Improved Phylogenomic Taxon Sampling Noticeably Affects Nonbilaterian Relationships

Department of Earth- and Environmental Sciences, Palaeontology and Geobiology & GeoBio-Center, Ludwig-Maximilians-Universität München, Richard-Wagner-Str. 10, 80333 München, Germany.
Molecular Biology and Evolution (Impact Factor: 14.31). 04/2010; 27(9):1983-7. DOI: 10.1093/molbev/msq089
Source: PubMed

ABSTRACT Despite expanding data sets and advances in phylogenomic methods, deep-level metazoan relationships remain highly controversial. Recent phylogenomic analyses depart from classical concepts in recovering ctenophores as the earliest branching metazoan taxon and propose a sister-group relationship between sponges and cnidarians (e.g., Dunn CW, Hejnol A, Matus DQ, et al. (18 co-authors). 2008. Broad phylogenomic sampling improves resolution of the animal tree of life. Nature 452:745-749). Here, we argue that these results are artifacts stemming from insufficient taxon sampling and long-branch attraction (LBA). By increasing taxon sampling from previously unsampled nonbilaterians and using an identical gene set to that reported by Dunn et al., we recover monophyletic Porifera as the sister group to all other Metazoa. This suggests that the basal position of the fast-evolving Ctenophora proposed by Dunn et al. was due to LBA and that broad taxon sampling is of fundamental importance to metazoan phylogenomic analyses. Additionally, saturation in the Dunn et al. character set is comparatively high, possibly contributing to the poor support for some nonbilaterian nodes.

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Available from: Gert Wörheide, Aug 27, 2015
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    • "tationally intensive for some phylogenomic datasets ( e . g . , Nesnidal et al . 2010 , Ryan et al . 2013 ; Moroz et al . 2014 ) . Generally , Bayesian analyses using the CAT model , which has been shown to suppress LBA artifacts ( Latrillot et al . 2007 ) , have recovered sponges as sister to all remaining animals ( Philippe et al . 2009 , 2011 ; Pick et al . 2010 ; Nosenko et al . 2013 , but see Borowiec et al . 2015 ; Whelan et al . 2015 ) . A sister relationship between cnidarians and ctenophores has only been recovered in analyses that used the CAT model on datasets dominated by ribosomal protein genes ( Philippe et al . 2009 ; Nosenko et al . 2013 ) , and Whelan et al . ( 2015 ) showed ribos"
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