NSF Postdoctoral Fellowship in Biology FY 2021: What is the predictability of hybrid genome evolution across ecological contexts?

Fraik, Alexandra Kaye, Pullman WA

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2021, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the fellow that will contribute to the area of Rules of Life in innovative ways. Hybridization has been of long-standing interest to evolutionary biologists to understand how species interactions at the genetic level affect variation. Studying hybridization can provide valuable data on the genetic basis of traits of interest, and how new species evolve. Hybridization can occur naturally or as a consequence of human activities. This project will investigate how hybridization among natural and human-induced hybridizing Oncorhynchus trout species affects these species phenotypes. Throughout the Pacific Northwest, O. c. clarkii (coastal cutthroat trout) and O. mykiss (Steelhead) are ecologically and culturally significant trout species that hybridize, making them ideal species for this research. This work will be crucial to furthering scientific understanding of how the environment influences hybrid genome evolution and how predictable it is. The proposed NSF PRFB project builds on previous work to address a major gap in evolutionary biology research: how do hybrid genomes evolve? This research will evaluate the Rules of Life that govern how hybridization affects species’ adaptation and evolution, specifically how ecological context impacts genome evolution. Genomic and phenotypic data from experimental, lab-produced crosses of two trout species will be used to (1) investigate how hybridization impacts the chromosomal and genomic landscape of hybrids. Paired life-history data from hybrid crosses will (2) elucidate the fitness and phenotypic effects of hybridization. Finally, genomic data produced from natural populations will (3) demonstrate if parallel signals of genomic introgression are detected across natural and anthropogenically hybridizing populations. The computational methods developed for diagnosing the ancestry of tracts of genomic introgression, quantifying gene flow, and estimating timing of hybridization events in trout species can be applied across taxa. Research on the fitness and phenotypic consequences of hybridization will provide candidates for the genetic basis of hybrid fitness and phenotypes (e.g., genomic incompatibilities) currently lacking in hybridization literature. The PI will also mentor high school students from underrepresented communities in computational genomic projects, analyzing other hybrid genomic data sets. The PI and students will then co-present the findings from this research to conservation practitioners from tribal, non-profit and governmental institutions working on these hybridizing taxa in a workshop. This work will expand the computational genomic research skills of this PI, furthering her professional development for a career as an evolutionary geneticist for a top research institute. 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.