March 12th Seminar
This week’s seminar will be given by Charles Stone, a PhD student working with Dr. Janice Moore. There is a slight change of venue, as a faculty meeting has been scheduled in the room we normally use, so for this week – and this week only – please come to Yates 208. Here’s a title and brief abstract for Charles’ talk:
Does size matter? Fitness, larval size, and strange behavior related to the Acanthocephalan parasite Leptorhynchoides thecatus
Abstract: Modification of host behavior by parasites has been documented in a large variety of parasite systems. To understand how these phenomena evolve and operate, scientists have developed models and theoretical frameworks. Much of this literature explicitly assumes that there is a cost to a parasite when it actively changes host behavior, despite the fact that no study has demonstrated such a cost. The parasite Leptorhynchoides thecatus (Acanthocephala) presents an opportunity to investigate such a cost. Smaller larval cystacanths are less likely to survive transmission to the final host and establish as adults. Because transmission and establishment success are essential components of fitness, parasite larval size provides an important potential link to a fitness cost if behavioral modification is related to larval size. In this study, behavioral changes were demonstrated in a series of three behavioral tests on the crustacean intermediate host, Hyalella azteca (Amphipoda). Behavioral scores compared between infected and uninfected hosts show significant differences in behavior between groups. When infected amphipod behavior was considered in relation to parasite volume, none of the behaviors showed a strong influence of larval size. These results may be explained by a number of factors, which will be highlighted for future directions for this research.