Secondary metabolites are organic compounds produced by plants that are not essential in growth, development, or reproduction. While they are not strictly necessary to complete the plant life cycle, secondary metabolites play key roles in functions like defense against herbivory and the moderation of symbiotic relationships. Terpenes are a major class of secondary metabolites present in all plants, and this class is hypothesized to have diversified in response to specific plant-herbivore interactions. These complex interactions are further complicated by changes in abiotic conditions experienced seasonally. Herbivory is a major biotic interaction that plays out across broad temporal and spatial scales that vary dramatically in temperature regimes, both due to climate variation across geographic locations as well as the effect of seasonality. In addition, there is an emerging understanding that global climate change will continue to alter the temperature regimes of nearly every habitat on Earth over the coming centuries.Regardless of source, variating in temperature may influence herbivory, in particular via changes in the efficacy and impacts of plant defense chemistry. This study aims to characterize temperature-driven variation in the toxicological effects of several structural classes of terpenes in the model herbivore Vanessa cardui, the painted lady butterfly. We observed and increase in terpene toxicity at higher temperatures and an increase in development time as terpene concentration increased. Results obtained from this study yield insights into possible causes of seasonal variation in plant terpene production as well as inform effects of rising global temperatures on plant-insect interactions.

Thesis Completion




Thesis Chair/Advisor

Mason, Chase


Bachelor of Science (B.S.)


College of Sciences





Access Status

Open Access

Release Date