In my PhD thesis, I focus on the effects of intraspecific host genetic variation on symbioses. I'm investigating how host outcomes of these interactions could shift on a mutualism-parasitism spectrum. I study pea aphids and their bacterial partners to understand the role of genetic specificity in symbiosis. 

Pea aphids heritably associate with facultative symbionts that are not essential for survival, but provide context-dependent benefits. However, not all natural pea aphid populations associate with these symbionts and importantly there are non-random patterns of host-microbe specificity. The molecular mechanisms contributing to the maintenance of this specificity are not well-understood. For my first thesis project, I am exploring host and symbiont processes contributing to specificity in interactions. I'm developing meta-transcriptomics, flow cytometry assays, and single cell RNA sequencing to shed light on these mechanisms.

In my second thesis project, I'm exploring how host genetic background influences symbiont-mediated benefits. I'm studying bacterial symbionts that confer protection against a specialist fungal pathogen of aphids. I helped uncover a bacterial symbiont plasmid that is strongly correlated with anti-fungal protection. I'm now unraveling how host genetic variation influences these anti-fungal mechanisms across a variety of symbionts.