LTREB Renewal: Evolutionary Dynamics in a Rapidly Changing Environment

这项研究的目的是了解一个物种在经历快速变化的环境时，自然选择是如何随时间变化的。这项研究建立在广泛的长期（自1962年以来）数据集上，这些数据集是科罗拉多州落基山生物实验室单独标记的黄腹土拨鼠。该项目将测量土拨鼠个体的关键生理和行为特征的变化，并确定它们对这种模式生物的繁殖和生存的影响。这项工作很重要，因为它将提供新的数据和见解，以更好地理解对环境变化的进化反应的局限性。这项工作将继续对居住在不同海拔地区的土拨鼠种群的适应性变化（即繁殖成功率和存活率）进行长期记录，并将其与这些哺乳动物的体重、攻击性和统治行为等特征联系起来。这些数据的延续为研究气候变化对冬眠哺乳动物的影响提供了一个宝贵的窗口，也是一个无价的数据集，可用于探索种群和进化动态。该项目的更广泛影响将包括：招募和培训来自代表性不足群体的研究生和本科生；通过科学和通俗的文章和讲座向科学受众和公众广泛传播研究成果，并与科学记者合作；维护博客和网站，提供旱獭生物学和生态学的公共信息。本项目将在落基山生物实验室评估低海拔和高海拔地区土拨鼠种群的环境变化、选择压力和性状差异。这项工作将扩展早期对体重特征的分析，如出现时的体重、体重增加率和冬眠前的体重。对选择和性状分布变化的分析将基于过去40年和未来2-3年。PI将使用12-15年的数据重点分析行为和内分泌性状，并结合通径分析来检验因果关系，并使用多变量动物模型将性状方差分解为环境和遗传成分。通过量化性状选择如何随时间变化，繁殖成功和生存的变化如何影响性状，以及这些性状的变化如何影响繁殖和生存，本研究将整合近因机制和最终机制，并使用新的方法来研究因果推理。

The purpose of this study is to understand how natural selection changes over time for a species experiencing a rapidly changing environment. This research builds on an extensive long-term (since 1962) data set of individually marked yellow-bellied marmots at Rocky Mountain Biological Laboratory in Colorado. The project will measure changes in key physiological and behavioral traits of individual marmots, and determine their influence on reproduction and survival in this model organism. This work is important because it will provide new data and insights to better understand the limits of evolutionary responses to environmental change. The work will continue a long term record of changes in fitness (i.e., reproductive success and survival) for populations of the marmot inhabiting different elevations, and linking this to traits like body mass, aggression, and dominance behavior in these mammals. Continuation of this data provides a valuable window on the effects of climate change on a hibernating mammal, and a priceless data set that can be used to explore both population and evolutionary dynamics. Broader impacts of this project will include: recruitment and training of graduate and undergraduate students from under-represented groups; wide dissemination of research results to scientific audiences and the general public via scientific and popular articles and talks, and working with science journalists; and maintenance of a blog and website to provide public information on marmot biology and ecology. This project will evaluate changes in the environment, in selection pressure, and in trait variance of marmot populations at both low and high elevation sites at Rocky Mountain Biological Laboratory. The work will expand earlier analyses on body mass traits such as mass at emergence, rate of mass gain, and mass before hibernation. Analyses of changes in selection and in trait distributions will be based on the past 40 years and the next 2-3 years. The PI will focus analyses on behavioral and endocrine traits using 12-15 years of data, and use a combination of path analysis to test for causality and the multivariate animal model to decompose trait variance into its environmental and genetic components. By quantifying how selection on traits changes over time, how changes in reproductive success and survival affects traits, and how changes in these traits affect reproduction and survival, this research will integrate proximate and ultimate mechanisms and use novel approaches to study causal inference.