Dissertation Research: Evolutionary History of Reproductive Systems in Closely Related Taxa of the Lichen-forming Genus Porpidia (Ascomycota)

论文研究：地衣形成属 Porpidia（子囊菌门）密切相关类群的生殖系统的进化史

• 批准号: 0105024
• 负责人: Gregory Mueller
• 金额: $ 1万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2003-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0105024&HistoricalAwards=false
• 关键词: Dissertation; Research; Evolutionary; History; Reproductive

0105024MuellerThe overall objectives of this research project are to clarify relationships within the genus Porpidia (lichen-forming Ascomycota), and to analyze the distribution and interdependence of transitions between reproductive modes within and among its species. The genus was chosen, due to its accumulation of closely related taxa that show contrasting reproductive modes. The P. flavocoerulescens (sexual)/P. melinodes (asexual) "species pair" was selected for detailed population-level analyses. Hypothetical patterns of changes between the two modes of reproduction will be tested using a phylogenetic approach. The underlying population structure and history within the "species pair" will be studied using an integrated phylogeographic and genealogical analysis.Today the significance of sexual and asexual reproductive modes and their continued coexistence are still unsolved, despite the in-depth theoretical attention the issue has received. This situation is in part due to the scarcity and disparate nature of available empirical data, which do not allow stringent tests of proposed hypotheses. Model systems such as Porpidia that include closely related species with different modes of reproduction ranging from sexual to asexual provide important means to gain insight into the history and consequences of different levels of recombination. So far, investigations have concentrated almost exclusively on either the phylogenetic or population-genetic aspects of the problem. The present study will be the first in lichenized ascomycetes to integrate both phylogenetic and population-genetic approaches. It will not only infer patterns of evolutionary history, but also provide insight into the underlying population processes and historical events shaping these patterns.

0105024Mueller该研究项目的总体目标旨在阐明孢子虫属（地衣形成的comcomycota）内的关系，并分析其物种内部和物种之间生殖模式之间过渡的分布和相互依存关系。由于其积累了密切相关的分类群，因此选择了该属，该分类单元显示出对比鲜明的生殖模式。 P. flavocoerulescens（性）/p。选择了Melinodes（无性）“物种对”进行详细的种群分析。将使用系统发育方法测试两种繁殖模式之间变化的假设模式。 “物种对”中的基本种群结构和历史将使用综合地理学和家谱分析研究。尽管有深入的理论关注，但性行为和无性生殖模式的重要性及其持续共存仍然无法解决。这种情况部分是由于可用经验数据的稀缺性和不同的性质，这不允许对提议的假设进行严格的检验。模型系统（例如孔培氏菌），包括与性别不同的物种，从性行为到无性繁殖，提供了重要的手段，以深入了解不同水平重组的历史和后果。到目前为止，研究几乎完全集中在问题的系统发育或种群遗传方面。本研究将是地衣化的comycetes中的第一个整合系统发育和种群遗传学方法的研究。它不仅会推断进化史的模式，而且还可以深入了解塑造这些模式的基本人口过程和历史事件。