Dissertation Research: Ecological causes and consequences of intraspecific trait variation in an aquatic consumer

种群中的个体通常在体型、行为、形态和生理等特征上存在差异。生态学家直到最近才开始意识到这种性状变异对理解生态系统功能的重要性。推进这一领域的研究不仅需要我们了解物种内的性状变异如何影响更广泛的生态相互作用，还需要了解性状变异的起源及其生态背景如何决定种群内持续的性状变异的大小。该项目旨在澄清这种关系，以便能够预测性状变异发展的条件。这些基本问题将通过在人工池塘中建立蝌蚪种群的实验系统来检验。将进行两个实验来测试实验池塘群落的生态因素如何影响蝌蚪的形态和行为变化，并反过来受到蝌蚪形态和行为变化的影响。为了量化对蝌蚪性状变异的影响，将在池塘中操纵重要的生态变量，包括捕食、竞争和食物质量的空间变异。相反，蝌蚪性状变异的数量将通过实验改变，以确定变异本身如何影响池塘生态系统的生态组成部分。这项研究将深入了解生物多样性的价值，以及生物多样性丧失对生态系统功能的影响。结果将通过针对农民和其他参加宾夕法尼亚州立大学农业进步日的人的推广活动传播，并涉及当地惩教机构的囚犯，从而提高不同群体的科学素养。该项目的成果将通过制作吸引人且易于理解的视频进一步与公众分享，这些视频将提供给世界各地感兴趣的个人，并通过互联网在教室中使用。该项目将为几名本科生提供实地研究经验，并支持一名研究生的博士研究。

Individuals within populations often differ in traits such as size, behavior, morphology, and physiology. Ecologists have only recently begun realizing the importance of this trait variation to understanding the functioning of ecosystems. Advancing this area of research requires not only that we understand how trait variation within a species affects broader ecological interactions, but also how the origins of trait variation and their ecological context determines the magnitude of trait variation that is sustained within populations. This project seeks to clarify that relationship, so as to enable prediction of the conditions under which trait variation will develop. These fundamental issues will be tested using an experimental system of tadpole populations established within artificial ponds. Two experiments will be conducted to test how ecological factors in experimental pond communities affect, and are in turn affected by, morphological and behavioral variation in tadpoles. Important ecological variables, including predation, competition, and spatial variation in food quality, will be manipulated in the ponds in order to quantify the effect on tadpole trait variation. Conversely, the amount of trait variation in tadpoles will be experimentally altered in order to determine how the variation itself affects ecological components of the pond ecosystem. This research will provide insight into the value of biodiversity, and the consequences of biodiversity loss, for ecosystem functioning. Results will be disseminated through outreach activities targeted at farmers and others attending Penn State's Agriculture Progress Days, and involving inmates at a local correctional facility, thereby enhancing science literacy in diverse groups. Results of this project will be further shared with the public by creating engaging and easy-to-understand videos made available to interested individuals around the world and for use in classrooms via the Internet. This project will provide several undergraduates with field research experience, and support the doctoral research of a graduate student.