NSF Postdoctoral Fellowship in Biology FY 2021: Does genomic recombination stabilize populations and enhance ecosystems?

Nadeau, Christopher Paul, Salem MA

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. Ecosystems provide invaluable services to humans such as maintaining water quality and reducing coastal flooding effects. A key rule of life is that ecosystems with more species often provide better and more consistent services. The same rule might also apply within species, where populations with a higher diversity of individuals – that is higher genetic diversity – are more stable and provide better ecosystem services. If this is true, managing communities of species to maintain high genetic diversity could provide significant benefits to humans. However, within a single species, sexual reproduction alters genetic diversity over time by producing offspring with new combinations of genes (a result of recombination). This project asks whether this circumstance breaks down the aforementioned rule of life by disrupting optimal states of genetic diversity. By answering this question, new insights will be made about how to appropriately manage genetic diversity across geographic regions that encompass multiple levels of biological organization. The Fellow will provide outreach activities associated with this work by involving members of underrepresented groups in research and training activities. This project will address how recombination at the intraspecific level alters predictions from interspecific theory, and therefore contributes to a cross-scale synthesis in biology. Specifically, interspecific theory predicts that communities with a mix of highly diverged species will have higher stability and function. Recombination at the intraspecific level could change this prediction because it can produce offspring with low fitness and thereby reduce stability and function (outbreeding-depression hypothesis). Conversely, recombination between highly diverged genotypes could increase genotypic diversity among offspring and thus increase stability and function (increased-diversity hypothesis). The Fellow will use genomics, lab-based breeding experiments, and field-based mesocosm experiments in a model system - Daphnia magna - to test how divergence and recombination interact to alter population stability and function. The Fellow will learn, apply, and advance genomic techniques for measuring the various forms of genetic divergence within species. The Fellow will also produce a Guide to Genetic Management for Conservation Practitioners, provide training and research exposure to two technicians from underrepresented communities in biology, and continue outreach to K-12 educators. 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.