Dissertation Research: The Evolutionary Impact of Natural Selection, Quantitative Genetic Variation, and Gene Flow in a Salt Marsh Perennial, Limonium carolinianum

测量理论和统计学的最新发展 自然选择允许选择作用于 表型与遗传分开测量， 表型和自然选择对表型的估计 特质已经被用来解决许多当代理论 植物生物学的问题。 用盐做的实验 沼泽植物加州补血草（Limonium carolinianum） 选择生殖性状，并解决三个关键问题 更全面地了解选择估计， 野生种群对自然选择的基因型反应：1） 了解的遗传基础和遗传性的 数量性状被测量用于选择估计，2） 邻域参数，这些参数确定了 选择可以通过控制平衡来引起适应性变化 自然选择和随机遗传 漂移，3）环境的实验操作，可以 确定偶然的选择性代理人或部分解释原因 选择以观察的方式进行。 局部变自然数 自然选择、随机遗传漂变和有限的基因流动都是 在植物适应当地环境中起着重要作用 人口。 然而，空间尺度的同时估计 选择，数量的遗传变异， 社区的大小和面积从来没有 在野生植物中获得。 这项研究将有助于 更好地了解植物种群变化的敏感和 盐沼生态系统的萎缩

Recent developments in the theory and statistics for measuring natural selection have allowed the action of selection on the phenotype to be measured separately from the inheritance of that phenotype and these estimates of natural selection on phenotypic traits have been used to address many contemporary theoretical issues in plant biology. The proposed experiments with the salt marsh plant Limonium carolinianum would provide measures of selection on reproductive traits and address three issues crucial to a more complete understanding of selection estimates and genotypic responses to natural selection in wild populations: 1) understanding the genetic basis and heritability of the quantitative traits being measured for selection estimates, 2) neighborhood parameters that determine the spatial scale over which selection could cause adaptive change by and control the balance between such change by natural selection or by random genetic drift, 3) experimental manipulation of environment that can identify the casual selective agents or partially explain why selection operates in an observed way. Locally variable natural selection, random genetic drift, and limited gene flow are all believed to play major roles in the local adaptation of plant populations. However, simultaneous estimates of the spatial scale of selection, amount of quantitative genetic variation available to respond to selection, and neighborhood size and area have never been obtained in a wild plant species. The study will contribute to better knowledge of plant population change in sensitive and shrinking salt-marsh ecosystems.