The Role of Mating System Divergence in Plant Speciation

交配系统分歧在植物物种形成中的作用

基本信息

批准号：
1754246
负责人：
David Moeller
金额：
$ 97.48万
依托单位：
University of Minnesota-Twin Cities
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-01 至 2024-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1754246&HistoricalAwards=false
关键词：
Role Mating System Divergence Plant

项目摘要

Understanding the formation of new species, the process of speciation, is among the most challenging problems in evolutionary biology. Rates of speciation vary widely among flowering plants and are strongly associated with the degree of reproduction via self-fertilization versus mating with other individuals (known as the plant 'mating system'). This project integrates new evolutionary theory, field and laboratory experiments, and genomic analyses to test key hypotheses about the role of mating system changes in plant speciation. The project investigates the processes that determine where and when strong barriers to mating occur. It will clarify whether evolutionary changes in rates of self-fertilization directly promote reproductive isolation between diverging species. The experimental work focuses on two subspecies of the California annual plant, Clarkia xantiana, which differ in mating system. One subspecies is primarily self-fertilizing the other is primarily outcrossing. These plants are ideal for study because they exhibit features of newly formed species. However, they have only recently diverged and can still interbreed. Moreover, their flowers are substantially different where they co-occur, a signature of the speciation process. The proposed work will also involve extensive outreach to the public via an innovative program called, 'Market Science', where researchers present topics to and engage directly with the public at local farmers' markets. This highly successful program will be expanded to include new topics on evolutionary biology. The proposed project will also directly involve undergraduates in authentic research in the classroom.The proposed work address three primary objectives. Aim 1 examines the role of natural selection in the evolution of reproductive character displacement between sister outcrossing and selfing lineages. This work involves the development of novel theoretical models of character displacement that incorporate divergence in mating system. It also involves large-scale field experiments that quantify the role of individual traits in conferring reproductive isolation and determine their genetic basis. Aim 2 examines the ecological and genetic costs of hybrid formation between sister outcrossing and selfing lineages. This work involves field experiments and genomic analyses that quantify the reproductive fitness of hybrids. Aim 3 synthesizes Aims 1 and 2 by asking about how reproductive isolating mechanisms collectively influence genome-wide patterns of variation and introgression between the two taxa. This integrative work will advance evolutionary research by calling attention to the potential for mating system to influence speciation broadly in nature.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

了解新物种的形成，形成过程，是进化生物学中最具挑战性的问题之一。在开花植物之间的物种速率差异很大，并且与与其他个体（称为植物的“交配系统”）相比，通过自我施用与繁殖程度密切相关。该项目集成了新的进化论，现场和实验室实验，以及基因组分析，以测试有关交配系统变化在植物物种物种中的作用的关键假设。该项目调查了确定何时何地发生交配障碍的过程。它将阐明自我施用率的进化变化是否直接促进分歧物种之间的生殖隔离。实验工作的重点是加利福尼亚州年度工厂克拉克亚·Xantiana的两个亚种，它们在交配系统方面有所不同。一种亚种主要利用另一个亚种主要脱落。这些植物是研究的理想选择，因为它们具有新形成的物种的特征。但是，他们直到最近才分歧，仍然可以杂交。此外，它们的花朵在同时发生的位置有很大不同，这是物种形成过程的标志。拟议的工作还将通过称为“市场科学”的创新计划向公众进行广泛的宣传，研究人员在该计划中展示主题并直接与当地农民市场的公众互动。这个非常成功的计划将扩展到包括有关进化生物学的新主题。拟议的项目还将直接涉及课堂上的真实研究。拟议的工作涉及三个主要目标。 AIM 1检查了自然选择在姐妹脱落和自我自我谱系之间生殖特征位移演变中的作用。这项工作涉及开发特征位移的新理论模型，这些模型在交配系统中融合了差异。它还涉及大规模的现场实验，这些实验量化了单个特征在赋予生殖分离中的作用并确定其遗传基础。 AIM 2检查了姐妹脱落和自我自我谱系之间混合形成的生态和遗传成本。这项工作涉及量化杂种生殖适应性的现场实验和基因组分析。 AIM 3通过询问生殖隔离机制如何共同影响整个基因组变异模式和两个分类单群之间的渗入方式，综合目标1和2。这项综合工作将通过关注交配系统在自然界中广泛影响物种的潜力来推动进化研究。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的影响评估标准通过评估来支持的。