Collaborative Research: Elucidating the Mechanisms of Coexistance in Communities of Ant-plant Mutualists

生态学的一个主要目标是了解促进竞争物种之间共存的因素。主要的假设机制是生境异质性，但其他机制包括资源可用性的时间波动、空间限制的扩散以及繁殖力、扩散和竞争力之间的权衡。只有少数这些机制已经被证明在该领域运作，同时评估多种机制的实验测试是罕见的。该研究将评估群落生态学中一个新兴模式系统中的替代共存机制——蚂蚁在被称为domatia的专门植物结构中竞争建立殖民地。三种蚂蚁占据了亚马逊树的domatia Tococa bullifera和Maieta guianensis。利用这一系统，非互斥机制可能促进蚂蚁共存，将通过实地观察、操纵实验和数学模型的组合进行测试。因为这个系统是由两个专家和一个通才在两个资源上共存组成的，我们的结果可以为生态群落专业化的演变提供独特的见解。该项目将为学生在学术生涯的多个阶段提供充分的机会，以发展研究、建模和指导技能。此外，合作PI所在的院校拥有大量少数族裔学生，这将使他们能够继续指导来自代表性不足群体的学生。最后，该项目将加强充满活力和富有成效的国际合作，并使美国学生获得在亚马逊生态系统工作的第一次经验。

A major goal of ecology is to understand the factors promoting coexistence amongcompeting species. Chief among the hypothesized mechanisms is habitatheterogeneity, but alternatives include temporal fluctuations in resource availability,spatially restricted dispersal, and tradeoffs among fecundity, dispersal, and competitiveability. Only a handful of these mechanisms have ever been shown to operate in thefield, and experimental tests simultaneously evaluating multiple mechanisms are rare.The proposed study will evaluate alternative coexistence mechanisms in an emergingmodel system in community ecology - ants that compete to establish colonies inspecialized plant structures known as domatia. Three species of ants colonize thedomatia of the Amazonian trees Tococa bullifera and Maieta guianensis. Using thissystem, non-mutually exclusive mechanisms that may promote ant coexistance will betested with a combination of field observations, manipulative experiments, andmathematical models. Because this system is composed of two specialists that coexistwith a generalist on two resources, our results could provide unique insights into theevolution of specialization in ecological communities. The project will provide ampleopportunities for students at multiple stages of their academic careers to developresearch, modeling, and mentorship skills. Furthermore, the collaborating PI's are atinstitutions with large minority enrollments, which will allow them to continue mentoringstudents from underrepresented groups. Finally, this project will strengthen a dynamicand productive international collaboration, and allow US students to gain their firstexperience working in Amazonian ecosystems.