Genetic Models of Speciation by Reinforcement

摘要：强化的物种形成的遗传模型主要研究者：Mark Kirkpatrick大多数物种保持彼此不同只是因为它们避免了杂交。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适合杂交后代的机会。结果，生殖隔离进化，物种形成。这一假设是有争议的，因为目前尚不清楚，面对杂交带来的遗传渗入，分离是否能够进化。这个项目将发展一个关于如何、何时以及为什么通过强化进行物种形成的全面图景。该方法是建立数学模型来描述交配偏好和其他隔离机制的基因进化。该研究将探讨三个关键因素如何影响这一过程：阻止杂交的机制（如交配偏好、栖息地偏好、开花时间差异等），使杂交不适合的遗传因素，亲本种群的地理位置（如它们是相邻的还是完全重叠的）。结果将对我们在哪里可以通过强化发现物种形成做出定性预测，并提供可以直接根据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的其他各种问题。现代进化生物学对基因如何在种群内进化有了相当全面的了解，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，为调控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.