DISSERTATION RESEARCH: Testing Fundamental Constraints on Species Ranges in the Endemic Plant Mimulus bicolor

一个物种的分布被认为受到对环境的生理耐受性、与其他生物体的相互作用或对适应的遗传约束的限制。 在这个项目中，这些因素对适应的重要性将使用在自然特有的开花植物（Mimulus bicolor）的范围内取样的种群进行研究。植物种群将在具有不同降水和温度制度的生长室中生长，以确定植物适应性是否受到对范围边缘预期环境的生理耐受性的限制。 通过研究种群遗传多样性的模式来推断遗传约束对适应的作用，以确定范围边缘的种群是否有效地很小，本质上是孤立的，或者从物种范围中心的种群中经历适应不良的基因流。 了解限制物种分布的机制将提高我们预测物种分布在气候变化面前如何变化的能力。 除了回答这个广泛的问题外，该研究还将训练一名研究生和一名本科生在受控环境中进行实验，并使用遗传标记来确定种群结构和基因流动模式。 这些方法中的每一种都将提供有关物种分布范围限制的关键信息，并可用于未来有关物种分布范围变化的管理决策。学生将在研究会议上展示他们的工作，并将他们的发现传播给其他科学家和研究人员。

The distribution of a species is thought to be limited by physiological tolerances to the environment, interactions with other organisms, or genetic constraints on adaptation. In this project the importance of these factors on adaptation will be studied using populations sampled across the range of a naturally endemic flowering plant (Mimulus bicolor). Plant populations will be grown in growth chambers with varying precipitation and temperature regimes to determine whether plant fitness is limited by physiological tolerances to environments expected at the range edge. The role of genetic constraints on adaptation will be inferred by studying patterns of population genetic diversity to determine whether populations at range edges are effectively small, inherently isolated, or experience maladaptive gene flow from populations at the center of the species range. Understanding the mechanisms that limit the distribution of species will increase our ability to predict how the distribution of species will shift in the face of climate change. In addition to answering this broad question, the research will train a graduate student and undergraduate students to conduct experiments in controlled environments and to use genetic markers to determine population structure and patterns of gene flow. Each of these approaches will provide critical information on species range limits and can be used for future management decisions regarding species range shifts. Students will present their work at research meetings, which will disseminate their findings to other scientists and researchers.