Disease dynamics in natural populations -- We continue annual surveys of several diseased populations. In some populations, we permanently tag all host individuals and collect detailed demographic data on births, deaths, and anther smut transmission. Samples of the anther smut fungus and the host species are also collected over time to be assayed for changes in population genetic structure. The annual census of anther smut disease on Silene latifolia in the region of Mountain Lake Biological Station is now in its fifteenth year under direction by Janis Antonovics. The data is being used to model the regional (i.e. metapopulation) dynamics of the disease.