CAREER: Ecological and Evolutionary Drivers in an Invasive Host-Parasite System

入侵物种造成了大规模的经济和环境损失。尽管付出了这些代价，但目前仍不清楚是什么生态和进化过程推动了入侵，特别是对寄主物种及其寄生虫的入侵。这项研究将着眼于局部适应和传播能力在推动入侵宿主和寄生虫种群之间的遗传差异方面的重要性。当入侵物种在一个新的地点定居时，它会迅速开始适应当地的环境。随着这种适应的进行，入侵种群之间的遗传差异可能会出现，并改变宿主和寄生虫相互影响的方式。研究还将考虑传播能力的作用，特别是宿主在合适的栖息地之间移动的能力和寄生虫在宿主之间移动的能力。它将调查扩散能力以及栖息地之间的差异如何影响入侵宿主和寄生虫的局部适应模式。该项目将大大提高我们对寄主和寄生虫成功入侵新栖息地的方式的了解，从而有助于改进管理工作。此外，该项目将对本科生和研究生进行生态学和进化论研究方法、教学方法、科学交流和指导方面的培训。大学和中学生之间的服务学习伙伴关系将通过参与基于探究的科学研究来提高生物专业学生的代表性和归属感。有兴趣参与类似框架的教育工作者网络将广泛分享计划的目标和成功。复杂的宿主-寄生虫系统，即一个寄生虫使用多个宿主物种的系统，为更好地了解入侵动态提供了独特的挑战和机会。这里要探索的系统是入侵的水龙头蜗牛及其吸虫寄生虫。水龙头蜗牛(Bithynia Tenaculata)于20世纪初从欧洲传入北美。几种吸虫以水龙头螺为宿主，在水禽中完成其生命周期，导致小干酪(Aythya Affinis)等物种的高死亡率。研究目标包括：1)使用基因组测序重建蜗牛宿主和吸虫寄生虫的入侵历史，并比较入侵情景的进化模型；2)使用实验性的大规模交叉感染设计，确定活跃入侵景观中蜗牛和吸虫种群之间的局部适应模式；3)使用现场和实验室相结合的方法，确定扩散和栖息地异质性对种群结构和局部适应模式的相对贡献。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Invasive species are responsible for large-scale economic and environmental losses. Despite these costs, it is still unclear what ecological and evolutionary processes drive invasions, especially for host species and their parasites. This research will look at the importance of local adaptation and dispersal ability in driving genetic differences among populations of invasive hosts and parasites. When an invasive species establishes in a new location, it rapidly begins to adapt to its local surroundings. As this adaptation proceeds, genetic differences between invasive populations can emerge and change the way in which hosts and parasites affect one another. The research will also consider the role of dispersal ability, specifically the ability of hosts to move between suitable habitats and of parasites to move between hosts. It will investigate how dispersal ability together with variation among habitats affect patterns of local adaptation for invasive hosts and parasites. The project will significantly advance our understanding of the ways in which hosts and parasites successfully invade new habitats, thereby helping to improve management efforts. In addition, the project will train undergraduate and graduate students in ecological and evolutionary research methods, teaching methods, science communication, and mentorship. A service-learning partnership between university and middle school students will improve representation and sense of belonging for students pursuing biology through engagement in inquiry-based scientific research. Program goals and successes will be broadly shared among a network of educators interested in participating in similar frameworks.Complex host-parasite systems, those in which a parasite uses multiple species of hosts, present a unique challenge and opportunity to better understand invasion dynamics. The system to be explored here is the invasive faucet snail and its trematode parasites. The faucet snail (Bithynia tentaculata) was introduced from Europe to North America in the early 1900s. Several species of trematodes are hosted by faucet snails and complete their life cycle in waterfowl, causing high rates of mortality in species such as Lesser Scaup (Aythya affinis). Research goals include: 1) using genomic sequencing to reconstruct invasion histories of snail hosts and trematode parasites and comparing evolutionary models of invasion scenarios, 2) determining patterns of local adaptation among snail and trematode populations across an active invasion landscape using an experimental, large-scale cross infection design, and 3) determining the relative contributions of dispersal and habitat heterogeneity to patterns of population structure and local adaptation using a combination of field and lab-based approaches.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.