Rapid braincase evolution between Panderichthys and the earliest tetrapods

@article{Ahlberg1996RapidBE,
  title={Rapid braincase evolution between Panderichthys and the earliest tetrapods},
  author={Per Erik Ahlberg and Jennifer Alice Clack and Ervīns Lukevi{\vc}s},
  journal={Nature},
  year={1996},
  volume={381},
  pages={61-64}
}
THE panderichthyids (or elpistostegids) are the most tetrapod-like fishes that still retain paired fins rather than limbs. During the transition from fish to tetrapod, the braincase, previously subdivided by a joint, was remodelled into a solid structure4. Here we present the complete braincase of the fish Panderichthys rhombolepis, a Middle Devonian1 member of the tetrapod stemgroup2,3. Panderichthys has an externally tetrapod-like skull2, but we show that the braincase retained the… 

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The skull, exceptionally preserved braincase, shoulder girdle and partial pelvis of Ventastega curonica are presented, a transitional intermediate form between the ‘elpistostegids’ Panderichthys and Tiktaalik and the Devonian tetrapods (limbed vertebrates) Acanthostega and Ichthyostega.
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