Molecular phylogeny and speciation in a regional fauna

区域动物群的分子系统发育和物种形成

• 批准号: RGPIN-2018-03926
• 负责人: Taylor, Eric
• 金额: $ 4.53万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=691143
• 关键词: Molecular; phylogeny; speciation; regional; fauna

The central goal of my research program is to understand the origins and persistence of biodiversity at multiple spatial and temporal scales - from allelic variation at specific genetic loci to the assemblage of species at a biogeographic scale, and divergences spanning a few generations to millions of years. The long-term themes of my research program are to: (i) document the patterns of evolutionary divergence within and among species, (ii) test hypotheses concerning the origins and persistence of this variation and the relevance of processes such natural selection, hybridization, and vicariance, and (iii) to apply this knowledge to the conservation of biodiversity. I study freshwater and marine fishes in northwestern North America and the Arctic and integrate methods in ecology and genetics to address these central inquiries in organismal and evolutionary biology that also have important conservation applications. My research poses questions such as: what are the interrelationships amongst species within a clade and what biogeographic processes (e.g., tectonics, sea level changes, climate change) have shaped extant diversity? When species come into contact, do they hybridize and if so, what can the frequency and fate of hybrids tell us about the geographic, ecological and genetic processes driving speciation? What habitat features influence the extent and patterns of adaptive and neutral variation among conspecific populations? The key theme of this proposal examines species that come into contact to test hypotheses concerning the genome-wide extent of hybridization and the genetic basis of reproductive isolation. I exploit the occurrence of multiple areas of contact between two species of Salvelinus, S. alpinus (Arctic char) and S. malma (Dolly Varden) in western Alaska. I will build on our detailed nuclear DNA microsatellite analyses demonstrating contact and hybridization between these species by using genomic sequencing approaches to better pinpoint the extent and specific regions of the genome that distinguish these species in the face of gene flow. This work will also explore the hypothesis of life history character displacement by exploiting the occurrence of multiple allopatric and sympatric populations of both species which express the full range of freshwater resident and anadromous (searun) life histories. The significance and novelty of my research includes:(1) understanding a fundamental unknown in evolution (the origins and persistence of biodiversity),(ii) providing much needed training in biodiversity research in Canada, (iii) illustrating the intimate connection between habitat and biodiversity persistence critical for conservation assessment and action, and (iv) providing some emphasis for (i)-(iii) in northern areas which are relatively understudied and at increasing risk in Canada from environmental change.

我的研究计划的中心目标是了解多个空间和时间尺度上生物多样性的起源和持久性 - 从特定遗传位点的等位基因变异到生物地理尺度上的物种组合，以及跨越几代到数百万年的分歧。我的研究计划的长期主题是：（i）记录物种内部和物种之间的进化分化模式，（ii）测试有关这种变异的起源和持续性的假设以及自然选择、杂交、和替代性，以及 (iii) 将这些知识应用于保护生物多样性。我研究北美西北部和北极的淡水和海洋鱼类，并整合生态学和遗传学方法来解决有机体和进化生物学中的这些中心问题，这些问题也具有重要的保护应用。我的研究提出了这样的问题：一个分支内物种之间的相互关系是什么，以及哪些生物地理过程（例如构造、海平面变化、气候变化）塑造了现存的多样性？当物种接触时，它们会杂交吗？如果是的话，杂交的频率和命运可以告诉我们关于驱动物种形成的地理、生态和遗传过程的什么信息？哪些栖息地特征影响同种种群之间适应性和中性变异的程度和模式？该提案的关键主题是检查接触的物种，以测试有关全基因组杂交范围和生殖隔离遗传基础的假设。我利用了阿拉斯加西部两种红点鲑（S. alpinus）（北极红点鲑）和红点鲑（Dolly Varden）之间的多个接触区域。我将在详细的核 DNA 微卫星分析的基础上，通过使用基因组测序方法来证明这些物种之间的接触和杂交，以更好地查明在基因流中区分这些物种的基因组范围和特定区域。这项工作还将通过利用两个物种的多个异域和同域种群的出现来探索生活史特征位移的假设，这些种群表达了淡水居民和溯河产卵（searun）生活史的全部范围。我的研究的意义和新颖性包括：（1）了解进化中的一个基本未知（生物多样性的起源和持久性），（ii）为加拿大的生物多样性研究提供急需的培训，（iii）说明栖息地和生物多样性之间的密切联系。生物多样性的持久性对于保护评估和行动至关重要，并且 (iv) 为北部地区的 (i)-(iii) 提供一些重点，这些地区的研究相对较少，并且在加拿大面临越来越大的环境变化风险。