Community Phylogeny and Global Phylogeography of the Neuston

诺斯顿的群落系统发育和全球系统发育地理学

• 批准号: 0850625
• 负责人: Diarmaid O'Foighil
• 金额: $ 38.18万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0850625&HistoricalAwards=false
• 关键词: Community; Phylogeny; Global; Phylogeography; Neuston

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."This project aims to construct the first marine community phylogeny. It is inspired by the integrative perspective that lies at the core of the modern concept of biodiversity. Empirical realization of this integration requires that study systems be simple enough to be tractable, yet (ideally) contain compelling ecological and evolutionary phenomena. The target marine community, the neuston, embodies these characteristics to an exceptional degree. It consists of a relatively small number of interacting species that drift at the water/atmosphere interface of the planet's subtropical gyres (40% of oceanic surface area) and play an important role in open-ocean epipelagic food webs. The ecological base of the neuston community is an endosymbiosis involving chondrophore cnidarian hosts (Porpitidae) and their dinoflagellate photosymbionts. Chondrophores are preyed upon by a variety of predators, chief among them two lineages of highly specialized gastropods (Janthinidae and Glaucinae). This prominent open ocean community has been poorly studied, apart from its resident insect genus Halobates. The investigator aims to complete a combined phylogeny/phylogeography of neuston taxa across three trophic levels (photosymbionts, chondrophore hosts, predatory gastropods) and all 5 subtropical gyre systems. The two main goals of the community phylogeny section are to determine the evolutionary origins of the photosymbiosis, and to establish the benthic sister lineages of both gastropod lineages in order to identify the synapomorphic changes associated with ancestral ecological transitions from benthos to neuston. The primary aims of the phylogeographic section are to establish the spatial scale of speciation for the target neustonic taxa, and to test three hypotheses of within-species genetic structuring: global panmixis; ocean basin panmixis; within gyre panmixis. The investigator has developed a multi-faceted sampling strategy that involves ichthyoplankton research colleagues in multiple gyres systems, the bi-coastal, ocean-going ships and students of the Woods Hole Semester at Sea program, national and international museum collections, and an informal network of colleagues worldwide that will sample spontaneous neuston stranding event. He has also established collaborative relationships with colleagues expert in cnidarian, nudibranch, caenogastropod and epitoniid diversity, who will work closely with him on their respective groups within the neuston and, for gastropods, also within benthic sister lineages. To-date, preliminary samples from 3 of the 5 gyres have yielded results that not only demonstrate the feasibility of the primary project goals, but also provide exciting initial insights into the generality of the photosymbiotic association, the putative benthic sister lineages of neustonic gastropods, the likely presence of cryptic species complexes, and the divergent patterns of among-gyre and among-basin genetic structuring exhibited by sister taxa.This project has an unusually extensive student outreach component in the form of the 100 Sea Education Association (SEA) undergraduates and high school students that will participate in multiple upcoming SSV Seamans & SSV Cramer cruises and who will collect neuston taxa. The investigator will provide detailed electronic feedback to the SEA courses, in the field, so that students will be able to connect the organisms they collect with the biogeographic and evolutionary hypotheses being testing, and to determine for themselves which hypotheses the available data reject, or corroborate. One graduate and three undergraduate UM students will receive in-depth training during this project. The graduate student, Celia Churchill, has participated in offshore neuston sampling, generated much of the preliminary data, and recently presented at her first scientific meeting. She will work/train with the P.I., and also with 4 expert collaborators, directly in their laboratories for 2 of them. One UM undergraduate student has already worked directly on this project and the investigator will recruit at least two more. Substantial international outreach and collaborative activities are planned across research specialties, especially involving ichthyoplankton colleagues working in different gyre systems, as well as international museum colleagues. This study promises to significantly enhance background knowledge of the vast subtropical gyre surface ecosystem, now heavily impacted, even in mid-ocean, by the incremental accumulation of non-biodegradable, plastic flotsam. This is a major new marine conservation issue that is just now entering public discourse, e.g., see recent descriptions of the North Pacific's Giant Garbage Patch in the popular press.

