NSF Postdoctoral Fellowship in Biology FY 2015

Walsh Jennifer L, Durham NH

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2015, Research Using Biological Collections. The fellowship supports a research and training plan for the Fellow to take transformative approaches to grand challenges in biology that employ biological collections in highly innovative ways. The title of the research plan for this fellowship to Jennifer Walsh is "Combining museum and contemporary data to understand mechanisms of speciation between two tidal marsh birds." The host institution for this fellowship is Cornell University, and the sponsoring scientist is Dr. Irby J. Lovette. Natural hybrid zones offer the opportunity to investigate evolution in action and the future of biodiversity, while providing insight into the mechanisms driving reproductive isolation between two interacting species. Comparison of temporally replicated data, in particular, provides valuable insight into how a hybrid zone is shifting or expanding in time and space. The fellowship research uses a temporally replicated approach to evaluate patterns in a hybrid zone between two tidal marsh endemics, the Saltmarsh and Nelson's sparrow. This hybrid zone has expanded approximately 160 km in less than a century; however, pure species boundaries appear to be maintained. Temporal comparisons provide new insight into the maintenance of genetically and morphologically pure populations in the face of rapid hybrid zone expansion and is of utmost importance in the northeastern U.S. to local and regional governmental and non-governmental groups concerned with conservation, as Saltmarsh and Nelson's sparrows are both high priority species in this area; the Saltmarsh Sparrow, in particular, is considered globally vulnerable to extinction. The approach combines the use of valuable archived biological collections and cutting edge genomic analyses of extant populations to document the dynamics between Nelson's and Saltmarsh sparrows over the past 125 years. Specimens come from several collections, including Cornell University, Delaware Museum of Natural History, Harvard Museum of Comparative Zoology, the University of Connecticut, the University of Maine, and the Canadian Museum of Nature. Given the vulnerability of Nelson's and Saltmarsh sparrows to habitat loss and degradation, a better understanding of temporal dynamics promises to aid the projection of future outcomes in this area as well as general understanding of hybrid zones. Training goals inchude gaining expertise in population genomics and in newly developed approaches to sequencing partial genomes from archived biological specimens. Educational and public outreach include sharing results of Saltmarsh and Nelson's sparrow interactions with the Saltmarsh Habitat and Avian Research Program, a regional, collaborative tidal-marsh bird monitoring and conservation initiative concerned with management plans for the species, and the very popular interactive websites of the Cornell Lab of Ornithology, e.g., All About Birds and All About Bird Biology.