidly disappearing resource in mountain ecosystems worldwide1.