DISSERTATION RESEARCH: The role of selection, gene flow, and range limits in determining adaptive phenotypes

物种范围的限制可以是适应多样性高或低的区域，这取决于遗传变异、自然选择的强度以及来自附近种群的基因流的数量和性质。在这项研究中，本研究通过田间实验了解基因流动和选择在内华达山脉一年生植物Mimulus laciniatus适应性多样性中的作用，该植物的地理范围有限。初步数据揭示了低海拔和高海拔范围限制下的气候适应情况。沿着这些范围限制确定选择的性质的实验正在进行中，而实验配对将提供对来自远近种群的基因流对范围边缘适应潜力的作用的理解。最后，遗传标记(微卫星)正被用来估计物种范围内的基因流和种群大小。除了提供关于范围限制下的进化的基本见解外，这项研究还将在气候变化导致栖息地日益温暖的时候为物种管理和保护工作提供信息。山地系统拥有令人印象深刻的多样性的植物物种。发展对遗传多样性、基因流动和气候适应如何相互作用的理解，可能有助于更广泛地制定旨在保护这些独特植物区系的战略。此外，该项目继续支持本科生，包括许多科学界代表性不足的群体的成员；学生作为研究助理参与，并经常开发自己的独立研究项目。

Species range limits can be areas of high or low adaptive diversity depending on genetic variation, the strength of natural selection, and the amount and nature of gene flow from nearby populations. In this study, field experiments are used to understand the role of gene flow and selection in the adaptive diversity of Mimulus laciniatus, a Sierra Nevada annual plant with a restricted, well-defined geographic range. Preliminary data reveal climate adaptations at low- and high-elevation range limits. Experiments to determine the nature of selection along these range limits are ongoing while experimental matings will provide an understanding of the role of gene flow, from both far and nearby populations, on adaptive potential at range edges. Finally, genetic markers (microsatellites) are being used to estimate gene flow and population sizes across the species range. In addition to providing basic insights about evolution at range limits, this research will inform species management and conservation efforts at a time when climate change is resulting in increasingly warmer habitats. Mountain systems host an impressive diversity of plant species. Developing an understanding of how genetic diversity, gene flow, and climate adaptation interact may contribute to strategies aimed more broadly at conserving these unique floras. Additionally, this project continues to support undergraduates, including many members of underrepresented groups in science; students participate as research assistants and often develop their own independent research projects.