Collaborative Research: LTREB Renewal: Feedbacks between evolution and demography in severely fragmented prairie populations of the purple coneflower, Echinacea angustifolia

本计画延续紫锥菊自然选择的长期研究。在19世纪初，大草原覆盖了北美的大片地区。从那时起，大约99%的高草草原被摧毁。小的，孤立的草原仍然保持着巨大的生物多样性，但在这些残余的草原上，当地植物的灭绝率高得惊人。这个项目正在推进科学的理解，为什么一些种群灭绝，而另一些种群持续存在。该项目建立在对这些生态和遗传过程以及它们之间影响草原植物物种的反馈的长期调查的基础上。紫色的松果花是草原植物的典型代表，其寿命长，往往几十年，并在其他属性。这项研究是第一个衡量人口适应能力的研究。除了推进科学知识和传播信息的科学家和土地管理员，该项目提供了研究经验和培训，以不同的参与者在一个适合他们的兴趣和职业阶段的水平：高中，大学和研究生，教师和公民科学家在明尼苏达州和芝加哥植物园。该项目使用正式的定量遗传方法和常见的花园实验设计来量化适合度，种群分化和近交衰退的加性遗传方差。研究人员将使用aster统计模型来估计2003年种植的个体的达尔文适应性的遗传变异量，其中许多在2015年首次开花。其他实验将估计由于兄弟姐妹之间的交配而导致的平均适应度的降低。这些研究将与1996年开始的残余人口的人口普查一起，对人口增长率和进化拯救的潜力进行全面评估。这项研究的一个关键优势是，实验是在一个现实的栖息地进行的，包括锥花与其传粉者和食草动物的相互作用。核心数据集包括连续的个体健康记录，包括明尼苏达州10个实验地块和27个自然草原遗迹中超过17，000种植物的年度生存和繁殖。这些数据集在项目结束时将持续长达30年，为长寿物种的进化和生态过程的相互作用提供了一个难得的窗口。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

This project continues a long-term study of natural selection in the purple coneflower, Echinacea angustifolia. At the beginning of the 1800s, prairie covered a great swath of North America. Since then, about 99% of the tallgrass prairie has been destroyed. The small, isolated patches of prairie that remain harbor great biodiversity, yet rates of local plant extinctions are alarmingly high in these remnant prairies. This project is advancing scientific understanding of why some populations go extinct and others persist. This project builds on a long-term investigation of these ecological and genetic processes and feedbacks between them affecting a model prairie plant species. The purple coneflower typifies prairie plants in its long lifespan, often decades, and in other attributes. This study is the first of its kind to measure the capacity of a population to adapt. In addition to advancing scientific knowledge and disseminating information to scientists and land stewards, this project provides research experience and training to diverse participants at a level appropriate for their interests and career stage: high school, college, and graduate students, teachers, and citizen scientists in both Minnesota and at the Chicago Botanic Garden. The project uses formal quantitative genetic approaches and common garden experimental designs to quantify additive genetic variance for fitness, population differentiation, and inbreeding depression. Researchers will use aster statistical models to estimate the amount of genetic variation in Darwinian fitness of individuals planted in 2003, many of which flowered for the first time in 2015. Other experiments will estimate the reduction in mean fitness due to mating between siblings. Together with demographic censuses of remnant populations, started in 1996, these studies will yield comprehensive assessments of population growth rates and the potential for evolutionary rescue. A key strength of the research is that experiments are conducted in a realistic habitat, including interactions of the coneflower with its pollinators and herbivores. The core datasets comprise continuous individual fitness records, including annual survival and reproduction of over 17,000 plants in 10 experimental plots and across 27 natural prairie remnants in Minnesota. These datasets, which will extend up to 30 years by the end of the project, offer a rare window into the interplay of evolutionary and ecological processes of a long-lived species.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.