Dissertation Research: The Influence of Immigration on Local Community Structure: Experimental Tests of Theory in Two Beetle Communities

识别构成当地社区的机制是社区生态学的一个基本目标。从历史上看，生态学家用局部过程来解释群落结构，但模棱两可的证据扩大了争论，包括区域过程在构建群落中的潜在重要性。虽然实验已被证明是解决生态学问题的关键，但到目前为止，理论和观察研究一直是用于检查区域过程影响的主要工具。我提出了一系列新颖的实验，以检验跨越本地和区域多样性控制范围的理论。本地过程、元人口竞争和中立社区理论对移民的影响做出了预测，这些理论在质量上是不同的，相互排斥的，并且在相同的移民实验中是可测试的。使用Tribolium面粉甲虫的实验室系统和Cecropia叶柄甲虫的野外系统，我将通过同时操纵迁移制度和相互作用强度（实验室），以及暴露于迁移和离殖民源的距离（野外）来实验验证这些理论。虽然最近发展的理论认为区域过程可以对群落结构产生主导作用，但如果要从区域过程的角度来理解群落生态学，这一理论必须首先得到实证的证实。

Identifying the mechanisms that structure local communities is a fundamental goal of communityecology. Historically, ecologists invoked local processes to explain community structure, butequivocal evidence has broadened debate to include the potential importance of regionalprocesses in structuring communities. Though experimentation has proven critical in resolvingissues in ecology, theoretical and observational studies have, thus far, been the primary tools usedto examine the effects of regional processes. I propose a series of novel experiments to testtheories that span the range between local and regional control of diversity. Local process,metapopulation competition, and neutral community theories make predictions about the effectsof immigration that are qualitatively different, mutually exclusive, and testable in the sameimmigration experiments. Using a laboratory system of Tribolium flour beetles and a field systemof Cecropia petiole beetles, I will experimentally test these theories by simultaneouslymanipulating immigration regime and interaction strength (lab), and exposure to immigration anddistance from colonization source (field). Though recently developed theory suggests regionalprocesses can have a dominant effect on community structure, the theory must first be confirmedempirically if community ecology is to gain insight from the regional process perspective.