Meeting Abstract
P2.106 Tuesday, Jan. 5 Integrative approaches for reconstructing the Porifera Tree of Life (PorToL) THACKER, R.W.*; BANGALORE, P.; DIAZ, M.C.; HILL, A.; LAVROV, D.; LOPEZ, J.; PETERSON, K.; POMPONI, S.; REDMOND, N.; COLLINS, A.G.; U. Alabama Birmingham; U. Alabama Birmingham; Museo Margarita; U. Richmond; Iowa State U.; Nova Southeastern U.; Dartmouth U.; Florida Atlantic U.; Smithsonian Institution; Smithsonian Institution thacker@uab.edu
Sponges (phylum Porifera) are among the earliest diverging metazoans, with over 8,000 valid species. Despite their importance in benthic habitats worldwide, phylogenetic relationships within Porifera are not well resolved. In particular, the monophyly of its largest class, Demospongiae, is questioned, as well as the relationships among its major lineages. Our team seeks to establish a robust phylogeny of sponges by integrating traditional morphological systematics with multi-tiered analyses of gene sequences. Tier 1, representing each family of sponges, will assess the monophyly and branching order of major lineages (orders and suborders) by sequencing 11 nuclear genes and complete mitochondrial genomes. Tier 2, representing at least 90% of sponge genera, will examine interfamilial relationships and morphological character evolution by sequencing 8 nuclear and mitochondrial genes. Tier 3, including at least 4,000 species, will assess relationships among species and genera, using traditional morphology and sequences from 2 barcoding genes. At the scale of major lineages, we will present 3 alternative views of sponge evolution based on phylogenies constructed from sequences of (1) nuclear ribosomal 18S subunits, (2) 7 nuclear genes, and (3) whole mitochondrial genomes. To illustrate typical species-level questions, we will present evidence supporting the reclassification of Hyrtios violaceus from family Thorectidae to family Dysideidae. The phylogenies generated by PorToL provide an evolutionary context that will improve the understanding of all aspects of sponge biology.
