A Cretaceous terrestrial snake with robust hindlimbs and a sacrum

@article{Apestegua2006ACT,
  title={A Cretaceous terrestrial snake with robust hindlimbs and a sacrum},
  author={Sebasti{\'a}n Apestegu{\'i}a and Hussam Zaher},
  journal={Nature},
  year={2006},
  volume={440},
  pages={1037-1040}
}
It has commonly been thought that snakes underwent progressive loss of their limbs by gradual diminution of their use. However, recent developmental and palaeontological discoveries suggest a more complex scenario of limb reduction, still poorly documented in the fossil record. Here we report a fossil snake with a sacrum supporting a pelvic girdle and robust, functional legs outside the ribcage. The new fossil, from the Upper Cretaceous period of Patagonia, fills an important gap in the… 
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