Project Details
Projekt
A phylogenomic approach to resolve deep phylogenetic incongruences among Phylum Porifera
Subject Area
Evolution, Anthropology
Term
from 2005 to 2012
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 5453222
Deep level metazoan relationships are still far from being resolved. Expanding molecular datasets and continuing advances in phylogenomic methods are increasingly being used, but important nodes among non-bilaterian animals remain difficult to resolve. For example, some recent phylogenomic analyses found ctenophores to be the earliest-branching metazoan taxon and favoured a sister-group relationship between sponges and cnidarians, while other analyses suggest that the Placozoa diverged first or that sponges are a paraphyletic assemblage that share a grade of construction rather than common ancestry. We have now assembled several multi-gene datasets derived from ESTs, with different taxon- and genesampling. A strongly supported monophyletic Porifera with unexpected internal topology is always recovered and most analyses favour a sister-group relationship of Ctenophora+Cnidaria, reviving the "Coelenterata" concept. However, Placozoa relationships remain unstable as they are highly dependent on taxon sampling, evolutionary model selection and outgroup choice. In the last phase of the project we will test these hypotheses by adding additional data of selected taxa and conduct more critical data analyses aiming at a more robust resolution of the branching order of all non-bilaterian metazoan groups.
DFG Programme
Priority Programmes
Subproject of
SPP 1174:
Deep Metazoan Phylogeny
