Intraspecific biodiversity of fishes and their monogenean parasites: pattern and process

鱼类及其单殖寄生虫的种内生物多样性：模式和过程

• 批准号: 249682-2012
• 负责人: Bentzen, Paul
• 金额: $ 1.89万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=547359
• 关键词: Intraspecific; biodiversity; fishes; their; monogenean

My research investigates biological diversity within species in aquatic environments. I am trying to answer three general questions: (1) How connected are populations? (2) How much adaptive genetic diversity exists within species, and what are some of the key processes generating it? (3) When, and by what ecological processes does genetic diversity within species reach the point in which populations are actually distinct species? My approach to answering these questions includes paired population genetic analyses of fishes and their monogenean parasites. The parasites are included for the following reasons: First, their host specificity suggests that their population structure should mirror that of their fish hosts, but their smaller effective population sizes and very short generation times lead to the prediction that they will actually show much more genetic structure than their hosts; thus, they have the potential to act as "biological magnifying glasses" revealing cryptic details of their host fish population structure. Second, these parasites, which belong to the genus Gyrodactylus, are believed to have diversity rivalling that of fishes, and they are ecologically and at times economically important (because of their impacts on some wild and aquacultured fish populations), yet almost nothing is known about their intraspecific diversity; thus, they deserve study in their own right. I am using 'genome scans' based on advanced DNA sequencing techniques to identify genomic regions in both the fishes and their parasites that show adaptive genetic variation, and that, in some cases, are associated with the development of new species. Several fish species, including sticklebacks, Atlantic Cod, guppies, Rainbow Smelt (and their parasites), will serve as experimental models for this research, but the results should provide general insights into the patterns and extent of intraspecific biodiversity in aquatic environments, and the ecological and evolutionary processes that underlie it. They will also help inform conservation and management efforts. This research program will lead to the training of a number of young scientists in advanced methods of genomic analysis and in aquatic biodiversity, both areas of importance to Canada.

我的研究是调查水生环境中物种的生物多样性。我试图回答三个一般性问题：(1)人口之间的联系有多紧密？(2)物种内部存在多少适应性遗传多样性？产生适应性遗传多样性的一些关键过程是什么？(3)物种内部的遗传多样性何时以及通过何种生态过程达到种群实际上是不同物种的程度？我回答这些问题的方法包括对鱼类及其单系寄生虫的配对种群遗传分析。寄生虫被纳入研究的原因如下：首先，它们的宿主特异性表明它们的种群结构应该反映它们的鱼类宿主，但它们较小的有效种群规模和非常短的世代时间导致预测它们实际上会比它们的宿主显示更多的遗传结构；因此，它们有可能充当“生物放大镜”，揭示其宿主鱼类种群结构的神秘细节。其次，这些寄生虫，属于Gyrodactylus属，被认为具有与鱼类相媲美的多样性，它们在生态上和有时在经济上都很重要（因为它们对一些野生和养殖鱼类种群的影响），但对它们的种内多样性几乎一无所知；因此，它们本身就值得研究。我正在使用基于先进DNA测序技术的“基因组扫描”来识别鱼类及其寄生虫中显示适应性遗传变异的基因组区域，在某些情况下，这些区域与新物种的发展有关。包括刺鱼、大西洋鳕鱼、孔雀鱼、彩虹臭鱼（及其寄生虫）在内的几种鱼类将作为本研究的实验模型，但研究结果应提供对水生环境中种内生物多样性的模式和程度以及其背后的生态和进化过程的一般见解。它们还将有助于为保护和管理工作提供信息。这一研究项目将在基因组分析和水生生物多样性的先进方法方面培训一批年轻科学家，这两个领域对加拿大都很重要。