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Zhai S, Bornitz M, Eßinger TM, Chen Z, Neudert M. Influence of inner ear impedance on middle ear sound transfer functions. Heliyon 2024; 10:e27758. [PMID: 38524600 PMCID: PMC10958710 DOI: 10.1016/j.heliyon.2024.e27758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 12/15/2023] [Accepted: 03/06/2024] [Indexed: 03/26/2024] Open
Abstract
Introduction For experimental studies on sound transfer in the middle ear, it may be advantageous to perform the measurements without the inner ear. In this case, it is important to know the influence of inner ear impedance on the middle ear transfer function (METF). Previous studies provide contradictory results in this regard. With the current study, we investigate the influence of inner ear impedance in more detail and find possible reasons for deviations in the previous studies. Methods 11 fresh frozen temporal bones were prepared in our study. The factors related to inner ear impedance, including round window membrane stiffness, cochleostomy, cochlea fluid and cochlea destruction were involved in the experimental design. After measuring in the intact specimen as a reference (step 1), the round window membrane was punctured (step 2), then completely removed (step 3). The cochleostomy was performed (step 4) before the cochlear fluid was carefully suctioned through scala tympani (step 5) and scala vestibuli (step 6). Finally, cochlea was destroyed by drilling (step 7). Translational and rotational movement of the stapes footplate were measured and calculated at each step. The results of the steps were compared to quantify the effect of inner ear impedance changing related to the process of cochlear drainage. Results As the inner ear impedance decreases from step 1 to 7, the amplitudes of the METF curves at each frequency gradually increase in general. From step 6 on, the measured METF are significantly different with respect to the intact group at high frequencies above 3 kHz. The differences are frequency dependent. However, the significant decrement of rotational motion appears at the frequencies above 4.5 kHz from the step 5. Conclusion This study confirms the influence of inner ear impedance on METF only at higher frequencies (≥3 kHz). The rotational motions are more sensitive to the drainage of fluid at the higher frequency. Study results that found no influence of cochlea impedance may be due to incomplete drainage of the cochlea.
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Affiliation(s)
- Sijia Zhai
- Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Otorhinolaryngology Head and Neck Surgery, Ear Research Center Dresden (ERCD), Fetscherstraße 74, 01307, Dresden, Germany
| | - Matthias Bornitz
- Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Otorhinolaryngology Head and Neck Surgery, Ear Research Center Dresden (ERCD), Fetscherstraße 74, 01307, Dresden, Germany
| | - Till Moritz Eßinger
- Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Otorhinolaryngology Head and Neck Surgery, Ear Research Center Dresden (ERCD), Fetscherstraße 74, 01307, Dresden, Germany
| | - Zhaoyu Chen
- Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Otorhinolaryngology Head and Neck Surgery, Ear Research Center Dresden (ERCD), Fetscherstraße 74, 01307, Dresden, Germany
| | - Marcus Neudert
- Technische Universität Dresden, Faculty of Medicine Carl Gustav Carus, Department of Otorhinolaryngology Head and Neck Surgery, Ear Research Center Dresden (ERCD), Fetscherstraße 74, 01307, Dresden, Germany
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Ordiway G, McDonnell M, Sanchez JT. Revisiting the Chicken Auditory Brainstem Response: Frequency Specificity, Threshold Sensitivity, and Cross Species Comparison. Neurosci Insights 2024; 19:26331055241228308. [PMID: 38304551 PMCID: PMC10832403 DOI: 10.1177/26331055241228308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 01/09/2024] [Indexed: 02/03/2024] Open
Abstract
The auditory brainstem response (ABR) is important for both clinical and basic auditory research. It is a non-invasive measure of hearing function with millisecond-level precision. The ABR can not only measure the synchrony, speed, and efficacy of auditory physiology but also detect different modalities of hearing pathology and hearing loss. ABRs are easily acquired in vertebrate animal models like reptiles, birds, and mammals, and complement existing molecular, developmental, and systems-level research. One such model system is the chicken; an excellent animal for studying auditory development, structure, and function. However, the ABR for chickens was last reported nearly 4 decades ago. The current study examines how decades of ABR characterization in other animal species support findings from the chicken ABR. We replicated and expanded on previous research using 43 chicken hatchlings 1- and 2-day post-hatch. We report that click-evoked chicken ABRs presented with a peak waveform morphology, amplitude, and latency like previous avian studies. Tone-evoked ABRs were found for frequencies from 250 to 4000 Hertz (Hz) and exhibited a range of best sensitivity between 750 and 2000 Hz. Objective click-evoked and tone-evoked ABR thresholds were comparable to subjective thresholds. With these revisited measurements, the chicken ABR still proves to be an excellent example of precocious avian development that complements decades of molecular, neuronal, and systems-level research in the same model organism.
