Genetic Models of Speciation by Reinforcement

摘要：物种形成的遗传模型首席研究员：马克柯克帕特里克大多数物种保持彼此不同，只是因为他们避免杂交。 这种生殖隔离进化的一个主要理论是“强化”假说，该假说认为交配偏好的进化是为了减少产生不合适的杂交后代的机会。 因此，生殖隔离的演变和物种形成的发生。 这一假说是有争议的，因为尚不清楚隔离是否可以在面对伴随杂交的遗传渐渗时进化。这个项目将开发一个全面的图片，如何，何时，以及为什么物种形成的强化可以操作。 该方法是开发数学模型，描述交配偏好和其他隔离机制的基因进化。 该研究将调查三个关键因素如何影响这一过程：防止杂交的机制（例如交配偏好，栖息地偏好，开花时间差异等），使杂交种不太适合的遗传因素，以及亲本种群的地理位置（例如，它们是连续的还是完全重叠的）。 研究结果将对我们在哪里可以通过强化找到物种形成做出定性预测，并提供可以直接针对自然种群数据进行测试的定量预测。 新的数学方法将被开发出来，有望用于进化遗传学中的各种其他问题。现代进化生物学对基因如何在种群内进化有相当全面的理解，但对一个种群如何分裂成两个种群的理解相对较差。 这项研究将阐明物种形成的机制，为调节地球生物多样性的基本过程提供见解。

Abstract: Genetic models of speciation by reinforcementPrincipal investigator: Mark Kirkpatrick Most species remain distinct from one another simply because they avoid interbreeding. A major theory for the evolution of this reproductive isolation is the "reinforcement" hypothesis, which holds that mating preferences evolve to decrease the chance of producing unfit hybrid offspring. As a result, reproductive isolation evolves and speciation occurs. This hypothesis is controversial because it is unclear whether isolation can evolve in the face of the genetic introgression that accompanies hybridization. This project will develop a comprehensive picture of how, when, and why speciation by reinforcement can operate. The approach is to develop mathematical models that describe the evolution of genes for mating preferences and other isolating mechanisms. The research will investigate how three key factors influence the process: the mechanism that prevents interbreeding (e.g. mating preferences, habitat preferences, flowering time differences, etc.), the genetic factors that make hybrids less fit, and the geography of parental populations (e.g. whether they are contiguous or completely overlapping). Results will make qualitative predictions about where we can expect to find speciation by reinforcement, and offer quantitative predictions that can be tested directly against data from natural populations. Novel mathematical methods will be developed that hold promise for use in a wide variety of other problems in evolutionary genetics. Modern evolutionary biology has a quite comprehensive understanding of how genes evolve within populations, but a relatively poor understanding of how one population splits into two. This research will illuminate the mechanisms of speciation, providing insights into the fundamental processes that regulate biodiversity on earth.