Adam Pepi is a current grad student in my lab. Patrick Grof-Tisza and Eric LoPresti are postdocs at other universities who are currently working in my lab. Coming soon: Danielle Rutkowski.
I’m interested broadly in population & community ecology, especially as they are affected by global climate change. While population ecology is a relatively mature discipline, we still do not understand the variation in dynamics that can be present even in different populations of a singles species. This variation among different populations may provide insights into how the species will react to changing climate.
My dissertation research at UC Davis focuses on the population ecology of the Ranchman’s tiger moth (Arctia virginalis):
- variation in its dynamics across space,
- the relative contributions of abiotic & biotic as well as top-down & bottom-up drivers in different locales, and
- indirect & direct effects of environmental warming on dynamics and interactions.
My research concerns how trophic forces structure the spatial distribution of populations and how these forces vary across spatial and temporal scales. Additionally, I seek to understand how organismal movement may interact with these structuring forces to influence within-patch dynamics. My study system consists of a generalist herbivore, a tiger moth (Platyprepia virginalis; Lepidoptera: Arctiidae), and its primary parasitoids and host plants. A twenty-plus year data set exists for the population of P. virginalis within the Bodega Marine Reserve on the northern California coast. Combining this historical data set with my ongoing manipulative field experiments and observational studies provides a rare opportunity to identify and possibly explain long-term patterns and gives context to more recent population trends.
I am currently studying the ecological consequences and evolutionary patterns of chemical defenses excreted by plants. A staggering variety of plants have excretory structures that may have defensive roles, including salt glands, salt bladders, epicuticular waxes, extra-floral nectaries, and resin glands. While external plant defenses are chemically diverse and have different modes of action, their interactions with other organisms may make them a distinct group from the more widely studied internal chemical defenses. I study chenopods, a diverse and extremely widespread family of plants with a unique excretory system (“salt bladders”) that has defensive roles. Members of this family include quinoa, spinach, beets, and the saltbushes, as well as some noxious weeds such as pigweed and tumbleweeds.