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Affiliation(s)
- George Ordiway
- Roxelyn and Richard Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
- Central Auditory Physiology Laboratory, Northwestern University, Evanston, IL, USA
| | - Miranda McDonnell
- Roxelyn and Richard Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
- Central Auditory Physiology Laboratory, Northwestern University, Evanston, IL, USA
| | - Jason Tait Sanchez
- Roxelyn and Richard Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
- Central Auditory Physiology Laboratory, Northwestern University, Evanston, IL, USA
- Knowles Hearing Research Center, Northwestern University, Evanston, IL, USA
- Department of Neurobiology, Northwestern University, Evanston, IL, USA
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Fritzsch B, Elliott KL. Fish hearing revealed: Do we understand hearing in critical fishes and marine tetrapods. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 154:3019-3026. [PMID: 37955566 PMCID: PMC10769566 DOI: 10.1121/10.0022355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 09/26/2023] [Accepted: 09/27/2023] [Indexed: 11/14/2023]
Abstract
Hearing evolved in lampreys with a frequency range of 50-200 Hz. This hearing range is comparable to that of elasmobranchs, most non-teleosts, and lungfish. Elasmobranchs most likely use the saccule and the papilla neglecta (PN) for hearing. In non-teleosts and teleosts, lungfish, and certain tetrapods the saccule is the likely sensor for sound reception while the lagena and the PN are important for gravistatic sensing. Coelacanth and most tetrapods have a basilar papilla (BP) for hearing. In coelacanth and tetrapods, the hair cells of the BP are in contact with a basilar and a tectorial membrane. These membranes transmit mechanical vibrations. A cochlear aqueduct (CA) provides a connection between the cerebrospinal fluid that has a sodium rich space in coelacanth and tetrapods while the potassium rich endolymph is known in vertebrates. A unique feature is known in basic sarcopterygians, the intracranial joint, that never developed in actinopterygians and has been lost in lungfish and tetrapods. The BP in coelacanths is thought to generate pressure with the intracranial joint that will be transmitted to the CA. Lungs or a swim bladder are not forming in Chondrichthyes, structures that have a major impact on hearing in teleosts and tetrapods.
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Affiliation(s)
- Bernd Fritzsch
- Department of Biology & Department of Otolaryngology, The University of Iowa, Iowa City, Iowa 52242, USA
| | - Karen L Elliott
- Department of Biology & Department of Otolaryngology, The University of Iowa, Iowa City, Iowa 52242, USA
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Gillies N, Martín López LM, den Ouden OFC, Assink JD, Basille M, Clay TA, Clusella-Trullas S, Joo R, Weimerskirch H, Zampolli M, Zeyl JN, Patrick SC. Albatross movement suggests sensitivity to infrasound cues at sea. Proc Natl Acad Sci U S A 2023; 120:e2218679120. [PMID: 37812719 PMCID: PMC10589618 DOI: 10.1073/pnas.2218679120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 07/27/2023] [Indexed: 10/11/2023] Open
Abstract
The ways in which seabirds navigate over very large spatial scales remain poorly understood. While olfactory and visual information can provide guidance over short distances, their range is often limited to 100s km, far below the navigational capacity of wide-ranging animals such as albatrosses. Infrasound is a form of low-frequency sound that propagates for 1,000s km in the atmosphere. In marine habitats, its association with storms and ocean surface waves could in effect make it a useful cue for anticipating environmental conditions that favor or hinder flight or be associated with profitable foraging patches. However, behavioral responses of wild birds to infrasound remain untested. Here, we explored whether wandering albatrosses, Diomedea exulans, respond to microbarom infrasound at sea. We used Global Positioning System tracks of 89 free-ranging albatrosses in combination with acoustic modeling to investigate whether albatrosses preferentially orientate toward areas of 'loud' microbarom infrasound on their foraging trips. We found that in addition to responding to winds encountered in situ, albatrosses moved toward source regions associated with higher sound pressure levels. These findings suggest that albatrosses may be responding to long-range infrasonic cues. As albatrosses depend on winds and waves for soaring flight, infrasonic cues may help albatrosses to identify environmental conditions that allow them to energetically optimize flight over long distances. Our results shed light on one of the great unresolved mysteries in nature, navigation in seemingly featureless ocean environments.
