The pectoral fin of Tiktaalik roseae and the origin of the tetrapod limb

@article{Shubin2006ThePF,
  title={The pectoral fin of Tiktaalik roseae and the origin of the tetrapod limb},
  author={Neil H. Shubin and Edward B. Daeschler and Farish A. Jenkins},
  journal={Nature},
  year={2006},
  volume={440},
  pages={764-771}
}
Wrists, ankles and digits distinguish tetrapod limbs from fins, but direct evidence on the origin of these features has been unavailable. Here we describe the pectoral appendage of a member of the sister group of tetrapods, Tiktaalik roseae, which is morphologically and functionally transitional between a fin and a limb. The expanded array of distal endochondral bones and synovial joints in the fin of Tiktaalik is similar to the distal limb pattern of basal tetrapods. The fin of Tiktaalik was… 

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