Discovery of the earliest-known tetrapod stapes

@article{Clack1989DiscoveryOT,
  title={Discovery of the earliest-known tetrapod stapes},
  author={Jennifer Alice Clack},
  journal={Nature},
  year={1989},
  volume={342},
  pages={425-427}
}
  • J. Clack
  • Published 1 November 1989
  • Medicine
  • Nature
THE evolution of the middle ear is central to the discussion of how the first tetrapods adapted to life on land as well as their phylogeny1–3. Here I report the discovery of the stapes of Acanthostega gunnari, from the Upper Devonian of east Greenland. This is the earliest tetrapod stapes so far described, and it throws new light on both these aspects of early tetrapod biology. It has been assumed that the common inheritance of all early tetrapods was a light, rod-like stapes associated with a… 

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

Patterns and processes in the early evolution of the tetrapod ear.

  • J. Clack
  • Geography
    Journal of neurobiology
  • 2002
TLDR
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Tetrapod-like middle ear architecture in a Devonian fish

TLDR
It is shown that the spiracular region is radically transformed from osteolepiforms and represents the earliest stages in the origin of the tetrapod middle ear architecture, suggesting that the middle ear of early tetrapods evolved initially as part of a spiracular breathing apparatus.

Fish-like gills and breathing in the earliest known tetrapod

TLDR
The discovery of a fish-like branchial skeleton in Acanthostega gunnari, from the Upper Devonian of East Greenland, one of the earliest tetrapods known, provides information on the sequence of acquisition of tetrapod characters, and supports previous suggestions that such characters as legs with digits evolved first for use in water.

Homologies in the fossil record: The middle ear as a test case

TLDR
Examining the middle ear of fossil living animals in terms of the homologies which have been drawn between its parts in different vertebrate groups finds that most of the conceptions have been overturned in recent years by new fossil discoveries and new ways of looking at old data.

The Evolution of Single- and Multiple-Ossicle Ears in Fishes and Tetrapods

TLDR
The Ostariophysi are the hearing specialists of the ray-finned world and include the gonorynchiforms and a much larger group called the Otophysi, distinguished by having some of the anterior neural arches and supraneurals modified into the Weberian apparatus.

The Water-to-Land Transition: Evolution of the Tetrapod Basilar Papilla, Middle Ear, and Auditory Nuclei

TLDR
The water-to-land transition apparently coincided with the coevolution of a tympanic middle ear, a basilar papilla, and a periotic labyrinth in the inner ear, as well as neural pathways devoted to the processing of airborn sound in tetrapods.

The ear region of Latimeria chalumnae: functional and evolutionary implications.

TLDR
The possibility is considered that the canalis communicans does not possess any auditory function but rather is involved in sensing pressure changes during movements involving the intracranial joint, and earlier hypotheses of a putative tympanic ear are refuted.

The neurocranium of Acanthostega gunnari Jarvik and the evolution of the otic region in tetrapods

Abstract The neurocranium of Acanthostega gunnari is described from several specimens, and is the first full description of a Devonian tetrapod braincase. It is shown to resemble the osteolepiform

fossil The neurocranium of Acanthostega gunnari Jarvik and the evolution of the otic region in tetrapods

The neurocranium of Acanthoskga gunnari is described from several specimens, and is the first full description of a Devonian tetrapod braincase. It is shown to resemble the osteolepiform
...

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