The Nature of Symbiotic Interactions in Running-Water Ecosystems: Trichomycete Fungi and Black Fly Hosts

University Of South Alabama, Mobile AL

Investigators

Abstract

McCreadie, John DEB 0075269 ABSTRACT: Using a Trichomycetes (fungus) larval Simuliidae (aquatic fly) model, the PI's propose to determine, under both field and laboratory conditions, if the nature of these symbiotic (co-existing in a close association) relationships frequently shift from state to state. Thus, parasitism, commensalism, and mutualism would be merely temporary descriptions of species interactions under particular sets of intrinsic (fungal infection intensity, host species) and extrinsic (environmental) conditions. They suggest that the particular state of this symbiotic relationship can be predicted by the environmental conditions under which the hosts (the larger member of a symbiotic association) and symbionts (the smaller member of a symbiotic association) are found. They will also examine the dynamics of symbiosis across landscapes. This will provide the unique opportunity to assess the nature of the symbiotic interactions over a large spatial scale, and hence determine the importance of geographic structure in shaping symbiotic associations and the opportunity to separate factors influencing the distribution of each host species from those influencing the distribution of each trichomycete species.