CAREER: ECO-EVOLUTIONARY DYNAMICS: WHAT ARE THE CAUSAL LINKS BETWEEN POPULATION DENSITY, NATURAL SELECTION AND PHENOTYPIC CHANGE?

促进早期职业教师学者的发展加强了国家的研究能力，同时有助于培养有能力做出复杂决策的受过良好教育的劳动力。这个CAREER项目整合了跨学科研究和创造性的教育机会，以获得关于进化变化和种群生态学之间因果关系的新见解。自然选择、表型变化和种群规模通常是相关的，但我们对这些关系背后的原因知之甚少。该研究利用在入侵的西部蓝鸟中观察到的快速进化变化来调查这些因果关系，并让高中生、本科生和研究生进行批判性思考，以解决问题和回答问题。西部蓝鸟依赖于连续的栖息地，必须不断地在新的地区定居才能生存。在之前的工作中，研究者发现攻击性、人口密度和自然选择的快速变化伴随着重新定居周期。新殖民群体具有低密度、高侵略性和正向选择侵略性的特点；老年种群密度高，攻击性低，攻击性负向选择强。这些循环为研究种群密度、自然选择和表型变化之间的因果关系提供了一个独特的机会。研究者将结合几种方法来确定这些联系：实验操纵人口密度；观察密度变化与攻击性的关系；实验操作食物供应和生存，以确定侵略和人口规模的变化；以及与攻击性相关的定量遗传参数的估计。研究结果将被整合，以解决这些种群中进化（侵略选择）和生态（种群密度）变化之间的因果关系。这个系统特别适合通过提供筑巢箱来操纵生态相互作用，而且西部蓝鸟重新定居新地区的需要需要快速的进化变化。在一个殖民周期的不同阶段研究种群的能力，为研究生态进化反馈回路各组成部分之间的联系提供了不同的背景。这项研究的一个特别新颖的更广泛的影响是让认知迟缓的学生参与进来，帮助他们获得重要的生活技能。与公民科学家、萨利希联盟和库特奈部落、保护团体、野生动物官员和土地所有者的接触和合作将大大拓宽教育机会和研究成果的传播。

Fostering the development of early-career teacher-scholars strengthens the nation's research capacity while contributing to an educated workforce capable of making complex decisions. This CAREER project integrates interdisciplinary research and creative educational opportunities to gain novel insights into the causal links between evolutionary change and population ecology. Natural selection, phenotypic change, and population size are often related, but we know little about the causes that underlie these relationships. The research takes advantage of rapid evolutionary change observed in the invasive western bluebird to investigate these causal relationships, and engages high school, undergraduate, and graduate students to think critically in order to solve problems and answer questions. Western bluebirds depend on successional habitat and must continually colonize new areas to survive. In previous work, the investigator discovered rapid shifts in aggression, population density, and natural selection that accompanied recolonization cycles. Newly colonized populations have low density, high aggression, and positive selection on aggression; older populations have high density, low aggression, and strong negative selection on aggression. These recurring cycles provide a unique opportunity to investigate the causal links between population density, natural selection and phenotypic change. The investigator will combine several approaches to determine these links: experimental manipulation of population density; observations of how changing density correlates with aggression; experimental manipulation of food availability and survival to identify changes in aggression and population size; and estimation of quantitative genetic parameters related to aggressiveness. Results will be integrated to resolve the causal links between evolutionary (selection for aggression) and ecological (population density) changes in these populations. This system is exceptionally amenable to manipulation of ecological interactions through the provision of nesting boxes, and the need for western bluebirds to recolonize new areas requires rapid evolutionary change. The ability to study populations at different stages of a colonization cycle provides diverse contexts to examine the links between components of an eco-evolutionary feedback loop. A particularly novel broader impact of this research is the engagement of cognitively delayed students to help them gain important life skills. Outreach to and collaboration with citizen scientists, the Confederated Salish and Kootenai Tribes, conservation groups, wildlife officials, and landowners will significantly broaden educational opportunities and the dissemination of research results.