Evolution of the Turtle Body Plan by the Folding and Creation of New Muscle Connections

@article{Nagashima2009EvolutionOT,
  title={Evolution of the Turtle Body Plan by the Folding and Creation of New Muscle Connections},
  author={Hiroshi Nagashima and Fumiaki Sugahara and Masaki Takechi and Rolf Ericsson and Yoshie Kawashima-Ohya and Yuichi Narita and Shigeru Kuratani},
  journal={Science},
  year={2009},
  volume={325},
  pages={193 - 196}
}
Shelling Turtles In almost all vertebrates, the shoulder girdle (scapula) lies outside the ribs. The turtle is unique in that the carapace, the dorsal part of the shell, which is formed from the ribs, encapsulates the scapula. To understand the origin of the turtle-specific body plan, Nagashima et al. (p. 193; see the cover; see the Perspective by Rieppel) compared chicken, mouse, and the Chinese soft shelled-turtle, Pelodiscus sinensis. Modern embryos were studied via whole-mount… 

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...

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