Do parasites track the local environmental adaptation of their hosts?

Parasite-host interactions are among the most important ecological relationships. These relationships are further complicated if a parasite spends some of its life cycle outside the host and thus must survive under multiple environmental conditions inside and outside the host. Thus, parasitoids must be able to adapt as its host changes to fit its environment. This project focuses on determining the relationship between the desiccation resistance of the fly host Rhagoletis zephyria and the parasitoid wasps attacking it. Collected samples from across Washington state underwent a controlled desiccation treatment before being frozen for analysis. Frozen samples were dissected to determine parasitization rate among different locations. Parasitized samples were smaller overall in comparison to unparasitized samples. The samples also exhibited a strong positive correlation between fly and parasitoid desiccation resistance. Additionally, some parasitized samples underwent PCR analysis to determine the species of parasitoids present and attempt to connect this to patterns in desiccation resistance. So far, all samples were identified as a species of Utetes wasps, and more samples are needed to examine parasitoid species-species patterns.