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PubMed · 1069313

Ear and hearing in Sphenodon punctatus.

C Gans·E G Wever
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Abstract

Observations on Sphenodon punctatus have revealed new features of the anatomy of the ear,and measurements in a living specimen by means of cochlear potentials show the form and level of this ear's performance in sound reception. For an animal lacking an external ear opening and a functional tympanic membrane, the sensitivity of from 100-900 Hz is surprisingly good in low tones with peak response around 200-400 Hz. The inner ear is well developed, with a tectorial membrane connected to a tectorial plate that extends throughout the cochlea. The best region of sensitivity agrees well with the main frequency components of the animal's vocalizations.

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Action PotentialsAnimalsBiological EvolutionBone ConductionCochleaEarHearingReptilesJournal Article

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C Gans, E G Wever. 1976. Ear and hearing in Sphenodon punctatus.. https://doi.org/10.1073/pnas.73.11.4244

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