Caroline Amoroso, Ph.D

Title: Ecology and evolution of parasite avoidance behavior: a tale of lemurs, lockdown, and little worms

Abstract. Avoidance behavior represents a powerful first defense for hosts in their repertoire of strategies to fight parasites. Most research on avoidance behavior has asked how parasite avoidance trades off with other aspects of animals’ ecology, including predator avoidance or resource acquisition. This talk starts by using this approach to investigate how wild lemurs in a dry forest in Madagascar avoid parasite risk in their selection of water sources. The talk then takes initial steps in bridging the gap from this ecological perspective to an evolutionary one, in which the goal is to understand how ecological processes maintain host genetic variation in avoidance. Using a theoretical framework, the talk explores the importance of understanding the costs of avoidance, and the potential for avoidance to impact the evolution of other host defenses. To test the theory empirically, the model nematode host Caenorhabditis elegans and bacterial pathogen Serratia marcescens present an exciting opportunity to quantify natural genetic variation in avoidance and manipulate its evolutionary trajectory using artificial selection in the lab. The talk outlines preliminary and planned research projects that integrate theory with experiments in C. elegans, developing a tractable way forward for studying parasite avoidance behavior in an evolutionary context.