Developmental basis of limblessness and axial patterning in snakes

@article{Cohn1999DevelopmentalBO,
  title={Developmental basis of limblessness and axial patterning in snakes},
  author={Martin J. Cohn and Cheryll Tickle},
  journal={Nature},
  year={1999},
  volume={399},
  pages={474-479}
}
The evolution of snakes involved major changes in vertebrate body plan organization, but the developmental basis of those changes is unknown. The python axial skeleton consists of hundreds of similar vertebrae, forelimbs are absent and hindlimbs are severely reduced. Combined limb loss and trunk elongation is found in many vertebrate taxa, suggesting that these changes may be linked by a common developmental mechanism. Here we show that Hox gene expression domains are expanded along the body… 
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