Dissertation Research: Molecular Systematics and Historical Biogeography of the Holarctic Fish Genus Cottus (Scorpaeniformes: Cottidae)

论文研究：全北极鱼属 Cottus（鲉形目：Cottidae）的分子系统学和历史生物地理学

• 批准号: 0206676
• 负责人: Robert Wood
• 金额: $ 0.76万
• 依托单位: Saint Louis University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0206676&HistoricalAwards=false
• 关键词: Dissertation; Research; Molecular; Systematics; Historical

A grant has been awarded to Dr. Robert Wood and Mr. Andrew Kinziger of Saint Louis University to study the genus Cottus; a group of small benthic fishes with flattened heads and enlarged pectoral fins. Cottus is comprised of approximately 42 total species inhabiting both freshwater and marine environments in North America, Japan, and Eurasia. The genus is one of the most poorly studied components of the North American fish fauna. Major problems preventing a more complete understanding of Cottus evolutionary biology include: (1) lack of a hypothesis of relationships among members of the genus; (2) uncertainty concerning the exact number of species in the genus; and (3) questions as to whether the members of the genus form a cohesive or logical group. To address these problems the investigators propose to generate a hypothesis of relationships among Cottus species using 2619 bases of DNA sequence data.The hypothesis of relationships will provide a foundation to address the three major problems discussed above and allow for the evaluation of two interesting evolutionary questions. First, the hypothesis can be used to reconstruct the evolutionary history of transitions between marine and freshwater environments, a fascinating evolutionary phenomenon because it involves modification of several physiological mechanisms that allow organisms to cope with extremely different environments. Second, the phylogenetic hypothesis can be used to assess hypotheses responsible for the speciation and the distribution of members of the genus: (1) the break up of the supercontinent Pangea; (2) connections created by land bridges; and (3) dispersal between freshwater and marine environments. Further, the investigators proposed work will provide the framework for future research on Cottus evolutionary biology and furnish important information concerning those Cottus species of conservation concern.

圣路易斯大学的Robert Wood博士和Andrew Kinziger先生获得了一笔研究Cottus属的拨款；一种小的底栖鱼类，头部扁平，胸鳍增大。Cottus由大约42种组成，生活在北美、日本和欧亚大陆的淡水和海洋环境中。该属是北美鱼类动物群中研究最少的组成部分之一。阻碍我们更全面地了解棉蝇进化生物学的主要问题包括：(1)缺乏对棉蝇属成员之间关系的假设；（二）属中物种的确切数目不确定的；(3)关于属的成员是否构成一个连贯的或逻辑的群体的问题。为了解决这些问题，研究者提出利用2619个碱基的DNA序列数据来产生一个棉科植物之间关系的假设。关系假说将为解决上面讨论的三个主要问题提供基础，并允许对两个有趣的进化问题进行评估。首先，这一假说可以用来重建海洋和淡水环境之间过渡的进化史，这是一个令人着迷的进化现象，因为它涉及到一些生理机制的修改，使生物体能够应对极端不同的环境。其次，系统发育假说可以用来评估对物种形成和属成员分布负责的假说：(1)泛大陆的分裂；（二）陆桥连接；(3)在淡水和海洋环境之间扩散。本研究为今后棉科植物的进化生物学研究提供了框架，并为棉科植物的保护提供了重要信息。