Abstract
We will test developments within the geographic mosaic theory of coevolution that have led to predictions regarding the maintenance of biodiversity in hosts and parasite where dispersal dynamics of the interacting species occur on different relative spatial and temporal scales. For this, we need to establish the ratio of parasite to host migration and determine the genetic nature of resistance and virulence traits involved in the interaction. This will be done in a well-characterised host metapopulation, Silene dioica in Skeppsvik Archipelago, and three parasites. The sterilising anther-smut fungus, Microbotryum violaceum disperses on a similar spatial scale to its host, but invades host populations long after they are formed. Caryocolum viscariella, a parasitic moth, and Delia criniventris, a root maggot, destroy flowering shoots, may disperse slightly further than their hosts, but enter host populations shortly after they are formed. Our goal is to show that the genetic mosaics created by colonisation and gene flow dynamics of both host and parasites maintain a high level of genetic variation in parasite selected traits. The results will be used to support the argument that preserving/restoring networks of coevolving populations, including the parasites, is a more efficient way to maintain the evolutionary processes that are important to biodiversity and future evolutionary response.
Sweden