A theory and a mathematical model for the evolution of single and multiple host behavior in a parasite-host system (Maculinea-Myrmica)

We present a theory for the evolution of multiple host use in the parasite-host system Maculinea-Myrmica. A mathematical model supporting the theory is presented and some results from simulations discussed. Qualitative predictions from simulations of the model are tested using empirical data on the chemical profiles of population of hosts and parasites. The results show that increased similarity between the profiles of the host species is correlated with multiple host use, as predicted by the model. The model provides a theoretical framework which is totally coherent with: (1) patterns of host use by the Maculinea cuckoo species and (2) phylogenetic studies that suggest host shift during the evolutionary history of the species. The results also suggest that it might be possible to create a method to infer host use by the parasite species, based only on cuticular hydrocarbon profiles. Such method would be important for conservation measures.