Abstract
Many reptiles, and other vertebrates, have internally coupled ears in which a patent anatomical connection allows pressure waves generated by the displacement of one tympanic membrane to propagate (internally) through the head and, ultimately, influence the displacement of the contralateral tympanic membrane. The pattern of tympanic displacement caused by this internal coupling can give rise to novel sensory cues. The auditory mechanics of reptiles exhibit more anatomical variation than in any other vertebrate group. This variation includes structural features such as diverticula and septa, as well as coverings of the tympanic membrane. Many of these anatomical features would likely influence the functional significance of the internal coupling between the tympanic membranes. Several of the anatomical components of the reptilian internally coupled ear are under active motor control, suggesting that in some reptiles the auditory system may be more dynamic than previously recognized.
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Acknowledgments
This work stems from my participation in the 2014 International Symposium on Internally Coupled Ears, and I am indebted to the organizers (C. Carr, J. Christensen-Dalsgaard, and J.L. van Hemmen) for their hospitality and kindness. Much of this essay was drafted while a guest of the Chinese Academy of Sciences; I am indebted to the CAS and Prof. Yehzong Tang for their support.
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This article belongs to a Special Issue on Internally Coupled Ears (ICE).
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Young, B.A. Anatomical influences on internally coupled ears in reptiles. Biol Cybern 110, 255–261 (2016). https://doi.org/10.1007/s00422-016-0699-1
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DOI: https://doi.org/10.1007/s00422-016-0699-1