NSF Postdoctoral Fellowship in Biology FY 2016

Yitbarek Senay, Ann Arbor MI

Investigators

Abstract

Postdoctoral Fellow: Senay Yitbarek Proposal Number: 1612302 This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2016, Broadening Participation of Groups Under-represented in Biology. The fellowship supports a research and training plan that will increase the participation of groups underrepresented in biology. The title of the research plan for this fellowship to Senay Yitbarek is "Disease evolution: The consequences of spatial structure and co-infection on the evolution of virulence." The host institution for this fellowship is the University of California-Berkeley and the sponsoring scientist is Dr. Mike Boots. This research examines how infections of multiple parasites in hosts (co-infections) generates variation and drives disease dynamics at the population level. Classical work describing parasite effects on hosts has focused on single parasite systems. However, co-infections in hosts are ubiquitous in nature, and prior infection by a parasite can determine host response to subsequent invasions by parasites. Parasites that arrive early in a host may have an advantage over late-arriving parasites by occupying niches, or by inducing resistance mechanisms involving immune priming that elicits protection against further attacks. In addition, the spatial structure of hosts modulates the spread, impact and evolution of infectious diseases. The Fellow is testing the hypothesis that the spatial structure of host populations mediates co-infection and favors low parasite virulence. To address the ecological and epidemiological effects of co-infection on virulence evolution, the Fellow is focusing on interactions between the granulosis virus (PiGV) and the bacterial pathogen Bacillus thuringiensis (Bt) in the insect host population of Plodia interpunctella. This well-established infectious disease model system is ideally suited for experimentally evolving hosts and parasites and for examining the evolution of virulence of multiple infections. The Fellow is developing spatially explicit mathematical models of disease transmission involving co-infections from different parasite species, to predict parasite virulence. The Fellow is receiving training and mentoring in developing theoretical models of evolution, especially as applied to real world problems such as the role of co-evolution in infectious disease dynamics. In an era of increasing global contact networks that promote the spread of novel parasites and emerging infectious diseases, these skills will allow the Fellow to inform policy makers responsible for managing disease risk. The Fellow is partnering with the Biology Scholars Program at UC-Berkeley to mentor underrepresented students, by guiding them in developing independent research projects in host-parasite ecology. In addition, the Fellow is developing short-courses to expose students to hands-on field activities in evolutionary ecology, using inquiry-based learning. These activities increase the participation of underrepresented students in ecology and evolutionary biology, fields that have traditionally lacked diversity.