LINKING VARIATION IN METABOLIC PROCESSES AS A KEY TO PREDICTION

生物和生态科学的一个主要目标是充分了解自然系统，以预测物种和种群如何应对快速变化的世界（即气候变化、栖息地丧失等）。一个种群在任何条件下都会增长、减少或完全消失，这取决于个体消耗资源（食物）、代谢利用食物以及最终繁殖的效率。然而，根据这些代谢过程做出准确的预测是很复杂的，因为每个物种都有不同的资源需求，而且一个物种内没有两个个体是完全相同的。相反，个体是不同的，这种差异，无论是在物种内部还是在物种之间，都是许多生态和进化过程的核心。因此，发展预测生物系统对不断变化的世界的反应的能力需要对变化有一个机械的理解。该项目的目标是通过检查具有常见资源需求谱的一系列物种的代谢背景下的变化来提高这种机制的理解。此外，这项工作利用了这组物种的独特生物学特性，允许控制和操纵个体繁殖，促进了个体消耗、代谢和繁殖变化之间机制联系的实验研究。这项研究的基础是现场测量和实验室实验的结合，使用成熟的和新开发的技术来量化这些联系。结果将是一个定量框架，以预测个体将如何对资源利用的变化作出生殖反应。由于个体繁殖与种群动态之间的密切联系，本研究将大大有助于预测个体使用多种资源的现实条件下的种群动态，并改进对当前和未来生态变化的反应的预测。更广泛的影响：这项研究将在三个方面对社会做出广泛的贡献。(1)制定K-12课程计划，以加强科学教育，为加强美国早期STEM教育的更广泛目标做出贡献。该项目的这一方面汇集了当地小学教师、南卡罗来纳大学（USC）小学教育本科学生和南加州大学科学教育中心的专家，根据拟议的科学调查制定了一系列课程计划。(2)改进评价生态系统食物网环节常用的化学工具（稳定同位素）。(3)提高对管理关注物种的认识。一些研究物种的管理受到关注，因为它们要么是全球许多地区有问题的入侵者，要么是由于过度捕捞减少了消费者的压力，目前数量正在增加，要么是各自栖息地中占主导地位但研究不足的消费者。这项研究将为这些物种的影响以及它们的生殖潜力提供重要信息。

A major goal of biological and ecological sciences is to understand natural systems well enough to predict how species and populations will respond to a rapidly changing world (i.e., climate change, habitat loss, etc.). A population under any conditions will grow, shrink, or disappear altogether depending on how efficiently individuals consume resources (food), utilize that food metabolically, and eventually reproduce. However, making accurate predictions based on these metabolic processes is complicated by the realities that each species has different resource requirements and that no two individuals within a species are exactly alike. Rather, individuals vary and this variation, both within and across species, is central to many ecological and evolutionary processes. Developing the ability to predict responses of biological systems to a changing world therefore requires a mechanistic understanding of variation. The goal of this project is to improve this mechanistic understanding by examining variation within a metabolic context across a range of species that have a spectrum of commonly-seen resource requirements. Further, the work capitalizes on a unique biological characteristic of this group of species that allows control and manipulation of individual reproduction, facilitating experimental study of the mechanistic links between variation in individual consumption, metabolism, and reproduction. The foundation this research is a combination of field measurements and laboratory experiments using both well-established and newly-developed techniques to quantify these links. The result will be a quantitative framework to predict how individuals will respond reproductively to changes in resource use. Because of the close link between individual reproduction and population dynamics, this research will contribute substantially to predictions in population dynamics under realistic conditions where individuals use more than a single resource, and improve the prediction of responses to current and future ecological changes. Broader Impacts: The research will make broad contributions to society in three ways. (1) The development of K-12 lesson plans to enhance science education, contributing to the broader goal of enhancing early STEM education in the United States. This aspect of the project brings together local grade school teachers, undergraduate students in elementary education from the University of South Carolina (USC), and experts from the USC Center for Science Education to develop a series of lesson plans based on the proposed scientific investigations. (2) Improve commonly used chemical tool (stable isotopes) used in assessing food web links in ecological systems. (3) Improve understanding of species of management concern. Several of the study species are of management concern because they are either problematic invaders in many areas globally, are currently increasing in abundance as a result of reduced consumer pressure because of overfishing, or are dominant yet understudied consumers in their respective habitats. This study will provide important information on the impacts of these species, as well as on their reproductive potential.