Evolution of the new vertebrate head by co-option of an ancient chordate skeletal tissue

  title={Evolution of the new vertebrate head by co-option of an ancient chordate skeletal tissue},
  author={David Jandzik and Aaron T. Garnett and Tyler A. Square and Maria V. Cattell and Jr-Kai Yu and Daniel M. Medeiros},
A defining feature of vertebrates (craniates) is a pronounced head that is supported and protected by a robust cellular endoskeleton. In the first vertebrates, this skeleton probably consisted of collagenous cellular cartilage, which forms the embryonic skeleton of all vertebrates and the adult skeleton of modern jawless and cartilaginous fish. In the head, most cellular cartilage is derived from a migratory cell population called the neural crest, which arises from the edges of the central… 

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    Journal of experimental zoology. Part B, Molecular and developmental evolution
  • 2011
It is proposed that the common ancestors of chordates possessed a genetic regulatory system that was the prototype of chondrogenesis and osteogenesis in vertebrates, resulting in the emergence of cartilage and mineralized bone.

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  • Biology, Medicine
    Journal of experimental zoology. Part B, Molecular and developmental evolution
  • 2007
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