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Affiliation(s)
- Natasha Gillies
- School of Environmental Sciences, University of Liverpool, LiverpoolL3 5DA, United Kingdom
| | - Lucía Martina Martín López
- School of Environmental Sciences, University of Liverpool, LiverpoolL3 5DA, United Kingdom
- Ipar Perspective Asociación Karabiondo Kalea, Bilbao48600, Spain
| | - Olivier F. C. den Ouden
- Research and Development Seismology and Acoustics, Royal Netherlands Meteorological Institute, Utrecht3731GA, Netherlands
- Department of Geoscience and Engineering, Delft University of Technology, Delft2628CD, Netherlands
| | - Jelle D. Assink
- Research and Development Seismology and Acoustics, Royal Netherlands Meteorological Institute, Utrecht3731GA, Netherlands
| | - Mathieu Basille
- Department of Wildlife Ecology and Conservation, Fort Lauderdale Research and Education Center, University of Florida, Davie, FL33314
| | - Thomas A. Clay
- School of Environmental Sciences, University of Liverpool, LiverpoolL3 5DA, United Kingdom
- Institute of Marine Sciences, University of California, Santa Cruz, CA95064
| | | | - Rocío Joo
- Global Fishing Watch, Washington, DC20036
| | - Henri Weimerskirch
- Ecology of Marine Birds and Mammals, Centre d’Étude Biologique de Chizé, Villiers-en-Bois79360, France
| | - Mario Zampolli
- International Monitoring System Division, Comprehensive Nuclear-Test-Ban Treaty Organization, Vienna1400, Austria
| | - Jeffrey N. Zeyl
- Department of Botany and Zoology, Stellenbosch University, Cape Town7602, South Africa
| | - Samantha C. Patrick
- School of Environmental Sciences, University of Liverpool, LiverpoolL3 5DA, United Kingdom
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Fritzsch B, Schultze HP, Elliott KL. The evolution of the various structures required for hearing in Latimeria and tetrapods. IBRO Neurosci Rep 2023; 14:325-341. [PMID: 37006720 PMCID: PMC10063410 DOI: 10.1016/j.ibneur.2023.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Sarcopterygians evolved around 415 Ma and have developed a unique set of features, including the basilar papilla and the cochlear aqueduct of the inner ear. We provide an overview that shows the morphological integration of the various parts needed for hearing, e.g., basilar papilla, tectorial membrane, cochlear aqueduct, lungs, and tympanic membranes. The lagena of the inner ear evolved from a common macula of the saccule several times. It is near this lagena where the basilar papilla forms in Latimeria and tetrapods. The basilar papilla is lost in lungfish, certain caecilians and salamanders, but is transformed into the cochlea of mammals. Hearing in bony fish and tetrapods involves particle motion to improve sound pressure reception within the ear but also works without air. Lungs evolved after the chondrichthyans diverged and are present in sarcopterygians and actinopterygians. Lungs open to the outside in tetraposomorph sarcopterygians but are transformed from a lung into a swim bladder in ray-finned fishes. Elasmobranchs, polypterids, and many fossil fishes have open spiracles. In Latimeria, most frogs, and all amniotes, a tympanic membrane covering the spiracle evolved independently. The tympanic membrane is displaced by pressure changes and enabled tetrapods to perceive airborne sound pressure waves. The hyomandibular bone is associated with the spiracle/tympanic membrane in actinopterygians and piscine sarcopterygians. In tetrapods, it transforms into the stapes that connects the oval window of the inner ear with the tympanic membrane and allows hearing at higher frequencies by providing an impedance matching and amplification mechanism. The three characters-basilar papilla, cochlear aqueduct, and tympanic membrane-are fluid related elements in sarcopterygians, which interact with a set of unique features in Latimeria. Finally, we explore the possible interaction between the unique intracranial joint, basicranial muscle, and an enlarged notochord that allows fluid flow to the foramen magnum and the cochlear aqueduct which houses a comparatively small brain.
