NSF Postdoctoral Fellowship in Biology: The Roles of Gene Flow and Local Adaptation in Driving Fitness in a Genetically Depauperate Fish

Sparks, Morgan, West Lafayette IN

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2022, 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. This research addresses how isolated populations with low genetic diversity persist with focus on a subspecies of cutthroat trout: the greenback cutthroat. The greenback cutthroat, despite being Colorado’s state fish, was nearly extirpated and has been reduced to a single surviving population and a handful of reintroduced populations founded from that one population. This project seeks to compare genetic diversity between greenback cutthroat and a close relative at the landscape and population levels and then link those data with the ability for recovery populations in new habitats. The project leverages a past experiment in which the two subspecies were crossed to identify genomic features that contribute to fitness and boost the genetic diversity of greenback cutthroat without swamping the genetic features that are specific to the subspecies. The project will also bring these methods into the classroom at a local minority serving college to help train students in these cutting-edge technologies. The goal of this project is to link the genetic basis of phenotypic traits to their interaction with the environment for a genetically depauperate and isolated fish. This research will provide a predictive framework in which genomic features identified with whole-genome sequencing at three ecological and demographic scales are linked to individual fitness. First, it will assess standing genetic variation in two subspecies, the greenback and the closely related Colorado River cutthroat trout, and identify loci correlated with key environmental features using genetic-environmental analyses. It will then focus on recently reintroduced populations to measure how genetic diversity at introduction predicts the populations persistence via phenotypic plasticity or rapid adaptation. Lastly, genomic data from the two subspecies and their hybrids will be used to identify loci associated with inbreeding load and negative fitness in greenback cutthroat. These data will inform how genetic variation and environmental attributes manifest as individual fitness and the relative ability of each subspecies to adapt to changing conditions as a function of genetic diversity. Finally, the Fellow will lead both field and bench modules at a local, minority serving institution with the goal of introducing skills beneficial to career development and in pursuit of advanced degrees in STEM. 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.