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

捕食者对猎物的直接消耗具有强大的生态和进化后果。然而，捕食者也有间接的影响。捕食者通常会降低猎物的密度，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，资源的可获得性塑造了生活史的进化(即成熟年龄、后代数量)。这项研究调查了特立尼达岛自然鱼类种群中捕食者的间接影响和猎物进化之间的潜在联系。位于不同的群落中，有竞争者和捕食者。由于种群密度和可能的食物的巨大变化与其他鱼类物种的存在相关，因此溪流的进化可能受到这些种间相互作用的直接和间接影响。这个项目将提高我们对进化如何在自然界中发挥作用的理解，特别是关于进化过程和生态过程之间的相互作用。具体的主题是生活史的演变，但这项研究的概括性更深远。这是因为在自然环境中的进化几乎总是涉及生物体在相互作用时的直接影响，但也包括它们对群落其余部分的间接影响，由此产生的进化变化最终由这些直接和间接影响之间的相互作用决定。这项工作也为本科生提供了大量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.