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Affiliation(s)
- Bernd Fritzsch
- Department of Biology & Department of Otolaryngology, University of Iowa, IA, USA
- Correspondence to: Department of Biology & Department of Otolaryngology, University of Iowa, Iowa City, IA, 52242, USA.
| | | | - Karen L. Elliott
- Department of Biology & Department of Otolaryngology, University of Iowa, IA, USA
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Abstract
The ability to sense and localize sound is so advantageous for survival that it is difficult to understand the almost 100 million year gap separating the appearance of early tetrapods and the emergence of an impedance-matching tympanic middle ear - which we normally regard as a prerequisite for sensitive hearing on land - in their descendants. Recent studies of hearing in extant atympanate vertebrates have provided significant insights into the ancestral state(s) and the early evolution of the terrestrial tetrapod auditory system. These reveal a mechanism for sound pressure detection and directional hearing in 'earless' atympanate vertebrates that may be generalizable to all tetrapods, including the earliest terrestrial species. Here, we review the structure and function of vertebrate tympanic middle ears and highlight the multiple acquisition and loss events that characterize the complex evolutionary history of this important sensory structure. We describe extratympanic pathways for sound transmission to the inner ear and synthesize findings from recent studies to propose a general mechanism for hearing in 'earless' atympanate vertebrates. Finally, we integrate these studies with research on tympanate species that may also rely on extratympanic mechanisms for acoustic reception of infrasound (<20 Hz) and with studies on human bone conduction mechanisms of hearing.
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Affiliation(s)
- Grace Capshaw
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | | | - Catherine E Carr
- Department of Biology, University of Maryland, College Park, MD 20742, USA
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7
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Patrick SC, Assink JD, Basille M, Clusella-Trullas S, Clay TA, den Ouden OFC, Joo R, Zeyl JN, Benhamou S, Christensen-Dalsgaard J, Evers LG, Fayet AL, Köppl C, Malkemper EP, Martín López LM, Padget O, Phillips RA, Prior MK, Smets PSM, van Loon EE. Infrasound as a Cue for Seabird Navigation. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.740027] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Seabirds are amongst the most mobile of all animal species and spend large amounts of their lives at sea. They cross vast areas of ocean that appear superficially featureless, and our understanding of the mechanisms that they use for navigation remains incomplete, especially in terms of available cues. In particular, several large-scale navigational tasks, such as homing across thousands of kilometers to breeding sites, are not fully explained by visual, olfactory or magnetic stimuli. Low-frequency inaudible sound, i.e., infrasound, is ubiquitous in the marine environment. The spatio-temporal consistency of some components of the infrasonic wavefield, and the sensitivity of certain bird species to infrasonic stimuli, suggests that infrasound may provide additional cues for seabirds to navigate, but this remains untested. Here, we propose a framework to explore the importance of infrasound for navigation. We present key concepts regarding the physics of infrasound and review the physiological mechanisms through which infrasound may be detected and used. Next, we propose three hypotheses detailing how seabirds could use information provided by different infrasound sources for navigation as an acoustic beacon, landmark, or gradient. Finally, we reflect on strengths and limitations of our proposed hypotheses, and discuss several directions for future work. In particular, we suggest that hypotheses may be best tested by combining conceptual models of navigation with empirical data on seabird movements and in-situ infrasound measurements.
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Benedict L, Hardt B, Dargis L. Form and Function Predict Acoustic Transmission Properties of the Songs of Male and Female Canyon Wrens. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.722967] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
To function effectively, animal signals must transmit through the environment to receivers, and signal transmission properties depend on signal form. Here we investigated how the transmission of multiple parts of a well-studied signal, bird song, varies between males and females of one species. We hypothesized that male and female songs would have different transmission properties, reflecting known differences in song form and function. We further hypothesized that two parts of male song used differentially in broadcast singing and aggressive contests would transmit differently. Analyses included male and female songs from 20 pairs of canyon wrens (Catherpes mexicanus) played and re-recorded in species-typical habitat. We found that male song cascades used in broadcast singing propagated farther than female songs, with higher signal-to-noise ratios at distance. In contrast, we demonstrated relatively restricted propagation of the two vocalization types typically used in short-distance aggressive signaling, female songs and male “cheet” notes. Of the three tested signals, male “cheet” notes had the shortest modeled propagation distances. Male and female signals blurred similarly, with variable patterns of excess attenuation. Both male song parts showed more consistent transmission across the duration of the signal than did female songs. Song transmission, thus, varied by sex and reflected signal form and use context. Results support the idea that males and females of the same species can show distinctly different signal evolution trajectories. Sexual and social selection pressures can shape sex-specific signal transmission, even when males and females are communicating in shared physical environments.
