Molecular phylogeny and speciation in a regional fauna

我的研究计划的目标是：(1)记录自然种群内部和之间的进化分化模式，(2)检验关于生物多样性从独特种群到物种起源的假设，(3)将这种理解应用于生物多样性的保护。用于解决进化生物学中这些关键问题的模型是北美西北部的鱼类，包括：在不同的冰川避难所中分离出来的进化谱系（棘鱼、鳟鱼和鲑鱼）；通过自然地貌（如鳟鱼、鲑和灰鲑的迁移障碍、流域互联性）或生态（鳟鱼和棘鱼对不同栖息地的适应）表现出不同程度物理分离的种群；以及冰期后接触到的近亲鱼类（棘鱼和棘鱼）。该研究项目的新颖之处包括：整合历史和当代的分化过程，对这些过程在旧的（如char）和最近的（如棘鱼）分化中的比较分析，以及在假设检验中整合分子和生态方法。例如，分子系统发育学、种群遗传学和生态学方法都被整合到对北美西北部两种鱼类（多利瓦尔登和牛鳟）之间形成接触带的历史因素的研究中，以及确定接触带当前遗传结构的过程。这项工作的重要性，以及对棘鱼的相关工作，包括了解影响种群内和种群间遗传变异的过程（如自然选择、遗传漂变和基因流之间的相互作用），以及促进新物种进化的生态和遗传过程。总的来说，所有这些影响都与帮助理解生物多样性的起源高度相关——这是进化生物学的一个基本目标，也是保护生物多样性的必要先决条件。我们的工作对培养加拿大急需的水生和分子生态学以及生物多样性研究领域的年轻科学家也很重要。

The goals of my research program are to: (i) document the patterns of evolutionary divergence within andamong natural populations, (ii) test hypotheses concerning the origins of biodiversity from unique populationsto species, and (iii) apply such understanding to the conservation of biodiversity. The models used to addressthese key questions in evolutionary biology are fishes of northwestern North America, including: evolutionarylineages that were isolated in distinct glacial refugia (sticklebacks, trout, and char); populations that showvarious degrees of physical separation via physical landform (e.g., migration barriers, watershedinterconnectedness in trout, char, and grayling) or ecology (adaptation to distinct habitats in trout andsticklebacks); and species of closely related fishes that have come into contact (char and sticklebacks)postglacially. The novel aspects of this research program include: integration of historical and contemporaryprocesses in divergence, comparative analyses of these processes in old (e.g., char) and more recent (e.g.,sticklebacks) divergences, and the integration of molecular and ecological methods in hypothesis testing. Forinstance, molecular phylogenetic, population genetic, and ecological methods have all been integrated into thestudy of the historical factors that were involved in the formation of a contact zone between two char, DollyVarden and bull trout, in northwestern North America, and the processes that determine the current geneticstructure of the contact zone. The significance of this work, and related work on sticklebacks, includesunderstanding the processes (such as the interactions among natural selection, genetic drift, and gene flow)that influence genetic variation within and between populations, and the ecological and genetic processes thatpromote the evolution of new species. Most generally, all of these impacts are highly relevant to helping tounderstand the origins of biodiversity - a fundamental goal of evolutionary biology as well as a necessarypre-requisite to the conservation of biodiversity. Our work is also important for the training of young scientistsin areas of great need for Canada - aquatic and molecular ecology and biodiversity research.