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

由于快速而强烈的人为环境变化，包括传染病的传播、外来物种和入侵物种的引入以及全球变暖，野生动物种群日益受到新的和强大的选择压力的挑战。同时，人类活动正在迅速移走或碎片化栖息地，导致种群数量下降，并限制种群之间的遗传交流。这些因素加在一起，可能会限制种群的适应能力，降低个体的适应性，并最终危及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异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萨布尔岛国家公园保护区的一项长期的、基于个体的野马研究作为模型，来测试各种新兴的假说，这些假说与野生动物健康相关特征的遗传基础和进化动态有关。Sable Island马项目以其他非常成功的基于个体的研究为蓝本，例如在艾伯塔省的Ram Mountain(大角羊)和苏格兰的St-Kilda(Soay绵羊)的研究，在许多方面都是值得注意的。特别是，该系统允许研究大量和多样化的被认为与适应度有关的表型特征；与世隔绝但庞大的种群(当前种群规模约为500)提供了快速测试新想法所需的统计能力；以及随时可用的马基因组工具为在自然条件下进行基因组研究提供了一个出色的平台。自2008年以来，每年夏天都有近1150名已知个体对各种与健康相关的特征进行测量，这项研究已经是世界上大型脊椎动物同类研究中规模最大的之一。我提议的研究分为四个短期目标，有助于实现我的主要职业目标，即提高我们对生态和进化过程的理解，调节野生动物种群适应性和适应性进化的变异。我将采用一种综合的、多学科的方法，结合田间生物学、分子生态学、寄生虫学、数量遗传学和基因组学，我将：i)对肠道细菌微生物群结构和功能变异的原因和后果进行大规模调查；ii)研究复杂混合寄生虫感染的生态和进化；iii)表征与适应相关的性状和适应性进化的基因组结构；以及iv)量化近亲繁殖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发展国际公认的野生动物进化和生态遗传学研究计划，并为加拿大和国际上保护和管理野生动物和濒危物种提供所需的工具和知识。

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.