Molecular and evolutionary ecology of species' geographical distributions

所有物种的地理分布都是有限的——从只在富氧环境中生存的细菌到只生活在世界一个小角落的植物。什么样的生物因素（即历史、生态和遗传学）决定了一个物种能在哪里生存，不能在哪里生存，这是当今生物学家和自然资源保护主义者面临的一个经久不衰但尚未解决的问题。一方面，我们寻求在未来全球化和气候情景下预测和管理动植物的分布。另一方面，我们面临的挑战是了解决定物种当前分布的关键因素。最终，一个物种只可能出现在与其基因构成相容的栖息地，也就是说，它所适应的环境。这是一个物种的地理分布及其与生态环境相互作用的遗传基础，我的研究将解决。我们对与地理分布相关的因素的许多期望是基于完善的，但很少经过测试的理论模型。我的研究将以我目前的记录为基础，测试植物适应和地理分布的生态学和遗传学。我将评估生境和散布与中性和功能性（即重要的适合度）遗传变异在海岸沙丘植物中的相互作用。蕨类植物（芸苔科），海火箭，是海滩和沙丘植物区系的重要成员，具有长距离扩散的能力，分布在北美东部和西部海岸线。现代分子技术、野外生物学和实验操作的结合将为教学和发现提供极好的机会。

All species have limits to their geographical distributions - from the bacteria that survive only in oxygen rich environments to the plant that lives only in one small corner of the world. What biological factors (i.e. history, ecology and genetics) determine where a species can and cannot survive is an enduring yet unresolved question facing biologists and conservationists today. On the one hand, we seek to predict and manage the distributions of plants and animals under future globalization and climatic scenarios. On the other hand, we are tasked with the challenge of understanding the key factors that determine species' current distributions. Ultimately, a species may only occur in habitats that are compatible with its genetic make-up, that is, the environments to which it is adapted. It is the genetic basis to a species' geographic distribution and its interaction with ecological environments that my research will address. Many of our expectations for the factors associated with geographical distributions are based on well established, but infrequently tested theoretical models. My research will build on my current record of testing the ecology and genetics of adaptation and geographical distributions in plants. I will assess the interplay of habitat and dispersal with neutral and functional (i.e. important for fitness) genetic variation in a coastal dune plant. Cakile edentula (Brassicaceae), sea rocket, is a charismatic and important member of the beach and dune flora, has the ability for long distance dispersal, and occurs along both eastern and western North American coastlines. The combination of modern molecular techniques, field biology and experimental manipulations that characterize the research proposed here will provide an excellent opportunity for teaching and discovery.