CAREER: Empirically evaluating the genomic consequences of assisted migration in heterogeneous environments

应对人为气候变化既是一个社会学问题，也是一个科学问题。目前的研究表明，许多物种现在落后于不断变化的气候条件，相对于过去的条件来说表现不佳。确定哪些物种受到影响，物种减少的速度有多快，以及评估应对物种减少的潜在解决方案是关键目标。一个潜在的解决方案是协助移民，即有意将来自地理上遥远的人口中更能适应不断变化的条件的个人引入重点人口。辅助迁移是有争议的，因为在将新的变异引入种群时通常会有未知的后果，而且它在很大程度上没有通过受控实验进行测试。该奖项实验性地解决了在一种分布广泛的植物中辅助迁移的后果，这种植物在其分布的一小部分中受到威胁。将把已经适应当代条件的种群的种子和幼苗引入重点种群的一个子集。这些实验种群和附近对照种群之间的性状、基因组和种群成功率的比较将提供迄今为止收集的关于辅助迁移的效率和潜在效用的最佳经验数据。该奖项还通过为中学教师提供在课堂上解决这一问题所需的技能，课程计划和信息，来解决公众对美国各地气候变化的理解。该奖项资助创建一个动态的游戏式气候变化外展模块，一个由研究生领导的科学外展团队进入中学教育课堂，以及一个研讨会课程，为有抱负的STEM教师指导教师如何解决有争议的问题。这里授予的辅助迁移实验评估了三个主要问题：引入后在基因组中发生了多少基因渗入，以及它持续了多长时间？基因渗入是否改变了性状分布或使超亲表型出现？在正常年份或极端年份，引种能提高本地种群的适应性吗？该项目通过利用模式生物Mimulus guttatus的基因组资源来解决这些问题。初步数据表明，海拔匹配的加州人口有较高的健身比本地俄勒冈州瀑布人口，和俄勒冈州瀑布人口灭绝的危险，在极端气候年。该项目将加州人口纳入过去三年跟踪的12个人口的子集。引入后渐渗的量和时间将通过使用低覆盖率全基因组测序来调查，以跟踪引入后三年内引入种群特有的遗传变异。一个多年的共同花园实验，在实验期间每年收集的种子将被用来评估表型和健身如何变化后，辅助迁移。虽然这个实验提供了重要的价值，保护社区，它也将提供新的见解，如何在一个自然种群的进化力量相互作用，以消除和保持多态性的快速生态时间尺度。该奖项为主要通过多样性倡议招募的五名本科生研究人员和一名研究生提供培训资金，并通过针对多个年龄组的既定外联活动进行公共传播。该奖项反映了NSF的法定使命，并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，被认为值得支持。

Responding to anthropogenic climate change is both a sociological and a scientific issue. Current studies suggest that many species are now lagging behind changing climatic conditions and are doing poorly relative to past conditions. Determining which species are impacted, how fast species are declining, and evaluating potential solutions to counter declines are key goals. One potential solution is assisted migration, where individuals from a geographically-distant population that are better adapted to the changing conditions are intentionally introduced into a focal population. Assisted migration is controversial because there are often unknown consequences when introducing new variation into a population, and because it has largely been untested via controlled experiments. This award experimentally addresses the consequences of assisted migration in a widespread plant that is threatened in a small portion of its distribution. Seeds and seedlings from populations already adapted to contemporary conditions will be introduced into a subset of focal populations. Comparisons of traits, genomes, and population success between these experimental populations and nearby control populations will provide the best empirical data collected to date on the efficiency and potential utility of assisted migration. This award also addresses the need for greater public understanding of climate change across the U.S. by providing secondary education teachers with the skills, lesson plans, and information necessary to address this issue in the classroom. This award funds the creation of a dynamic game-like climate change outreach module, a graduate student-led science outreach team to go into secondary education classrooms, and a seminar course for aspiring STEM teachers to instruct teachers how to address contentious issues. The assisted migration experiment awarded here evaluates three main questions: how much introgression occurs across the genome following the introduction and how long does it persist? Does introgression shift trait distributions or enable transgressive phenotypes to emerge? Do introductions improve fitness of the native populations in normal or extreme years? This project addresses these questions by leveraging the genomic resources of a model organism, Mimulus guttatus. Preliminary data indicate that elevation-matched California populations have higher fitness than native Oregon Cascades populations, and that Oregon Cascades populations are in danger of extirpation in extreme climatic years. This project introduces California populations into a subset of twelve populations that have been followed for the last three years. The amount and timing of introgression following introduction will be surveyed by using low coverage whole genome sequencing to track genetic variants specific to the introduced populations over three years post-introduction. A multi-year common garden experiment with seeds collected each year during the experiment will be used to evaluate how phenotypes and fitness changes following assisted migration. While this experiment provides important value to the conservation community, it also will provide novel insights into how evolutionary forces interact within a natural population to remove and maintain polymorphism on rapid ecological timescales. This award funds training for five undergraduate researchers and a graduate student recruited primarily through diversity initiatives as well as public dissemination via established outreach events targeting multiple age groups.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.