What is LiToL?
This NSF Assembling the Tree of Life (ATOL) project aims to resolve the liverwort Tree of Life. There is mounting evidence that liverworts (Phylum Marchantiophyta) were the first green plants to diversify on land some 500,000 million years ago and as such they are the oldest living lineage of land plants. This species-rich group of small green plants is remarkably diverse in structure, and includes ancient lineages as well as more recent radiations of closely related species. The antiquity of liverworts and the rich biodiversity at all taxonomic levels provide an unparalleled window into early land plant diversification. This collaborative effort brings together experts from around the world for a multidisciplinary, highly integrated approach that combines anatomical and developmental features with DNA sequence and genome structural characters to resolve phylogenetic relationships across the entire spectrum of liverwort diversity. Three general types of data are being compiled: 1) conservative morphological and genome characters to resolve deep "backbone" relationships, 2) anatomical/developmental data to resolve intermediate-depth lineages, and 3) morphological and DNA sequence characters to resolve relationships among a sample of 800 taxa representing all genera of liverworts. A second major goal of the project is to integrate phylogenetic inferences and bioinformatic efforts between this and other on-going NSF-supported projects, including several funded ATOL programs.