Collaborative Research: Testing eco-evolutionary trophic cascades in aquatic ecosystems

合作研究：测试水生生态系统中的生态进化营养级联

• 批准号: 1457333
• 负责人: Eric Palkovacs
• 金额: $ 27.62万
• 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: 2015
• 资助国家: 美国
• 起止时间: 2015-05-15 至 2019-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1457333&HistoricalAwards=false
• 关键词: Collaborative; Research; Testing; eco; evolutionary

Changes to predator communities are occurring on a global scale. Because top predators can exert strong pressures on other species in a community, it is important to understand the consequences of their losses or gains. Will re-introduction of wolves alter current elk or moose populations? Will the loss of marine predators cause fish communities to collapse? These expectations often generate controversy. This project tests how evolutionary responses of prey to their predators might alter commonly-expected results of cascading effects within food chains. Predation, trophic cascades, and evolution are features of all natural ecosystems. Understanding how these processes interact is fundamental to interpreting past ecosystem changes and to predicting future changes. The results from this study will directly inform many of the controversies attending management of large predators. High school teachers and undergraduate students with teaching aspirations will be introduced to the ecological relevance of evolution through hands-on involvement in the research. This teacher training program will target teachers and students from traditionally underrepresented groups who work, or plan to work, in high needs schools with diverse and underprivileged students. The study of eco-evolutionary dynamics considers how ongoing evolution interacts with ecological interactions to shape population, community and ecosystem processes. Intriguing case studies suggest the effects of contemporary evolution on ecology can be large, but this area of research lacks theory that would extend its general importance. This research serves as a potential general application of the broader synthetic theory of eco-evolutionary dynamics through study of trophic cascades. It will provide an initial test of the requisite conditions of eco-evolutionary trophic cascades and quantitatively compare the magnitude and pattern of their effects to those of classical density- and behaviorally-mediated trophic cascades to understand their importance. Field surveys, manipulative experiments, and common garden experiments will be integrated to test the following predictions: 1) prey feeding traits in wild populations differ predictably in response to predator presence or absence, 2) feeding trait differences are heritable, 3) heritable differences in prey traits affect the density and species composition of prey resources, and 4) effects on prey resources cascade down food chains to influence primary producers. These conditions will be tested using recently introduced populations of Western mosquitofish inhabiting ponds with or without predatory largemouth bass. Mosquitofish are a classic system for studying both trophic cascades and contemporary evolution, and preliminary evidence supports evolutionary trade-offs between predator avoidance and resource competition. Numerous wild populations, small body size, short life span, and easy husbandry make this species well suited for the combined field and laboratory assays required for this research.

食肉动物群落的变化正在全球范围内发生。因为顶级捕食者可以对群落中的其他物种施加强大的压力，所以了解它们的损失或收益的后果是很重要的。狼群的重新引入会改变目前麋鹿和驼鹿的数量吗？海洋捕食者的减少会导致鱼类群落的崩溃吗？这些期望经常引发争议。该项目测试了猎物对捕食者的进化反应如何改变食物链中级联效应的普遍预期结果。捕食、营养级联和进化是所有自然生态系统的特征。了解这些过程如何相互作用是解释过去生态系统变化和预测未来变化的基础。这项研究的结果将直接告知许多关于大型食肉动物管理的争议。高中教师和有教学抱负的本科生将通过亲身参与研究，介绍进化的生态相关性。这一教师培训项目将针对来自传统上未被充分代表的群体的教师和学生，他们在拥有多样化和贫困学生的高需求学校工作或计划工作。生态进化动力学的研究考虑了正在进行的进化如何与生态相互作用相互作用，以塑造人口，群落和生态系统过程。有趣的案例研究表明，当代进化对生态学的影响可能很大，但这一领域的研究缺乏能够扩展其普遍重要性的理论。本研究通过对营养级联的研究，为更广泛的生态进化动力学综合理论提供了潜在的一般应用。它将对生态进化营养级联的必要条件进行初步测试，并将其影响的大小和模式与传统的密度和行为介导的营养级联进行定量比较，以了解其重要性。野外调查、操纵实验和普通花园实验将综合验证以下预测：1)野生种群的猎物摄食性状在捕食者存在或不存在的情况下具有可预测的差异；2)摄食性状的差异是可遗传的；3)猎物性状的遗传差异影响猎物资源的密度和种类组成；4)对猎物资源的影响沿着食物链向下延伸，影响初级生产者。这些条件将用最近引进的西部食蚊鱼种群来测试，这些种群居住在有或没有掠食性大口黑鲈的池塘里。食蚊鱼是研究营养级联和当代进化的经典系统，初步证据支持在捕食者躲避和资源竞争之间的进化权衡。野生种群众多，体型小，寿命短，易于饲养，使该物种非常适合本研究所需的野外和实验室联合分析。