Competition for Biotic Resources and Coexistence in Variable Environments

竞争是塑造生态社区的核心力量。经典竞争理论预测，能够共存的物种数量不应超过有限供应的资源数量。然而，自然群落往往拥有大量物种，尽管资源数量通常很少，但供应有限。例如，一公顷巴拿马热带雨林可以养活18,000种甲虫。这么多物种怎么可能在不面临灭绝的情况下共存于自然界呢？生态学家提出了无数的假说来解释理论和数据之间的差异。这个项目将对其中一些假设进行实验测试。这项研究将审查资源可获得性随时间的变化的后果，以及跨空间资源可获得性变化对物种共存的影响。工作将在实验室微生物微宇宙中进行，其中包含以细菌为食的单细胞原生生物及其细菌资源。该项目的结果将帮助科学家了解维持自然群落物种多样性的机制。此外，该项目将通过培训研究生和本科生(包括未被充分代表的少数族裔学生)，为本科生生态课程提供案例研究，并促进K-12学生的科学学习，促进教育外展。

Competition is a central force shaping ecological communities. Classic competition theory predicts that the number of species that can coexist should be no more than the number of resources that are in limited supply. Natural communities, however, often harbor a large number of species, despite the typically small number of resources in limited supply. For example, one ha of Panamanian rainforest supports 18,000 species of beetle. How could such a large number of specie possibly coexist in nature without facing extinction? Ecologists have proposed a myriad of hypotheses explaining this discrepancy between theory and data. This project will experimentally test some of these hypotheses. The research will examine the consequence of changes in resource availability over time and the consequences of changes in resource availability across space for species coexistence. Work will be conducted in laboratory microbial microcosms containing bacteria-feeding single-celled protists and their bacterial resources. Results from this project will help scientists understand mechanisms of maintenance of species diversity in natural communities. Further, this project will contribute to educational outreach by training graduate and undergraduate students (including underrepresented minority students), providing case studies for undergraduate ecology courses, and facilitating science learning among K-12 students.