REU: Parasite Communities in the Wyoming Ground Squirrel

在过去的几年里，关于竞争的争论， 群落结构的一个主要决定因素 对生态文学的贡献。 经验工作， 提供明确数据支持的自然群落 这两个论点都不常见。 实验，现场和 实验室，提出将证明存在或不存在 寄生虫行会内部的竞争 结果将显示，如果 几个物种有可能占据“同一生态位”， 同时还研究与讨论 此外，还将收集以下方面的充分数据： 宿主与寄生虫的相互作用，以确定这种关系是否 寄生的或寄生的。 这项提案将检验这一假设 （1）怀俄明州地松鼠（Spermophilus elegans 球虫（Eimeria）协会是一个长期的产物， 共同进化的历史，“寄生虫”真的是 动物对宿主适应性的影响;（2） 寄生虫在宿主中不引起免疫应答，以及（3）存在 寄生虫种与宿主之间无生态位划分。 它 这些寄生虫已经进化到使用 资源，快速再生的肠道细胞 上皮，它们是逃亡物种的缩影。 的 建议将测试社区一级控制的缺乏， 使用地松鼠模型系统的“逃亡”物种， 他们的寄生虫。 这是第一个长期的实验研究 宿主-寄生虫相互作用的持续时间或与这样一个 自然群体中的大样本量。

Over the last few years the controversy about competition as a major determinant of community structure has made a variable contribution to the ecological literature. Empirical work in natural communities which provides unambiguous data to support either of the arguments is uncommon. The experiments, field and lab, which are proposed will demonstrate the existence or absence of competition within a guild of parasites. Results will show if it is possible for several species to occupy the "same niche" at the same time. In addition, sufficient data will be gathered on host parasite interactions to determine if the relationship is parasitic or commensal. This proposal will test the hypothesis that: (1) the Wyoming ground squirrel (Spermophilus elegans elegans)-Coccidia (Eimeria) association is the product of a long coevolutionary history and that the "parasites" are really commensals with animal effects on host fitness, (2) the parasites elicit no immune response in the host, and (3) there is no niche partitioning among parasite species with the host. It is proposed that these parasites have evolved to use ephermeral resources, the quickly regenerating cells of the intestinal epithelium, and they are the epitome of fugitive species. The proposal will test the lack of community-level controls on "fugitive" species using a model system of ground squirrels and their parasites. This is the first long-term experimental study on host-parasite interactions of this duration or with such a large sample size in a natural population.