Dissertation Research: Investigating Phylogeny, Reticulate Evolution, and Gene Tree Discordance in New World Dryopteris (Dryopteridaceae)

蕨类植物是地球上维管植物的第二大类群，是多样性和经济上重要的种子植物的姐妹类群。这个项目将是第一个为广泛分布的蕨类植物绘制家谱的项目，并将利用这棵树来研究一些关键问题，这些问题是关于这一重要但研究不足的植物群是如何进化的。目前的研究将使用DNA序列数据来测试关于物种关系、生物地理学、杂交和基因组加倍（多倍体）在塑造北美木蕨物种（Dryopteris）历史中的作用的几个假设。毛蕨属是一个物种丰富、形态多样、生物地理分布广泛、美丽的属，北美成员长期以来被认为反映了网状（无分支）物种形成的复杂历史。该项目将促进国际合作，并将培养一名女博士生以及她将指导的本科生。所有数据和结果将广泛传播，通过在线数据库、出版物和演讲向科学界传播，通过外联演讲向公众传播，通过蕨类植物博客传播，通过美国植物学会的植物科学计划传播给中学生和高中生。

Ferns are the second largest group of vascular plants on earth, and are the sister group of the diverse and economically important seed plants. This project will be one of the first to produce a family tree for a widespread fern genus, and will employ that tree to investigate a number of critical questions about how evolution has proceeded in this important but understudied group of plants. The current study will use DNA sequence data to test several hypotheses regarding species relationships, biogeography, and the roles of hybridization and genome doubling (polyploidy) in shaping the history of the North American species of woodferns (Dryopteris). Dryopteris is a species-rich, morphologically diverse, biogeographically widespread, and beautiful genus, and the North American members have long been thought to reflect a complex history of reticulate (non-branching) speciation.This project will facilitate international collaboration and will result in the training of a female PhD student as well as undergraduate students that she will mentor. All data and results will be disseminated widely, to the scientific community via online databases, in publications and talks, to the public via outreach presentations, via a fern weblog, and to middle and high school students through the Botanical Society of America's PlantingScience program.