COLLABORATIVE RESEARCH: LTREB: Long-term ecological and evolutionary dynamics of secondary contact

合作研究：LTREB：二次接触的长期生态和进化动力学

• 批准号: 2102763
• 负责人: Eric Palkovacs
• 金额: $ 17.96万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-15 至 2026-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2102763&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; LTREB; Long; term

Populations of animals and plants are regularly isolated by natural processes and human activities. In isolation, populations adapt to local environments, and traits and genes may diverge. This adaptive divergence can create ecologically important variation that changes the role of species within ecosystems. Natural processes and human activities can also allow or force populations that have diverged in isolation to come back into contact - a process called secondary contact. The outcome of secondary contact is important for understanding how populations evolve and ecosystems function. This LTREB takes advantage of a whole-lake restoration project to study the decade-scale ecological and evolutionary dynamics of secondary contact between recently diverged lineages of alewife. Alewife are a well-studied and ecologically important fish found in lakes and in the coastal ocean of eastern North America. There are two divergent alewife life-history forms: the ancestral anadromous form that moves between lakes and the coastal ocean and a landlocked form that is resident in lakes. Many landlocked populations were formed by the construction of dams by colonial Americans. The recent removal of dams and construction of fishways create opportunities for secondary contact between landlocked and anadromous alewife populations. Findings will address questions fundamental to the generation and maintenance of biodiversity, the ecological impact of variation within species, and the impacts of human accelerated environmental changes including population fragmentation, restoration of habitat connectivity, and climate change. This project will inform the conservation and management of anadromous alewife, a critical resource in coastal freshwater and marine habitats, a species of conservation concern, and the focus of intensive restoration and conservation efforts. The genomic tools developed by this project will help resource managers address important questions, such as the impact of bycatch on anadromous alewife populations. The project will train graduate and undergraduate students, including students from underrepresented backgrounds, in a unique combination of advanced genomics techniques and whole-lake sampling. This project asks how climate change, anadromous alewife population recovery, and periodic major hybridization events (2-3 per decade), interact to determine the magnitude of hybridization and direction of gene flow, phenotypic differentiation among alewife forms, and whole-lake impacts. It focuses on the restoration of Rogers Lake, Connecticut and regional reference lakes. This project utilizes highly informative microhaplotype genetic markers to measure hybridization and gene flow; measures trophic morphology, individual growth rates, diets, and habitat use to assess phenotypic and ecological differentiation among forms; and samples inorganic nutrients, phytoplankton, and zooplankton to evaluate whole-lake impacts. This research provides a rare opportunity to track the ecological and evolutionary dynamics from the initiation of secondary contact, and the long-term research plan facilitates the detection of rare events and interactions between ecological and evolutionary process at the whole ecosystem scale.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.

动物和植物种群经常因自然过程和人类活动而被隔离。在孤立的情况下，种群会适应当地环境，性状和基因可能会出现差异。这种适应性分歧可以产生生态上重要的变异，从而改变物种在生态系统中的作用。自然过程和人类活动也可以允许或迫使孤立分散的人群重新接触——这一过程称为二次接触。二次接触的结果对于了解种群如何进化和生态系统功能非常重要。该 LTREB 利用全湖恢复项目来研究最近分化的白鹳鳅谱系之间二次接触的十年尺度的生态和进化动态。 Alewife 是一种经过充分研究且具有重要生态意义的鱼类，发现于北美东部的湖泊和沿海海洋中。有两种不同的生活史形式：在湖泊和沿海海洋之间移动的祖先溯河产卵形式和居住在湖泊中的内陆形式。许多内陆人口是由美洲殖民地修建水坝形成的。最近水坝的拆除和鱼道的建设为内陆和溯河产卵的白鳀种群之间的二次接触创造了机会。研究结果将解决生物多样性产生和维持的基本问题、物种内变异对生态的影响，以及人类加速环境变化的影响，包括人口破碎、栖息地连通性的恢复和气候变化。该项目将为溯河产卵鳀鱼的保护和管理提供信息，鳅鳅是沿海淡水和海洋栖息地的重要资源，是一种受保护的物种，也是强化恢复和保护工作的重点。该项目开发的基因组工具将帮助资源管理者解决重要问题，例如兼捕对溯河产卵鳀鱼种群的影响。该项目将以先进的基因组学技术和全湖采样的独特组合来培训研究生和本科生，包括来自弱势背景的学生。 该项目探讨气候变化、溯河产卵鳅鱼种群恢复和周期性重大杂交事件（每十年 2-3 次）如何相互作用，以确定杂交的程度和基因流方向、鲅鱼形态之间的表型分化以及整个湖的影响。它的重点是恢复康涅狄格州罗杰斯湖和区域参考湖泊。该项目利用信息丰富的微单倍型遗传标记来测量杂交和基因流；测量营养形态、个体生长率、饮食和栖息地利用，以评估不同形式的表型和生态分化；并对无机营养物、浮游植物和浮游动物进行采样，以评估整个湖泊的影响。这项研究提供了一个难得的机会来跟踪从二次接触开始的生态和进化动态，长期研究计划有助于在整个生态系统尺度上检测罕见事件以及生态和进化过程之间的相互作用。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

The Evolutionary Consequences of Dams and Other Barriers for Riverine Fishes

水坝和其他屏障对河流鱼类的进化后果

• DOI: 10.1093/biosci/biac004
• 发表时间: 2022
• 期刊: BioScience
• 影响因子: 10.1
• 作者: Zarri, Liam J.;Palkovacs, Eric P.;Post, David M.;Therkildsen, Nina O.;Flecker, Alexander S.
• 通讯作者: Flecker, Alexander S.