VALLES, Y.; HALANYCH, K.; BOORE, J.; Univ. of Califonia, Berkeley / DOE Joint Genome Institute; Auburn Univ, Alabama; Univ. of Califonia, Berkeley / DOE Joint Genome Institute: Annelids in the Mist: The Influence of a New Marker

Reconstructing character evolution for any group of organisms requires a robust phylogeny. Because of improvements in DNA sequencing technology, it is now possible to compare large datasets of nucleotide and amino acid sequences, as well as �genome level features�, such as the relative order of genes, for reconstructing evolutionary relationships. Annelids are an incredible group of organisms that show great diversity of ecological niches, morphological features, reproductive strategies, etc. Despite the use of several types of data, (18S rDNA, Elongation Factor 1a, and morphological features), evolutionary relationships within Annelida remain controversial. More data and a different approach might be warranted. The comparison of the relative arrangement of the (normally) 37 genes in the mitochondrial genome has been shown to be a powerful phylogenetic tool (Boore & Brown, 1998). This, along with comparing the sequences of the contained nucleotides and inferred amino acids, addresses relationships at various taxonomic levels. We have determined the complete mitochondrial genome sequences of many phylogenetically diverse annelids and compare these for inferences of the evolution of key morphological characters (segmentation, chaetae, etc.) and for reconstructing features of genome evolution