Phylogeography, speciation and conservation genetics of patagonian fishes

巴塔哥尼亚鱼类的系统发育地理学、物种形成和保护遗传学

• 批准号: 326493-2006
• 负责人: Ruzzante, Daniel
• 金额: $ 2.86万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Special Research Opportunity Program - Project
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=397392
• 关键词: Phylogeography; speciation; conservation; genetics; patagonian

Our objective is to examine the comparative phylogeography of the native fishes of Patagonia. The uplift of the southern Andes beginning in the Miocene (ca. 23 MYA), separated east and west flowing drainage systems and influenced the phylogeographic patterns of the associated biota. The resulting phylogeographic patterns were subsequently affected by the recurring glacial and interglacial periods of the Pleistocene (1.8 MYA - 10,000 BP) and by volcanism. During the Last Glacial Maximum an ice sheet covered the Patagonian Andes along 1800 km from Lat. 35ºS to 56ºS. This ice sheet reached the edge of the continental shelf west of the Andes (Pacific) south of Lat. 42ºS. Genetic diversity for the Patagonian flora and fauna might therefore be expected to reflect a hierarchy of influences, with patterns of divergence from climate change and volcanisms during the Pleistocene and Holocene layered onto ancient divergence footprints produced by the Andean orogeny. We will focus on the phylogeography of the Galaxiidae, a group of fish represented in Patagonia by three widespread species: (Galaxias platei, G. maculatus, and Aplochiton zebra) and others of more restricted geographic distribution. G. platei is a landlocked species present in the deep waters of postglacial lakes. G. maculatus and A. zebra are small littoral species with G. maculatus exhibiting landlocked and diadromous forms. Phylogeographic patterns will be compared across the three species using mitochondrial and nuclear DNA loci. The application of statistical phylogeographic and coalescent methods on genetic data collected from various species within ecosystems will provide valuable insight into the evolution of ecological communities. The diversity of the Patagonian fish fauna is threatened by competition and predation by salmonids introduced during the early twentieth century, and more recently and more critically, by escaped aquaculture salmon, the influence of which is expected to increase with the ever expanding aquaculture industry in the region. Our research will prove useful for the development of knowledge based conservation and management priorities.

我们的目标是研究巴塔哥尼亚的本地鱼类的比较地理学。安第斯山脉南部的隆起开始于中新世（约2000年）。23 MYA），分离东，西流动的排水系统，并影响相关生物群的地理格局。由此产生的地理格局随后受到更新世（1.8 MYA -10，000 BP）反复出现的冰期和间冰期以及火山活动的影响。在末次盛冰期，从拉特到沿着1800公里的巴塔哥尼亚安第斯山脉被冰盖覆盖。南纬35度至56度这片冰盖到达了拉特以南的安第斯山脉（太平洋）以西的大陆架边缘。南纬42度因此，巴塔哥尼亚植物群和动物群的遗传多样性可能反映了一种影响层次，更新世和全新世期间气候变化和火山活动的分歧模式分层到安第斯山脉产生的古老分歧足迹上。我们将集中讨论南乳鱼科的地理分布，南乳鱼科是巴塔哥尼亚的一个鱼类类群，分布广泛，有三种：斑石鳖（Aplochiton zebra）和其他地理分布较为有限的石鳖。G. platei是一个内陆物种，存在于冰后期湖泊的深水沃茨。G. maculatus和A.斑马是小型的沿岸的种，具有G.有斑点的表现出内陆的和溯河产卵的形式。将使用线粒体和核DNA位点比较三个物种的系统地理学模式。对生态系统内不同物种收集的遗传数据应用统计地理学和结合方法将为生态群落的演变提供有价值的见解。巴塔哥尼亚鱼类区系的多样性受到竞争和二十世纪初引进的鲑鱼的捕食的威胁，最近更严重的是，受到逃逸的水产养殖鲑鱼的威胁，随着该地区水产养殖业的不断扩大，其影响预计将增加。我们的研究将被证明是有用的知识为基础的保护和管理的优先事项的发展。