Evolution in parasite communities

The theoretical aspects of parasite community development are treated under four of the major models on community organization: Nonasymptotic, Asymptotic Equilibrium, Asymptotic Nonequilibrium, and Cospeciation Models. For each model, and for the phases within the Asymptotic Equilibrium Model, the predicted role of evolution in the past and present is described, particularly relating to competition between parasites. The tabulated assumptions of each model enable their identification in real communities, and the answers to five critical questions should provide a means of defining the model appropriate to each system. The study of competition and niche analysis is critical to developments in this field. That very different kinds of parasite communities exist and that different processes operate in each is recognized, but only further study will permit an evaluation of the role of evolution in general.