Parasite co-structure: broad and local scale approaches.

A co-structure study is a comparison of demographic and/or genetic structure between two or more species. Such a comparative analysis among a parasite and its host(s) or among multiple parasite species is useful to elucidate factors that shape genetic variation within and among parasite populations. I provide a brief review of how co-structure studies in parasite systems can be used to address ecological, evolutionary, and epidemiological questions. Subjects that can be addressed with parasite costructure studies range from broad-scale analyses that compare phylogeographical patterns to local scale analyses that examine among host transmission within a host population.