Collaborative Research: Exploring the Evolution of an Extreme Makeover in Ferns

“铁线蕨”（属于铁线蕨属）是典型的蕨类植物--解剖精美，陆生，喜阴。“鞋带蕨类”（属于一个被称为vittarioids的群体）是非常不同的：高度简化的，居住在树冠上的附生植物，具有重复的基因组，表现出加速的分子进化速度。令人惊讶的是，铁线蕨和带蕨类是密切相关的，包括生命之树的一个分支-一个明显见证了极端形态，生态和基因组改造的谱系。拟议的研究旨在通过分析DNA序列数据，首先建立这些蕨类植物的强大的遗传学。通过对蕨类植物从“马尾毛”到“鞋带”转变过程的分析，可以更好地揭示蕨类植物从“马尾毛”到“鞋带”转变的进化历史，从而更好地阐明蕨类植物形态简化、生态转变、基因组复制和分子进化速率加速等进化过程。由于所有这些过程在生命之树中经常遇到，但人们对其了解甚少，因此在此努力揭示和描述它们之间的联系具有广泛的相关性。该项目包括一个多学科的培训计划，以促进学习，教学和发现，并直接针对本科生和研究生感兴趣的植物系统学，分子进化和遗传学领域。该项目还将追求重要的科学教育和推广目标。

The "maidenhair ferns" (belonging to the genus Adiantum) are quintessential ferns -- beautifully dissected, terrestrial, and shade-loving. The "shoe-string ferns" (belonging to a group known as vittarioids) are extremely different: highly simplified, canopy-dwelling epiphytes, with duplicated genomes that exhibit accelerated rates of molecular evolution. Surprisingly, Adiantum and the vittarioids are closely related, comprising a single branch of the tree of life -- a lineage that evidently witnessed an extreme morphological, ecological, and genomic makeover. The proposed research aims to first establish a robust phylogeny for these ferns through analyses of DNA sequence data. Subsequent analyses can then reveal the evolutionary history of the "maidenhair" to "shoestring" fern transformation.By better characterizing the evolutionary history of this extreme makeover in ferns, this study will better elucidate the evolutionary processes of morphological simplification, ecological transition, genome duplication, and molecular evolutionary rate acceleration. Because all of these processes are frequently encountered across the tree of life, but poorly understood, efforts here to uncover and characterize links among them are broadly relevant. This project encompasses a multidisciplinary training program to promote learning, teaching, and discovery, and is squarely aimed at undergraduate and graduate students interested in the areas of plant systematics, molecular evolution, and phylogenetics. The project will also pursue significant science education and outreach goals.