STORZ, Shonna R.: Phylogenetic analysis of socially parasitic paper wasps (Hymenoptera: Vespidae)

Social parasites utilize workers of a host species to rear their own progeny. Emery’s rule argues that social parasites are most closely related to their hosts than to non-hosts. Researchers have investigated the evolutionary origin of social parasites in paper wasps using a phylogenetic framework and have found that social parasites form a monophyletic group and that multiple host species of a single parasite are sister taxa. My study uses sequence data from the known Polistes parasites, their hosts, additional non-host non-parasite species within the genus, as well as distantly related outgroup species to build parsimony and likelihood trees. My study is consistent with the findings that parasitic paper wasps form a monophyletic group. However, the results of my analysis suggest that parasites with multiple hosts do not necessarily parasitize sister species. These results suggest that close relatedness between a host and its parasite is not a necessary requirement for the association to exist. It also highlights the importance of applying rigorous phylogenetic methods and increased taxon sampling in constructing phylogenetic trees especially when addressing questions of evolutionary significance.