Development of teeth and jaws in the earliest jawed vertebrates

@article{Rcklin2012DevelopmentOT,
  title={Development of teeth and jaws in the earliest jawed vertebrates},
  author={Martin R{\"u}cklin and Philip C. J. Donoghue and Zerina Johanson and Kate Trinajstic and Federica Marone and Marco Stampanoni},
  journal={Nature},
  year={2012},
  volume={491},
  pages={748-751}
}
Teeth and jaws constitute a model of the evolutionary developmental biology concept of modularity and they have been considered the key innovations underpinning a classic example of adaptive radiation. However, their evolutionary origins are much debated. Placoderms comprise an extinct sister clade or grade to the clade containing chondrichthyans and osteichthyans, and although they clearly possess jaws, previous studies have suggested that they lack teeth, that they possess convergently… 

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