The phylogenetic position of the comb jellies (Ctenophora) and the importance of taxonomic sampling

@article{Wallberg2004ThePP,
  title={The phylogenetic position of the comb jellies (Ctenophora) and the importance of taxonomic sampling},
  author={Andreas Wallberg and Mikael Thollesson and James S Farris and Ulf Jondelius},
  journal={Cladistics},
  year={2004},
  volume={20}
}
The transition to a vermiform body shape is one of the most important events in animal evolution, having led to the impressive radiation of Bilateria. However, the sister group of Bilateria has remained obscure. Cladistic analyses of morphology indicate that Ctenophora is the sister group of Bilateria. Previous analyses of SSU rRNA sequences have yielded conflicting results; in many studies Ctenophora forms the sister group of Cnidaria + Bilateria, but in others the ctenophores group with… 

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