Convergence in the Feeding Apparatuses of Lophophorates and Pterobranch Hemichordates Revealed by 18S rDNA: An Interpretation.

  title={Convergence in the Feeding Apparatuses of Lophophorates and Pterobranch Hemichordates Revealed by 18S rDNA: An Interpretation.},
  author={Kenneth M. Halanych},
  journal={The Biological bulletin},
  volume={190 1},
  • K. Halanych
  • Published 1 February 1996
  • Biology
  • The Biological bulletin
Homology of the feeding apparatus of pterobranch hemichordates and the lophophore of bryozoans, brachiopods, and phoronids has been postulated but never rigorously tested. I employ Patterson's (1, 2) three criteria of conjunction, similarity, and congruence to test this putative homology. Although the conjunction and similarity criteria are satisfied, congruence is not. The congruence test is based on a phylogeny derived from 18s rDNA sequence data which show that pterobranchs and lophophorates… 

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