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.
