The evolutionary history of land plants over the last 500 million years is characterized by periodic bursts of diversification following major climatic shifts, specific geologic events, or the evolution of specific characters. Speciation is then so rapid that the relationships among descendants are hard to identify, and large sets of data are needed to resolve the family tree. The moss lineage Hypnanae underwent an explosive radiation following its origin 165 mya. Today, it comprises about 5,000 species, but their grouping into evolutionary units is obscure. Inferences from extensive sets of genes sampled using a gene enrichment strategy combined with gene expression data will provide a robust framework to further our understanding of this diverse, and ecologically important lineage.
This study focuses on untangling the relationships among species that arose from an explosive diversification, on identifying the geologic or climatic shifts that triggered these events, and on understanding the significance of morphological innovations allowing adaptations to diverse habitats. The target group of mosses is more diverse than conifers, dominates some communities, and plays critical ecological roles throughout the world. Resolving the patterns and processes underlying the rise of a diverse lineage offers an opportunity to understand how these organisms may respond to rapid global change.
