Morphogenesis of the turtle shell: the development of a novel structure in tetrapod evolution

@article{Gilbert2001MorphogenesisOT,
  title={Morphogenesis of the turtle shell: the development of a novel structure in tetrapod evolution},
  author={Scott F. Gilbert and Grace A. Loredo and Alla Brukman and Ann C. Burke},
  journal={Evolution \& Development},
  year={2001},
  volume={3}
}
SUMMARY The turtle shell is an evolutionary novelty that is synapomorphic for chelonians. The carapace is initiated by the entrapment of the ribs by the carapacial ridge (CR), a lateral bulge of the dorsal ectoderm and dermal mesoderm. The mechanisms by which the CR is initiated, the ribs entrapped and the dorsal dermis ossified, remains unknown. Similarly, the formation of the plastron remains unexplained. Here, we present a series of anatomical investigations into plastron and carapace… 

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Emerging from the rib: resolving the turtle controversies.

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