Dissertation Research: The Effects of Phenotypic Variation on Food Web Architecture and Ecosystem Fluxes: A Dual Tracer Isotope Approach

这项研究的主要目标是确定单一物种内的变异如何影响溪流食物网中的能量和材料的转移。这项拟议的研究将使用进化研究的模式系统--特里尼迪亚孔雀鱼(Poecilia Reticata)--来确定单个物种的两种表型如何影响溪流中的生态系统过程。特立尼达岛上的溪流出现在平行的分水岭上，与当地适应的孔雀鱼种群具有相似的环境梯度。在以前的研究中已经确定了两种表型：来自有捕食者的溪流的孔雀鱼和来自没有捕食者的溪流的孔雀鱼。这两种孔雀的表型可能会以独特的方式影响生态系统，因为它们的食物和食物的方式不同。这项研究使用重复实验来检验孔雀鱼的表型和资源可获得性如何影响生态系统。更好地理解物种内变异如何影响生态过程将提供对生态过程和进化过程之间相互作用的额外洞察，这可能是广泛和重要的。许多人熟悉孔雀鱼，因为它们在水族馆贸易中扮演着突出的角色，使它们成为一个可访问的系统，以交流关于进化生态学的科学研究。这项工作还将为土地利用变化如何改变河流生态系统的研究提供信息。

The primary goal of this study is to determine how variation within a single species can influence the transfer of energy and materials in stream food webs. The proposed research will use a model system for evolutionary studies, the Trinidadian guppy (Poecilia reticulata), to determine how two phenotypes of a single species can influence ecosystem processes in streams. Streams on the island of Trinidad occur in parallel watersheds that have similar environmental gradients with locally adapted populations of guppies. Two phenotypes have been established in previous studies: guppies from streams with predators, and guppies from streams without predators. These two guppy phenotypes are likely to influence the ecosystem in unique ways because of differences in how they feed and what they eat. This study uses a replicated experiment to examine how both guppy phenotype and resource availability influence ecosystems.A better understanding of how within-species variation affects ecological processes will provide additional insight into interactions between ecological and evolutionary processes, which may be widespread and significant. Many people are familiar with guppies because of their prominent role in the aquarium trade, making them an accessible system to communicate scientific research about evolutionary ecology. This work will also inform studies of how land use change alters stream ecosystems.