A quote from the paper (which by the way, interesting stuff):
quote:
The placement of ctenophores (comb jellies) as the sister group to all other sampled metazoans is strongly supported in all our analyses. This result, which has not been postulated before, should be viewed as provisional until more data are considered from placozoans and additional sponges. If corroborated by further analyses, it would have major implications for early animal evolution, indicating either that sponges have been greatly simplified or that the complex morphology of ctenophores has arisen independently from that of other metazoans. Independent analyses of ribosomal and non-ribosomal proteins (Supplementary Information and Supplementary Fig. 10) indicate that support for this hypothesis (and for others presented for the first time here, such as Clade A and Clade B) is much greater in the combined analyses than in partitioned analyses with fewer genes. This may explain why these novel clades have not been recovered before, because support requires very broad gene sampling
Emphasis mine.
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