DISSERTATION RESEARCH: Evaluation of the direct and indirect effects of predators on life history evolution in a Trinidadian killifish

捕食者直接吃掉猎物对生态和进化有重大影响。然而，捕食者也有间接影响。捕食者经常降低猎物密度，这间接增加了幸存个体的食物供应。这些生态相互作用也可能影响进化变化，因为理论框架表明，资源的可用性决定了生命史的进化（即成熟年龄、后代数量）。本研究调查了特立尼达岛天然鱼类种群中捕食者的间接影响与猎物进化之间的潜在联系。特立尼达鳉，hartii Rivulus分布在不同的竞争对手和捕食者群体中。由于种群密度和可能的食物的巨大变化与其他鱼类的存在有关，因此这些种间相互作用的直接和间接影响很可能影响了河流的进化。这个项目将提高我们对自然界中进化如何运作的理解，特别是关于进化和生态过程之间的相互作用。具体的主题是生命史进化，但这项研究的概括性更为深远。这是因为自然环境下的进化几乎总是包括生物相互作用时的直接影响，但也包括它们对群落其他部分的间接影响，最终的进化变化是由这些直接和间接影响之间的相互作用决定的。这项工作也为本科生提供了许多获得研究经验的机会。

The direct consumption of prey by predators has potent ecological and evolutionary consequences. Yet, predators also have indirect effects. Predators often decrease prey density which indirectly increases food availability to surviving individuals. These ecological interactions could also influence evolutionary change because theoretical frameworks suggest that resource availability shapes the evolution of life histories (i.e. age at maturity, number of offspring). This research investigates the potential link between the indirect effects of predators and the evolution of prey in natural fish populations on the island of Trinidad. Trinidadian killifish, Rivulus hartii are located in communities that differ in the presence of competitors and predators. Since large changes in population density and likely food are correlated with the presence of additional fish species, evolution in Rivulus is likely influenced by the direct and indirect effects of these interspecific interactions. This project will improve our understanding for how evolution works in nature, particularly with respect to interactions between evolutionary and ecological processes. The specific topic is life history evolution, but the generalities of this research are more far-reaching. This is because evolution in a natural setting will almost always involve the direct effects of organisms as they interact, but also their indirect consequences on the rest of the community, with resultant evolutionary change ultimately determined by interactions between these direct and indirect effects. This work also offers numerous opportunities for undergraduates to obtain research experience.