In addition to maintaining populations of mites (Tetranychus spp.) and cultures of TSWV (Tomato Spotted Wilt Virus), my research work concerns running of selection experiments between parasites with different interaction mechanisms (competition and facilitation). These interactions may influence the evolution of virulence of the different study parasites. This will be tested in assays following evolution. The research work involves two species of mites (Tetranychus spp.) and the TSWV to study the evolution of virulence when these organisms evolve or co-evolve in the presence of another species of parasite.