Phylogeny, classification and character polarity of the Osteostraci (Vertebrata)

@article{Sansom2009PhylogenyCA,
  title={Phylogeny, classification and character polarity of the Osteostraci (Vertebrata)},
  author={Robert S. Sansom},
  journal={Journal of Systematic Palaeontology},
  year={2009},
  volume={7},
  pages={115 - 95}
}
  • Robert S. Sansom
  • Published 1 March 2009
  • Biology
  • Journal of Systematic Palaeontology
Synopsis The jawless Osteostraci are the sister taxon to jawed vertebrates and, thus, are integral to understanding the evolution of gnathostomes from a jawless ancestor. Our understanding of this episode is currently hampered by incomplete knowledge of osteostracan phylogenetics and character polarity. Previous hypotheses of osteostracan intrarelations are reviewed and synthesised into two conflicting hypotheses ‐ ’Tremataspis‐basal’ versus ’Ateleaspis‐basal’ models, both related to the… Expand
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