Acanthodes and shark-like conditions in the last common ancestor of modern gnathostomes

@article{Davis2012AcanthodesAS,
  title={Acanthodes and shark-like conditions in the last common ancestor of modern gnathostomes},
  author={Samuel P. Davis and John A. Finarelli and Michael I. Coates},
  journal={Nature},
  year={2012},
  volume={486},
  pages={247-250}
}
Acanthodians, an exclusively Palaeozoic group of fish, are central to a renewed debate on the origin of modern gnathostomes: jawed vertebrates comprising Chondrichthyes (sharks, rays and ratfish) and Osteichthyes (bony fishes and tetrapods). Acanthodian internal anatomy is primarily understood from Acanthodes bronni because it remains the only example preserved in substantial detail, central to which is an ostensibly osteichthyan braincase. For this reason, Acanthodes has become an… 

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