Intraspecific diversity and conservation biology of fishes

我的研究项目使用各种方法来研究淡水和海洋鱼类的种内生物多样性，特别是那些出现在大西洋加拿大的鱼类。我们使用线粒体DNA的DNA测序来了解多样性的历史组成部分-例如，追溯当代人口到他们在冰河时代占据的冰川避难所。我们研究更快速进化的序列，称为微卫星，以衡量物种现在分裂成种群的程度，种群之间进行了多少混合或扩散，并确定种群内存在多少遗传变异。我们研究鱼类的特定基因，以确定它们是否表现出局部适应。我们研究身体形态，以考察种群在生态适应方面的不同。我们使用常见的花园实验来测试当地鱼类种群在它们的适应方面是否表现出差异，例如，它们抵御常见环境压力的能力，如酸性(低pH值)，也测试种群内的近亲交配量是否影响鱼类耐受低pH值等压力的能力。我们研究各种鱼类，包括但不限于彩虹鱼、湖白鱼、狼和美国阴影。我研究种内生物多样性是为了获得有价值的基础知识，但也是因为它对保护很重要。作为一个北部国家，加拿大的大部分地区在冰河时代被冰川覆盖，与世界上较温暖的未冰川地区相比，加拿大的物种相对较少，但其物种分为无数种群，这些种群往往相当不同。物种内的这种多样性是加拿大和其他地方总生物多样性的重要组成部分。认识到物种内部的多样性很重要，因为了解种内生物多样性是保护物种的重要第一步。保护种内生物多样性很重要，因为它有助于生态系统的功能，是我们自然遗产的一部分，并提供了使物种能够适应未来环境变化的变异储藏库。

My research program uses a variety of methods to examine the intraspecific biodiversity of freshwater and marine fishes, especially those that occur in Atlantic Canada. We use DNA sequencing of mitochondrial DNA to learn about historical components of diversity - for example, to trace contemporary populations back to the glacial refugia they occupied during the ice ages. We study more rapidly evolving sequences, called microsatellites, to measure the extent to which species are split into populations now, how much mixing or dispersal goes on between populations, and to determine how much genetic variation exists within populations. We study particular genes in fishes to determine if they show local adaptations. We study body morphology to examine how populations differ in their ecological adaptations. We use common garden experiments to test whether local populations of fishes show differences in their adaptations, for example, in their ability to withstand common environmental stresses such as acidity (low pH), and also to test whether the amount of inbreeding within populations affects the ability of fish to tolerate stresses such as low pH. We study a variety of fish species, including but not limited to rainbow smelt, lake whitefish, wolffishes, and American shad.I study intraspecific biodiversity to gain valuable fundamental knowledge, but also because it is important for conservation reasons. As a northern country, much of which was covered by glaciers during the ice ages, Canada has relatively few species compared to warmer unglaciated parts of the world, but its species are divided into a myriad of populations, and these populations are often quite diverse. This diversity within species is a substantial part of the total biodiversity in Canada and elsewhere. It is important to recognize diversity within species, because understanding intraspecific biodiversity is an essential first step towards conserving it. It is important to conserve intraspecific biodiversity, because it contributes to the functioning of ecosystems, is part of our natural legacy, and provides the reservoir of variation that allows species to adapt to future environmental changes.