Evolutionary History of Arctic Biomes

生物多样性提供了无价的生态系统服务，如清洁的水、授粉和食物，但它面临着来自气候变化、污染、栖息地丧失和入侵物种的前所未有的威胁。我的研究计划的目标是在全球变化的背景下了解生物多样性的进化历史、当前的多样性和分布以及未来。由于北极在过去两百万年中经历了多次冰川周期，北极生物群是研究剧烈环境变化对生物多样性影响的绝佳机会。在我们对北极生物多样性的理解中，一个关键的差距是扩散和进化在生物群形成中的作用。目前的模式是，在覆盖北美北部大部分地区的冰川冰盖消退之后，生活在南部无冰区(避难所)和西北部(阿拉斯加和育空)的生物重新定居北极。然而，最近由DNA序列数据提供信息的研究表明，这种主要基于对植物和脊椎动物的研究的观点可能过于简单。相反，我们在加拿大中部高北极地区的研究发现了独特的无脊椎动物物种和一些物种的高度遗传多样性。这些模式表明，北极高地避难所的一些种群可能持续占领了北极，来自多个避难所的种群混合在一起，以及独特的北极生命形式的演变。这项研究计划将调查避难所的扩散、生物学特征和北方进化的相对作用。我们将在加拿大西部北极地区进行实地工作，这是一个分子生物多样性研究不足的地区，并将重点关注淡水无脊椎动物。我们将产生关于物种多样性、遗传和基因组多样性、进化关系、栖息地占用和营养水平等生态特征的新知识。然后，我们将把这些新数据与来自其他地理区域的公开信息结合起来，量化从南部地区扩散、人口混合以及北极演化和多样化的重要性，这可能会改变我们对北极生物多样性起源的理解。这项工作的应用包括预测由于气候变化引起的物种地理范围的变化，为管理工作提供信息，对生态系统健康进行生物监测，以减轻与自然资源行业(如采矿)相关的环境风险，以及开发基于DNA的潜在入侵或致病物种快速检测系统。该研究计划将培养3名硕士(论文)、3名生物信息学硕士(课程和主要研究项目)、3名博士、5名本科生和3名北方学生。该计划将有助于满足在生物科学、数据分析和在北方工作的员工的需求，以造福加拿大的经济和环境。

Biodiversity provides invaluable ecosystem services, such as clean water, pollination, and foods, yet it is facing unprecedented threats from climate change, pollution, habitat loss, and invasive species. The goals of my research program are to understand the evolutionary history, current diversity and distributions, and future of biodiversity in the context of global change. Due to the multiple glacial cycles the Arctic has experienced over the past two million years, the Arctic biome represents an outstanding opportunity to study the influence of dramatic environmental change on biodiversity. A key gap in our understanding of Arctic biodiversity is the role of both dispersal and evolution in biome formation. The current paradigm is that, following the retreat of the glacial ice sheets covering most of northern North America, the Arctic was recolonized by organisms living in ice-free areas (refugia) to the south and in the Northwest (Alaska and Yukon). However, recent research informed by DNA sequence data suggests that this view, mainly based on studies of plants and vertebrates, may be too simple. Our research in the central Canadian high Arctic has instead found unique species of invertebrates and high genetic diversity within some species. These patterns suggest that there may have been sustained occupancy of the North by some populations in high-Arctic refugia, mixing of populations from multiple refugia, and the evolution of unique Arctic life forms. This research program will investigate the relative roles of dispersal from refugia, biological traits, and evolution in the North. We will conduct field work in the Western Canadian Arctic, an understudied region for molecular biodiversity, and will focus upon freshwater invertebrates. We will generate new knowledge of species diversity, genetic and genomic diversity, evolutionary relationships, habitat occupancy, and ecological traits such as trophic level. We will then combine these new data with publicly available information from other geographic regions to quantify the importance of dispersal from southern areas, mixture of populations, and Arctic evolution and diversification, potentially transforming our understanding of the origins of Arctic biodiversity. Applications of this work include predicting geographic range shifts of species due to climate change to inform management efforts, biomonitoring for ecosystem health to mitigate environmental risks associated with natural resource industries (e.g. mining), and developing rapid DNA-based detection systems for potentially invasive or pathogenic species. This research program will train 3 MSc (thesis), 3 Master of Bioinformatics (coursework plus major research project), 3 PhD, 5 undergraduate, and 3 Northern students. This program will help to address the need for employees with training in biological sciences, data analysis, and working in the North for the benefit of Canada's economy and environment.