Polydactyly in the earliest known tetrapod limbs

@article{Coates1990PolydactylyIT,
  title={Polydactyly in the earliest known tetrapod limbs},
  author={Michael I. Coates and Jennifer Alice Clack},
  journal={Nature},
  year={1990},
  volume={347},
  pages={66-69}
}
NEW specimens of the earliest known tetrapod limbs shows them to be polydactylous. The forelimb of Acanthostega has eight digits and the hindlimb of Ichthyostega has seven. Both of these come from the Upper Devonian of East Greenland, complementing the only other known Devonian tetrapod limb, that of Tulerpeton from Russia1, which has six digits. The morphology of the specimens suggests that limbs with digits may have been adaptations to an aquatic rather than a terrestrial environment. The… 

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