During this project the relative gene order of a sipunculan will be analyzed, the entire sequence of cytochrome oxidase (CO) subunits I - III for this species will be derived, and same will be done for partial CO I - III sequences. These data will permit the creation of a molecular phylogeny of the Sipuncula relative to other closely related eucoelomate protostome phyla for which sequence data are presently available. Separate phylogenies will be derived based on relative gene order and CO I - III sequence data, and those will be checked for congruence as a test of the two methods. Partial sequence data from at least five other sipunculan species will be analyzed with the original sequence data in order to create a phylogeny of the six described families of the phylum. Using this information it will be possible to produce an independent test of a phylogenetic analysis based solely on morphology. %%% The Sipuncula is a widely distributed group that is little known and poorly understood genetically and phylogenetically. Though not a large phylum, this limited diversity hasn't facilitated understanding of either the evolution of the group itself or the relationship of the phylum to metazoan evolution based upon phenotypic (morphological and ontogenetic) characters. The gene order and sequence data that will result from this study will be essential for characterizing fine- and coarse-grained evolution of the mitochondrial genome within the entire group. Such information will reveal answers about phylogeny within the Sipuncula and affinities with the Metazoa, and will also provide baseline genetic information for further studies concerning the biogeography of widespread species and population variation of ocean-dispersed larval organisms. All of the foregoing is important because marine species are under-represented in studies of systematics and biodiversity.