“这项奖励是根据2009年美国复苏和再投资法案（公法111-5）资助的。”本项目旨在构建第一个海洋群落系统发育。它的灵感来自于现代生物多样性概念核心的综合视角。这种整合的经验实现要求研究系统足够简单，易于处理，但（理想情况下）包含引人注目的生态和进化现象。目标海洋群落，即纽斯顿，在很大程度上体现了这些特征。它由相对较少的相互作用物种组成，它们在地球副热带环流（占海洋表面积的40%）的水/大气界面上漂移，并在开放海洋的上层海洋食物网中发挥重要作用。线虫群落的生态基础是一种涉及软骨细胞刺胞宿主（porportidae）和它们的鞭毛光共生体的内共生关系。软骨软骨动物是各种捕食者的猎物，其中主要是两种高度特化的腹足动物（Janthinidae和Glaucinae）。这个突出的开放海洋群落的研究很少，除了它的常驻昆虫属盐藻。研究者的目标是在三个营养水平（光共生体、软骨寄主、掠食性腹足类）和所有5个亚热带环流系统中完成新生物类群的系统发育/系统地理学。群落系统发育部分的两个主要目标是确定光共生的进化起源，并建立两个腹足动物谱系的底栖姐妹谱系，以确定与从底栖动物到水生动物的祖先生态转变相关的突触形态变化。系统地理部分的主要目的是建立目标神经系统分类群的物种形成的空间尺度，并检验种内遗传结构的三种假设：全球泛群；洋盆泛海；在环流panmixis内。研究者已经制定了一个多方面的采样策略，包括在多个环流系统中研究浮游鱼的同事，双海岸，远洋船只和伍兹霍尔海上学期项目的学生，国家和国际博物馆的收藏，以及一个非正式的全球同事网络，将对自发的neuston搁浅事件进行采样。他还与同事们建立了合作关系，他们是刺胞动物、裸鳃动物、caenogastropod和表形动物多样性方面的专家，他们将与他密切合作，研究他们各自在neuston中的群体，对于腹足类动物，也包括底栖动物的姐妹谱系。迄今为止，来自5个环流中的3个的初步样本所取得的结果不仅证明了主要项目目标的可行性，而且还提供了令人兴奋的初步见解，以了解光共生关联的普遍性，神经性腹足类的假定底栖姐妹谱系，可能存在的隐物种复合体，以及姐妹分类群在环流和盆地间表现出的遗传结构的不同模式。该项目以100名海洋教育协会（Sea）本科生和高中生的形式进行了异常广泛的学生外展，他们将参加即将到来的多次SSV Seamans和SSV Cramer巡航，并将收集新物种。研究者将为现场的SEA课程提供详细的电子反馈，以便学生能够将他们收集的生物体与正在测试的生物地理和进化假设联系起来，并自行确定可用数据拒绝或证实哪些假设。一名研究生和三名本科生将在此项目中接受深入培训。研究生西莉亚·丘吉尔（Celia Churchill）参与了海上新闻取样，产生了许多初步数据，最近在她的第一次科学会议上发表了报告。她将与私家侦探一起工作/培训，并与4名专家合作者一起，直接在他们的实验室中进行其中2项工作。一名澳大本科生已经直接参与了这个项目，研究者将至少再招募两名。大量的国际推广和合作活动计划跨研究专业，特别是涉及在不同的环流系统中工作的浮游鱼同事，以及国际博物馆的同事。这项研究有望显著增强对巨大的亚热带环流表面生态系统的背景知识，现在，即使在海洋中部，也受到不可生物降解的塑料漂浮物的不断积累的严重影响。这是一个重要的新的海洋保护问题，现在刚刚进入公众话语，例如，看看最近在大众媒体上对北太平洋巨型垃圾带的描述。