Origins, maintenance, and loss of biodiversity

我的研究项目侧重于与生物多样性的起源、维持和丧失相关的因素。引进物种是对当地生物多样性的重大威胁，但我们往往不知道它们入侵的遗传基础，也不知道它们如何对当地物种产生负面影响。拟议的研究将：(I)重建有毒物种(信号小龙虾)传播的历史路线；(Ii)记录信号小龙虾对三刺鱼的影响；以及(Iii)提高我们对皮肤粗糙的Newt毒素产生的了解。为了实现这些目标，我们将结合现场和基于实验室的方法。在三个目标中：*(I)通过使用中性遗传标记*经历范围扩张的物种的种群遗传学*，我们的目标是查明入侵物种的身份和起源，并表征它如何在空间和时间上传播到目前的范围限制。Signal小龙虾原产于不列颠哥伦比亚省大陆，但在温哥华岛上似乎一直没有出现，直到上个世纪之交，它与一对独特的湖栖三刺鱼物种的丧失有关。*(Ii)不列颠哥伦比亚省海岸捕食者对当地物种的进化影响*三刺鱼在不列颠哥伦比亚省海岸对年轻物种适应的速度和模式有了许多见解，但受到入侵物种的威胁。为了更好地了解对独居的三刺鱼种群的威胁，我们将描述引进物种的生态和进化影响。具体地说，我们将描述生活在有/没有信号小龙虾的种群生态的不同方面，目的是确定可能面临当地灭绝风险的种群。*(Iii)本地毛皮纽带蛇产生毒素的遗传基础*本地毛皮纽带蛇捕食各种物种，包括本地毛皮蝾螈，它拥有与致命的河豚鱼相同的毒素(河豚毒素)。尽管蛇与蝾螈的相互作用对于我们理解共同进化很重要，但我们对蝾螈产生毒素的遗传基础知之甚少。我们将使用分子方法来确定遗传密码的哪些部分用于产生这种毒素。在相关的调查中，我们调查了信号小龙虾的传播是否与不列颠哥伦比亚省海岸的纽特毒素水平的变化有关。*入侵物种在加拿大所有主要地区都是一个重要的和日益增长的问题，这项研究计划将促进我们对入侵物种的生态和进化及其对两个本地物种的影响的理解。该研究计划还将为14名高素质人员(2名博士生、3名硕士学生和9名本科生项目学生)提供培训机会，使他们在生命科学领域的职业生涯中具有竞争力。

My research program focuses on factors associated with the origins, maintenance and loss of biodiversity. Introduced species are a significant threat to native biodiversity, yet we often do not know about the genetic basis of their invasiveness or how they negatively impact native species. The proposed research will: (i) reconstruct historical routes of spread in a noxious species (signal crayfish); (ii) document effects of signal crayfish on threespine stickleback; and (iii) improve our understanding of toxin production in the rough-skinned newt. To achieve these goals, we will combine field and lab-based methods. Within the three objectives:******(i) Population genetics of species experiencing range expansions***By using neutral genetic markers, we aim to pinpoint the identity and origins of an invasive species, and characterize how it spread through space and time to its current range limits. Signal crayfish is native to mainland British Columbia, but appears to have been absent from Vancouver Island until the turn of the last century, where it is implicated in the loss of a unique pair of lake-dwelling threespine stickleback species.***(ii) Evolutionary effects of predators on native species***Threespine stickleback on the coast of British Columbia have yielded many insights into the pace and mode of adaptation in young species, but are under threat from invasive species. To better understand threats to solitary threespine stickleback populations, we will characterize ecological and evolutionary impacts of introduced species. Specifically, we will characterize various aspects of the ecology of populations living in the presence/absence of signal crayfish, with the goal of identifying populations potentially at risk of local extinction.***(iii) Genetic basis of toxin production in the rough-skinned newt***Native garter snakes prey upon a variety of species, including the native rough-skinned newt, which possesses the same toxin (tetrodotoxin) that is found in the deadly fugu puffer fish. Despite the importance of the snake-newt interaction for our understanding of coevolution, we know very little about the genetic basis of toxin production in newts. We will use molecular methods to determine which parts of the genetic code are used to produce this toxin. In related investigations, we investigate whether the spread of signal crayfish is associated with changes in newt toxin levels along the coast of British Columbia.******Invasive species are a significant and growing concern in all major regions of Canada, and this research program will advance our understanding of the ecology and evolution of an invasive species and its effects on two native species. The research program will also provide training opportunities for 14 highly qualified personnel (two PhD students, three MSc students, and nine undergraduate project students), making them competitive for careers in the life sciences.