Biological Cybernetics

, Volume 110, Issue 4–5, pp 291–302 | Cite as

Coupled ears in lizards and crocodilians

  • Catherine E. Carr
  • Jakob Christensen-Dalsgaard
  • Hilary Bierman


Lizard ears are coupled across the pharynx, and are very directional. In consequence all auditory responses should be directional, without a requirement for computation of sound source location. Crocodilian ears are connected through sinuses, and thus less tightly coupled. Coupling may improve the processing of low-frequency directional signals, while higher frequency signals appear to be progressively uncoupled. In both lizards and crocodilians, the increased directionality of the coupled ears leads to an effectively larger head and larger physiological range of ITDs. This increased physiological range is reviewed in the light of current theories of sound localization.


Auditory Neural coding Lizard Alligator Barn owl 



We gratefully acknowledge the assistance of J. Matthews with the computation of Fisher information statistics. This research was sponsored by the National Institute on Deafness and Other Communications Disorders (NIDCD) Grant DC-000436 (CEC) and by the Danish Natural Science Research Council (J.C-D)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Department of BiologyUniversity of Maryland College ParkCollege ParkUSA
  2. 2.Department of BiologyUniversity of Southern DenmarkOdenseDenmark

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