Why Sequence a Liverwort?
The origin of land plants (embryophytes) was one of the major evolutionary events in the history of planet earth. Experimental, paleontological, morphological, and molecular systematic data all point to the liverworts as being some of the first plants to evolve and colonize the Ordovician landscape. Thus liverworts are a key group to include in any comparative study aimed at understanding the origin and evolution of organisms that now cover much of terrestrial earth. Marchantia polymorpha is a common, easily cultivated liverwort that exhibits many primitive characteristics of both liverworts and land plants. M. polymorpha has been widely studied by researchers in physiology, anatomy, and genetics and is included as the exemplar in most phylogenetic analyses of land plants. The M. polymorpha genome sequence will be useful in several ways. The recent sequencing of Selaginella moellendorffii and Physcomitrella patens genomes has already made genomic comparisons at deeper phylogenetic leve