A uniquely specialized ear in a very early tetrapod

@article{Clack2003AUS,
  title={A uniquely specialized ear in a very early tetrapod},
  author={Jennifer Alice Clack and Per Erik Ahlberg and Sarah M. Finney and Patricio Dom{\'i}nguez Alonso and J. Robinson and Richard A. Ketcham},
  journal={Nature},
  year={2003},
  volume={425},
  pages={65-69}
}
The Late Devonian genus Ichthyostega was for many decades the earliest known tetrapod, and the sole representative of a transitional form between a fish and a land vertebrate. However, despite being known since 1932 (ref. 1) from a large collection of specimens, its morphology remained enigmatic and not what was expected of a very primitive tetrapod. Its apparent specializations led it to be considered as a “blind offshoot” or “sidebranch” off the tetrapod family tree, and recent cladistic… 

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