DISSERTATION RESEARCH: Maintenance of a Flower Color Polymorphism in Mimulus Aurantiacus

这项研究调查了南加州沿海和内陆种群之间维持空间离散花色多态的因素。海岸种群只开红色的花，而在离海岸大约30公里的地方，突然过渡到黄色的花。这种模式使橙色微藻成为一个非常有趣的系统，用于研究这种多态是否受到历史上基因流动障碍的影响，或者自然选择是否(以及如何)塑造了这种多态。我们将结合分子遗传学、田间观察和实验研究来检验这些变型之间的形态、地理和遗传分化程度，同时试图描述传粉者和非传粉者选择在维持这种多态方面的相对作用。这项研究计划对于增加我们对维持自然界中性状变异的力量的理解将是重要的。初步结果表明，自然选择在保护这种多态方面发挥了很大作用，但选择的力量仍然不清楚。拟议的实地和实验室工作将包括许多本科生研究人员的协助。他们参与这些研究是其成功的关键，并提供了更好的教育体验。

This study investigates the factors maintaining a spatially discrete flower color polymorphism between coastal and inland populations of southern California Mimulus aurantiacus. Coastal populations contain exclusively red flowers, while approximately 30 km from the coast there is an abrupt transition to yellow flowers. This pattern makes M. aurantiacus an extremely interesting system for investigating whether this polymorphism has been influenced by historical barriers to gene flow or whether (and how) natural selection has shaped it. We will use a combination of molecular genetics, field observations, and experimental studies to examine the degree of morphological, geographical, and genetic differentiation between these morphs while attempting to describe the relative roles of pollinator versus non-pollinator selection on the maintenance of this polymorphism. This research program will be important for increasing our understanding of the forces maintaining trait variation in nature. Preliminary results implicate a strong role for natural selection in preserving this polymorphism, but the selective forces remain unclear. Proposed field and laboratory work will include the assistance of many undergraduate researchers. Their involvement in these studies is crucial to its success and provides for enhanced educational experiences.