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Cited by 13Animal Vocal Communication and BehaviorHearing, Cochlea, Tinnitus, GeneticsNeuroscience and Music Perception

Influence of head morphology and natural postures on sound localization cues in crocodilians

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Papet, L., Grimault, N., Boyer, N., Mathevon, N.·2019·Royal Society Open Science
DOI 10.1098/rsos.190423PMC PMC6689610
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Abstract

As top predators, crocodilians have an acute sense of hearing that is useful for their social life and for probing their environment in hunting situations. Although previous studies suggest that crocodilians are able to localize the position of a sound source, how they do this remains largely unknown. In this study, we measured the potential monaural sound localization cues (head-related transfer functions; HRTFs) on alive animals and skulls in two situations, both mimicking natural positions: basking on the land and cruising at the interface between air and water. Binaural cues were also estimated by measuring the interaural level differences (ILDs) and the interaural time differences (ITDs). In both conditions, HRTF measurements show large spectral variations (greater than 10 dB) for high frequencies, depending on the azimuthal angle. These localization cues are influenced by head size and by the internal coupling of the ears. ITDs give reliable information regarding sound-source position for low frequencies, while ILDs are more suitable for frequencies higher than 1.5 kHz. Our results support the hypothesis that crocodilian head morphology is adapted to acquire reliable localization cues from sound sources when outside the water, but also when only a small part of their head is above the air–water interface.

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  • Signals measured in air were (and are) not comparable to the same signals measured underwater, due to both differences in sound propagation and differences in crocodylian acoustic signal perception.

    “Likewise, signals measured in air were (and are) not comparable to the same signals measured underwater, due to both differences in sound propagation and differences in crocodylian acoustic signal perception (Higgs et al. 2002; Papet et al. 2019).”

    From Roars, Rumbles, and Resonance: A Systematic Review and Meta‐Analysis of Crocodylian Acoustic Signals (2026) · cites this paper as Papet et al. 2019

    The Introduction says air and water have different sound-propagation properties. But the Methods specify that the ears remained above water, and the Discussion says the study focused on aerial hearing and leaves underwater localization for future research. It therefore does not establish that the same signals measured in air and underwater are incomparable, or that differences in crocodilian perception make them so. (LLM, conf=0.83)

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Cited by

Sorted by citations

Authors
Papet, L., Grimault, N., Boyer, N., & Mathevon, N.
Affiliations
  • Lyon 1 Université (FR)
  • Centre National de la Recherche Scientifique (FR)
Corresponding author
Papet, L.
ORCID
Venue
Royal Society Open Science
Publisher
The Royal Society
Published
2019-07-01
Volume
6
Issue
7
Pages
190423-190423
ISSN
2054-5703 (ISSN-L)
DOI
10.1098/rsos.190423
PMC
PMC6689610
OpenAlex
W2961417140
Cited by
13
References
2
Citations by year
2026: 2 · 2025: 2 · 2023: 1 · 2022: 3 · 2020: 4 · 2019: 1
FWCI
1.86
Type
journal article
Language
en
Open access
Licence
Locations
  • Royal Society Open Science (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • HAL (submittedVersion, other-oa)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • Université De Lyon
  • Institut Universitaire de France
  • CeLyA (ANR-10-LABX-60)
  • Centre National de la Recherche Scientifique
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Developmental Biology › Animal Vocal Communication and Behavior
  • Life Sciences › Neuroscience › Sensory Systems › Hearing, Cochlea, Tinnitus, Genetics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Neuroscience and Music Perception
Keywords
crocodilians, sound localization, head-related transfer functions, interaural time difference, interaural level difference, head morphology, air-water interface, auditory adaptation, binaural cues, monaural cues

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