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

摘要：利用毛滴菌（真菌）幼虫拟蝇科（水生蝇）模型，PI提出在野外和实验室条件下确定这些共生关系的性质是否经常从一种状态转变为另一种状态。因此，寄生、共生和互惠只是在特定的内在（真菌感染强度、寄主物种）和外在（环境）条件下对物种相互作用的暂时描述。他们认为，这种共生关系的特定状态可以通过宿主（共生组织中较大的成员）和共生体（共生组织中较小的成员）所处的环境条件来预测。他们还将研究跨景观共生的动态。这将为在大空间尺度上评估共生相互作用的性质提供独特的机会，从而确定地理结构在形成共生关联方面的重要性，并为将影响每种寄主物种分布的因素与影响每种毛滴虫物种分布的因素分离开来提供机会。

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.