Collaborative Research: The Evolution of Pheromone Signals and Their Role in Behavioral Isolation

合作研究：信息素信号的进化及其在行为隔离中的作用PI：Lynne D.Houck&Amp；Stevan Arnold和Richard C.Feldhoff&Amp；Pamela Feldhoff数百万年来，雄性陆栖火蜥蜴一直在进行一种奇怪的求偶行为，给雌性火蜥蜴注射信息素。这些求偶信息素是蛋白质信号，可以增强雌性的性接受能力。长期以来，生殖交流的例子一直被认为是由男性信号上的性选择(通过女性配偶选择)塑造的。然而，最近的证据表明，求偶信息素是雌性使用的信号--不是用来选择配偶--而是用来识别物种。因此，这种信号系统的进化可能受到配偶识别和行为隔离的指导。我们将使用一个成熟的研究系统来研究雄性求偶信息素信号是否影响行为隔离，从而影响物种形成。我们解决了两个具体的问题：(1)雄性求偶信息素信号是否促进行为隔离？(2)什么过程最好地解释了观察到的行为隔离的进化？在拟议的工作中，我们将重点关注显示不同水平的行为隔离的六个种群对。我们将通过实验操作化学信号来验证男性化学信号有助于行为隔离的假设。其次，我们将使用数学模型来模拟雄性信息素信号和雌性交配偏好在一组相关物种中的联合进化。我们将比较每个模型的模拟数据与行为隔离的实际测量，以确定哪个模型提供了最好的匹配。我们的模拟方法将普遍适用于任何存在已知亲缘关系的物种的通信系统，以及这些物种对之间的行为隔离调查。结合起来，我们的研究将构成行为隔离机制及其演变的一个令人信服的案例研究。

Collaborative Research: The Evolution of Pheromone Signals and their Role in Behavioral IsolationPI: Lynne D. Houck & Stevan Arnold and Richard C. Feldhoff & Pamela Feldhoff For millions of years, male terrestrial salamanders have executed a bizarre courtship that involves injecting females with pheromones. These courtship pheromones are protein signals that enhance the sexual receptivity of females. This example of reproductive communication has long been viewed as being shaped by sexual selection (via female mate choice) on the male signal. More recent evidence, however, implicates courtship pheromones as signals used by the female -not for mate choice- but for species identification. Thus, the evolution of this signaling system may be guided by mate recognition and behavioral isolation. We will use a well-developed study system to investigate whether male courtship pheromone signals affect behavioral isolation and hence speciation. We address two specific questions: (1) Do male courtship pheromone signals promote behavioral isolation? (2) What processes best explain the observed evolution of behavioral isolation? In the proposed work, we will focus on six population pairs showing different levels of behavioral isolation. We will experimentally manipulate chemical signals to test the hypothesis that male chemical signaling contributes to behavioral isolation. Secondly, we will use mathematical models to simulate the joint evolution of the male pheromone signal and female mating preferences across a group of related species. We will compare simulated data from each model with actual measures of behavioral isolation to determine which model gives the best fit. Our simulation methods will apply generally to any communication systems for which there are species of known relatedness and a survey of behavioral isolation between pairs of these species. In combination, our research will constitute a compelling case study of behavioral isolating mechanisms and how they evolve.