Evolutionary and ecological genetics of fitness-related variation in wild animals

快速而强烈的人为环境变化，包括传染病的传播、外来和入侵物种的引入以及全球变暖，导致野生动物种群日益受到新的、强大的选择压力的挑战。与此同时，人类活动正在迅速消除或破坏栖息地，导致种群数量下降并限制种群之间的基因交换。这些因素加在一起会限制种群的适应能力，降低个体的适应性，并最终损害种群和物种的持久性。因此，了解调节自然种群适应性和适应性进化变化的生态和进化过程对于维持生物多样性至关重要。在这里，我建议使用新斯科舍省塞布尔岛国家公园保护区的野马的长期、基于个体的研究作为模型来测试与野生动物健康相关性状的遗传基础和进化动力学相关的各种新假设。塞布尔岛马项目以其他非常成功的个体研究为蓝本，例如阿尔伯塔省拉姆山（大角羊）和苏​​格兰圣基尔达（索伊羊）的研究，在许多方面都引人注目。特别是，该系统允许研究大量且多样的与健康相关的表型特征；孤立但庞大的人口（当前人口规模约 500 人）提供了快速测试新想法所需的统计能力；易于使用的马基因组工具为在自然条件下进行基于基因组的研究提供了一个出色的平台。自 2008 年以来，该研究每年夏天都会对近 1,150 名已知个体的各种健康相关特征进行测量，该研究已经是世界上针对大型脊椎动物进行的最大的同类研究之一。我提出的研究分为四个短期目标，有助于我的主要职业目标，即提高我们对调节野生动物种群适应性和适应性进化变化的生态和进化过程的理解。使用结合现场生物学、分子生态学、寄生虫学、定量遗传学和基因组学的综合、多学科方法，我将： I) 对肠道细菌微生物组结构和功能变异的原因和后果进行大规模研究； II) 研究复杂混合寄生虫感染的生态学和进化； III) 表征适应性相关性状和适应性进化的基因组结构； IV) 量化近交抑制并了解调节其强度和遗传结构的因素。拟议的研究将有助于制定国际公认的野生动物进化和生态遗传学研究计划，并提供加拿大和国际上保护和管理野生动物和濒危物种所需的工具和知识。

Wildlife populations are increasingly challenged by new and strong selective pressures resulting from rapid and intense anthropogenic environmental change, including the spread of infectious diseases, introduction of exotic and invasive species, and global warming. Simultaneously, human activity is rapidly removing or fragmenting habitat, leading to population declines and restricting genetic exchange among populations. Together, these factors can limit the ability of populations to adapt, decrease individual fitness, and ultimately compromise the persistence of populations and species. Understanding the ecological and evolutionary processes modulating variation in fitness and adaptive evolution in natural populations is therefore critical for maintaining biodiversity. Here, I suggest using a long-term, individual-based study of feral horses at Sable Island National Park Reserve, Nova Scotia, as a model to test a variety of emerging hypotheses related to the genetic basis and evolutionary dynamics of fitness-related traits in wild animals. The Sable Island horse project, modelled on other highly successful individual-based studies such as those at Ram Mountain in Alberta (bighorn sheep) and St-Kilda in Scotland (Soay sheep), is remarkable in a number of ways. In particular, the system allows for the study of a large and diverse array of phenotypic traits putatively linked to fitness; the isolated but large population (current population size ~500) provides statistical power needed to rapidly test new ideas; and readily available equine genomic tools makes for an outstanding platform to conduct genomic-based research under natural conditions. With almost 1,150 known individuals measured at a variety of fitness-related traits each summer since 2008, the study is already one of the world's largest of its kind for a large vertebrate. My proposed research is divided into four short-term objectives contributing to my principal career goal of improving our understanding of the ecological and evolutionary processes modulating variation in fitness and adaptive evolution in wildlife populations. Using an integrative, multi-disciplinary approach combining field biology, molecular ecology, parasitology, quantitative genetics, and genomics, I will: I) Conduct a large-scale investigation of the causes and consequences of variation in gut bacterial microbiome structure and function; II) Study the ecology and evolution of complex mixed parasitic infections; III) Characterize the genomic architecture of fitness-related traits and adaptive evolution; and IV) Quantify inbreeding depression and understand the factors modulating its intensity and genetic architecture. The proposed research will contribute to developing an internationally recognized research program in evolutionary and ecological genetics of wild animals, and provide tools and knowledge needed for conserving and managing wildlife and endangered species in Canada and internationally.