DISSERTATION RESEARCH: The Role of Chemical Signaling in the Evolution of Reproductive Isolation in Terrestrial Salamanders

化学信号在陆地蝾螈生殖隔离进化中的作用陆地蝾螈通过称为信息素的化学气味进行交流。某些信息素只在求偶期间使用。这些求偶信息素是由雄性产生的，在求偶期间传递给雌性。这些雄性求偶信息素的典型作用是增加雌性的接受性，这表明求偶的完成速度更快。这些信息素也可能被雌性用来识别不正确的交配对象（来自其他物种的雄性），从而阻止物种之间的杂交。雄性求偶信息素是由蛋白质组成的。有一种蛋白质可以单独发挥作用，大大提高女性的接受能力。这种蛋白质的基因被鉴定出来，并在一系列近亲陆生蝾螈物种中被发现表达。在这种情况下，物种的祖先是已知的，这为研究从基因到蛋白质再到行为的变化的进化提供了机会。本研究将着重于求偶信息素的遗传和生化变异。这些信息将与现有的关于雌性对其同类和不同物种的雄性求爱的行为反应的数据进行比较。这项研究的结果将为研究雌性对雄性化学信号的反应进化提供一个新的视角。

THE ROLE OF CHEMICAL SIGNALING IN THE EVOLUTION OF REPRODUCTIVE ISOLATION IN TERRESTRIAL SALAMANDERSLynne D. Houck and Catherine A. Palmer Terrestrial salamanders communicate by using chemical odors, termed pheromones. Certain pheromones are used only during courtship. These courtship pheromones are produced by the male and delivered to the female during courtship. These male courtship pheromones typically function to increase female receptivity, as indicated by a more rapid completion of the courtship. These same pheromones may also be used by the female to identify incorrect mating partners (males from other species), and hence prevent hybridization between species. The male courtship pheromones are comprised of proteins. One protein in particular can act alone to substantially increase female receptivity. The gene for that protein was identified, and was found to be expressed in a series of closely-related terrestrial salamander species. This setting, for which the ancestry of the species is known, offers an opportunity to investigate the evolution of changes that occur from gene to protein to behavior. This study will focus on genetic and biochemical variation in courtship pheromones. This information will be compared with existing data on female behavioral response to courtships with males of her own and of different species. The results of this investigation will provide a novel perspective on the evolution of female response to a male chemical signal.