DISSERTATION RESEARCH: Divergent selection and the evolution of reproductive isolation across the genus Cakile (Brassicaceae)

物种的定义是它们无法与其他物种成功繁殖。达尔文最初认为，新物种的出现是不同种群适应不同环境的结果。尽管人们普遍承认自然选择在新物种的形成中发挥了作用，但适应不同或相似环境是否加速了生殖隔离的进化，这一问题仍然存在争议。本研究通过描述生殖隔离与Cakile属（一种沿海沙丘植物，跨越了北美东部、加勒比海和地中海的一系列环境变化和地理隔离）的适应性差异的程度，解决了物种形成中的分化适应作用。除了解决长期存在的关于环境和当地适应在物种形成中的作用的问题外，这项研究还与保护倡议有关，因为Cakile是受威胁的沿海栖息地的特有物种。该项目将与墨西哥湾沿岸和加勒比地区的地方和国家保护组织分享信息。该项目也有一个国际组成部分。本科生将接受实验设计和分析方面的训练。每个学生将有机会独立开发项目的一个组成部分。此外，将在夏季招募少数民族高中学生参与研究。

Species are defined by their inability to reproduce successfully with other species. Darwin originally argued that new species arose as a consequence of distinct populations adapting to different environments. Despite the widespread acknowledgment that natural selection plays a role in the formation of new species, the question of whether adaptation to different versus similar environments accelerates the evolution of reproductive isolation remains controversial. This study addresses the role of divergent adaptation in speciation by characterizing the degree to which reproductive isolation correlates with adaptive divergence across the genus Cakile, a coastal dune plant that spans a range of environmental variation and geographical isolation throughout Eastern North America, the Caribbean, and the Mediterranean. In addition to addressing long-standing questions concerning the role of the environment and local adaptation in speciation, this research is relevant to conservation initiatives, since Cakile is endemic to the threatened coastal habitat. The project will share information with local and national conservation groups in the Gulf Coast and Caribbean region. The project also has an international component. Undergraduate students will acquire training in experimental design and analysis. Each student will be given the opportunity to develop a component of the project independently. In addition, minority high school students will be recruited to participate in the research during the summers.