Bone conduction pathways confer directional cues to salamanders

G. Capshaw*, J. Christensen-Dalsgaard, D. Soares, C. E. Carr


Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

4 Downloads (Pure)


Sound and vibration are generated by mechanical disturbances within the environment, and the ability to detect and localize these acoustic cues is generally important for survival, as suggested by the early emergence of inherently directional otolithic ears in vertebrate evolutionary history. However, fossil evidence indicates that the water-adapted ear of early terrestrial tetrapods lacked specialized peripheral structures to transduce sound pressure (e.g. tympana). Therefore, early terrestrial hearing should have required nontympanic (or extratympanic) mechanisms for sound detection and localization. Here, we used atympanate salamanders to investigate the efficacy of extratympanic pathways to support directional hearing in air. We assessed peripheral encoding of directional acoustic information using directionally masked auditory brainstem response recordings. We used laser Doppler vibrometry to measure the velocity of sound pressure-induced head vibrations as a key extratympanic mechanism for aerial sound reception in atympanate species. We found that sound generates head vibrations that vary with the angle of the incident sound. This extratympanic pathway for hearing supports a figure-eight pattern of directional auditory sensitivity to airborne sound in the absence of a pressure-transducing tympanic ear.

TidsskriftJournal of Experimental Biology
Udgave nummer20
StatusUdgivet - okt. 2021

Bibliografisk note

Funding Information:
Funding This work was supported by National Institute on Deafness and Other Communication Disorders (NIDCD/NIH) training grant T32 DC-000046 to the University of Maryland?s Center for Comparative and Evolutionary Biology of Hearing (G.C.), and National Institutes of Health grant DC-000436 (C.E.C.), grants from the Carlsberg Foundation 2009-01-0292, 2012-01-0662 (J.C.-D.), and research grants from The Explorer?s Club Washington Group (G.C.) and the American Society of Ichthyologists and Herpetologists (G.C.). Deposited in PMC for release after 12 months.

Publisher Copyright:
© 2021 Company of Biologists Ltd. All rights reserved.


Dyk ned i forskningsemnerne om 'Bone conduction pathways confer directional cues to salamanders'. Sammen danner de et unikt fingeraftryk.