The braincase and jaws of a Devonian ‘acanthodian’ and modern gnathostome origins

@article{Brazeau2009TheBA,
  title={The braincase and jaws of a Devonian ‘acanthodian’ and modern gnathostome origins},
  author={Martin D. Brazeau},
  journal={Nature},
  year={2009},
  volume={457},
  pages={305-308}
}
Modern gnathostomes (jawed vertebrates) emerged in the early Palaeozoic era, but this event remains unclear owing to a scant early fossil record. The exclusively Palaeozoic ‘acanthodians’ are possibly the earliest gnathostome group and exhibit a mosaic of shark- and bony fish-like characters that has long given them prominence in discussions of early gnathostome evolution. Their relationships with modern gnathostomes have remained mysterious, partly because their un-mineralized endoskeletons… 

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