Dissertation Research: Ecological Genetics of Life-history Evolution in Mimulus guttatus

生物学的一个中心目标是了解促成生命多样性的生态和遗传因素。对不同生态条件的适应是通过基因组和可见特征的变化来实现的。很少有研究分析差异背后的基因组差异。该项目旨在回答有关两个截然不同的野生牙根水母种群之间的适应差异的基本问题。一个种群由生活在极端高山条件下的微小的、开着小花的一年生植物组成。其他种群包括居住在沿海温带环境的沙丘上的多年生大花植物。这项研究将使用基因组图谱方法来识别和表征常见花园环境中性状差异的遗传基础。此外，这项实验将揭示特定的基因类型在不同的自然环境中如何表现出适合性。通过在相互移植实验中分析重组自交系(一年生和多年生之间的高级世代杂交种)，将评估与两种自然环境中的特定基因组区域相关的适应度差异。这种对局部适应的遗传解剖将有助于澄清哪些特征和染色体区域与野外表现有关。这些实验的结果将提供对基本进化问题的异常完整的理解，例如遗传差异如何有助于生物占据不同的生态环境的能力。

A central goal of biology is to understand ecological and genetic factors which have contributed to the diversity of life. Adaptation to different ecological conditions occurs through changes in the genome and in visible traits. Few studies have analyzed the genomic differences underlying divergence. This project aims to answer fundamental questions regarding the adaptive differences between two dramatically different wild populations of Mimulus guttatus (yellow monkeyflower). One population consists of tiny, small flowered annual plants living in extreme alpine conditions. The other population includes large-flowered perennials inhabiting sand dunes in a coastal temperate environment. This study will use genome mapping approaches to identify and characterize the genetic basis of trait differences in a common garden environment. In addition, this experiment will reveal how particular genotypes perform in different natural environments with respect to fitness. By analyzing recombinant inbred lines (advanced generation hybrids between annual and perennial) in a reciprocal transplant experiment, fitness variation associated with specific genomic regions in each of the two natural environments will be assessed. This genetic dissection of local adaptation will help clarify which traits and chromosome regions are associated with performance in the wild.Results of these experiments will provide an unusually complete understanding of basic evolutionary questions, such as how genetic differences contribute to an organisms' ability to occupy diverse ecological environments.