Phylogeny and evolutionary history of the amniote egg

  title={Phylogeny and evolutionary history of the amniote egg},
  author={J. Matthias Starck and James R. Stewart and Daniel G. Blackburn},
  journal={Journal of Morphology},
  pages={1080 - 1122}
We review morphological features of the amniote egg and embryos in a comparative phylogenetic framework, including all major clades of extant vertebrates. We discuss 40 characters that are relevant for an analysis of the evolutionary history of the vertebrate egg. Special attention is given to the morphology of the cellular yolk sac, the eggshell, and extraembryonic membranes. Many features that are typically assigned to amniotes, such as a large yolk sac, delayed egg deposition, and… 

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