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Elmer LK, Madliger CL, Blumstein DT, Elvidge CK, Fernández-Juricic E, Horodysky AZ, Johnson NS, McGuire LP, Swaisgood RR, Cooke SJ. Exploiting common senses: sensory ecology meets wildlife conservation and management. CONSERVATION PHYSIOLOGY 2021; 9:coab002. [PMID: 33815799 PMCID: PMC8009554 DOI: 10.1093/conphys/coab002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 10/27/2020] [Accepted: 01/06/2021] [Indexed: 05/21/2023]
Abstract
Multidisciplinary approaches to conservation and wildlife management are often effective in addressing complex, multi-factor problems. Emerging fields such as conservation physiology and conservation behaviour can provide innovative solutions and management strategies for target species and systems. Sensory ecology combines the study of 'how animals acquire' and process sensory stimuli from their environments, and the ecological and evolutionary significance of 'how animals respond' to this information. We review the benefits that sensory ecology can bring to wildlife conservation and management by discussing case studies across major taxa and sensory modalities. Conservation practices informed by a sensory ecology approach include the amelioration of sensory traps, control of invasive species, reduction of human-wildlife conflicts and relocation and establishment of new populations of endangered species. We illustrate that sensory ecology can facilitate the understanding of mechanistic ecological and physiological explanations underlying particular conservation issues and also can help develop innovative solutions to ameliorate conservation problems.
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Affiliation(s)
- Laura K Elmer
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental and Interdisciplinary Science, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Christine L Madliger
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental and Interdisciplinary Science, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - Daniel T Blumstein
- Department of Ecology and Evolutionary Biology, Institute of the Environment and Sustainability, University of California, Los Angeles, Los Angeles, CA 90095-1606, USA
| | - Chris K Elvidge
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental and Interdisciplinary Science, Carleton University, Ottawa, ON K1S 5B6, Canada
| | | | - Andrij Z Horodysky
- Department of Marine and Environmental Science, Hampton University, Hampton, VA 23668, USA
| | - Nicholas S Johnson
- USGS, Great Lakes Science Center, Hammond Bay Biological Station, Millersburg, MI 49759, USA
| | - Liam P McGuire
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Ronald R Swaisgood
- Institute for Conservation Research, San Diego Zoo Global, San Diego, CA 92027-7000, USA
| | - Steven J Cooke
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental and Interdisciplinary Science, Carleton University, Ottawa, ON K1S 5B6, Canada
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Hearing in Indian peafowl (Pavo cristatus): sensitivity to infrasound. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2020; 206:899-906. [PMID: 33025058 DOI: 10.1007/s00359-020-01446-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/31/2020] [Accepted: 09/12/2020] [Indexed: 10/23/2022]
Abstract
Despite the excitement that followed the report of infrasound sensitivity in pigeons 40 years ago, there has been limited followup, with only eleven species of birds having auditory thresholds at frequencies below 250 Hz. With such sparse data on low-frequency hearing, there is little understanding of why some birds hear very low frequencies while others do not. To begin to expand the phylogenetic and ecological sample of low-frequency hearing in birds, we determined the behavioral audiogram of the Indian peafowl, Pavo cristatus. Peafowl are thought to use low frequencies generated by the males' tail feathers and wing flutters during courtship displays, and their crest feathers are reported to resonate at infrasound frequencies. The peafowl were able to respond to frequencies as low as 4 Hz, and their hearing range at 60 dB SPL extended from 29 Hz to 7.065 kHz (7.9 octaves). Removing the crest feathers reduced sensitivity at their resonant frequencies by as much as 7.5 dB, indicating a modest contribution to detectability in that range. However, perforation of the tympanic membranes severely reduced sensitivity to low frequencies, indicating that sensitivity to low frequencies is mediated primarily by the ears and cannot be attributed to some other sensory modality.
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