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

本研究探讨了维持南加利福尼亚金菖蒲（Mimulus aurantiacus）沿海和内陆种群间空间离散的花色多态性的因素。沿海种群只开红色的花，而离海岸约30公里处则突然过渡到黄色的花。这种模式使得aurantiacus成为一个非常有趣的系统，可以用来研究这种多态性是否受到基因流动的历史障碍的影响，或者是否（以及如何）自然选择形成了它。我们将结合分子遗传学、野外观察和实验研究来检查这些形态之间的形态、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性中的相对作用。这个研究项目对于增加我们对维持自然界性状变化的力量的理解将是重要的。初步结果暗示自然选择在保持这种多态性中起着重要作用，但选择力仍不清楚。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。他们参与这些研究对其成功至关重要，并提供了增强的教育经验。

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.