ECOLOGICAL AND EVOLUTIONARY RESILIENCE OF AQUATIC COMMUNITIES TO THE CLIMATE-MEDIATED EXPANSION OF AN APEX PREDATOR

生态学的一个持续挑战是了解生态系统如何对环境干扰做出反应。气候变化就是这样一种干扰，预计将导致全球生物多样性的重新组织，包括物种地理分布的变化和灭绝速度的增加。当地物种种群的变化可能会影响生态系统的功能及其为人类提供的服务。然而，如果物种能够更好地适应新的气候，或者如果当地人口能够适应变化，自然生态系统可能会被证明比我们认为的更具弹性。在这个项目中，研究人员将操纵整个池塘，以了解这些生态系统对气候诱导的顶级水生捕食者扩张的适应能力。随着冬天变暖，大理石花纹蜥蜴正迅速在新英格兰的新合适的临时池塘中定居。大理石蜥蜴是这些池塘的顶级捕食者，可以极大地减少生物多样性，并将池塘生态系统转变为以藻类产量高为特征的状态。除了对基础科学和保护做出贡献外，该项目还将对社会产生更广泛的影响。调查人员将为K-12教师创建一个科学实习机会，并为来自代表性不足群体的学生创建一个本科生实习机会。他们还将开发一个连接在一起的远程摄像机系统来记录和播放一年一度的两栖动物迁徙，作为公众出游的一种手段。在一个气候变化正在推动顶级捕食者迅速扩张的地区，调查人员将量化移民和适应进化如何促进生态和进化救援。这项工作将侧重于物种迁徙产生的生态复原力，这些物种可以恢复多样性并取代失去的功能角色，以及先前显示的中介消费者的适应性进化，以调解顶端捕食者对群落结构的影响。该项目通过以下方式推进基本和应用问题：1)通过平行、重复、全生态系统实验对复原力理论进行首批测试之一；2)对复原力的生态机制和进化机制进行比较；3)挑战现有范式，即对生物反应的预测可能会忽略景观连通性和适应性变化；4)启动一项关于野生脊椎动物进化的重要长期研究；以及5)对顶端捕食者如何在变暖的世界中扩张时改变淡水系统进行概括性的理解。该项目采取了多层次的方法，以深入了解对捕食者跨空间和跨时间引入的两种基本反应，以帮助建立对生态进化对食物网变化的抵抗的更广泛、更机械的理解。

An ongoing challenge in ecology is to understand how ecosystems respond to environmental disturbances. Climate change is one such disturbance that is expected to result in a re-organization of global biodiversity, including shifts in species geographic distribution and increases in rates of extinctions. Alterations in local species populations may impact the functioning of ecosystems and the services they provide for humans. However, natural ecosystems might prove more resilient that we think if species better adapted to new climates can immigrate or if local populations can adapt to the changes. In this project, researchers will manipulate entire ponds to understand the degree to which these ecosystems are resilient to the climate-induced expansion of a top aquatic predator. As winters warm, the marbled salamander is rapidly colonizing newly suitable temporary ponds in New England. Marbled salamanders are top predators in these ponds and can strongly reduce biodiversity and shift pond ecosystems to a state characterized by high algal production. The project will have broader impacts on society beyond contributing to fundamental science and conservation. The investigators will create a scientific internship for K-12 teachers and an undergraduate internship focusing on students from underrepresented groups. They will also develop a system of linked remote video cameras to record and broadcast the annual amphibian migration, as a means of public outreach.In a region where climate change is promoting the rapid expansion of a top predator, the investigators will quantify how immigration and adaptive evolution facilitate ecological and evolutionary rescue. The work will focus on ecological resilience originating from the immigration of species that can restore diversity and replace lost functional roles and the adaptive evolution of an intermediate consumer previously shown to mediate the impacts of the apex predator on community structure. The project advances fundamental and applied questions by 1) performing one of the first tests of resilience theory in parallel, repeated, whole-ecosystem experiments; 2) allowing a comparison of ecological versus evolutionary mechanisms of resilience; 3) challenging the existing paradigm that predictions about biotic responses can ignore landscape connectivity and adaptive variation; 4) initiating an important long-term study on evolution in wild vertebrates; and 5) developing a generalizable understanding of how apex predators alter freshwater systems as they expand in a warming world. The project takes a multi-tiered approach in order to develop insights about two fundamental responses to predator introductions across space and time to contribute to building a broader, more mechanistic understanding of eco-evolutionary resistance to food web changes.