Fish-like gills and breathing in the earliest known tetrapod

@article{Coates1991FishlikeGA,
  title={Fish-like gills and breathing in the earliest known tetrapod},
  author={Michael I. Coates and Jennifer Alice Clack},
  journal={Nature},
  year={1991},
  volume={352},
  pages={234-236}
}
THE origin of tetrapods is generally associated with the emergence of terrestrial vertebrate life. Anatomical features unique to tetrapods are usually considered to be adaptations to the terrestrial environment. Here we report the discovery of a fish-like branchial skeleton in Acanthostega gunnari, from the Upper Devonian of East Greenland, one of the earliest tetrapods known. It shows a proximally expanded ceratohyal and large, ventrally grooved ceratobranchials. Such grooves are found in the… 

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The cranial endoskeleton of Tiktaalik roseae

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Earliest known tetrapod braincase and the evolution of the stapes and fenestra ovalis

ACANTHOSTEGA gunnari, from the Upper Devonian (Famennian) of East Greenland, is the most primitive known tetrapod, and retains many fish-like characters1–4. I report here the discovery of further
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