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Watson SK, Filippi P, Gasparri L, Falk N, Tamer N, Widmer P, Manser M, Glock H. Optionality in animal communication: a novel framework for examining the evolution of arbitrariness. Biol Rev Camb Philos Soc 2022; 97:2057-2075. [PMID: 35818133 PMCID: PMC9795909 DOI: 10.1111/brv.12882] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 06/14/2022] [Accepted: 06/16/2022] [Indexed: 12/30/2022]
Abstract
A critical feature of language is that the form of words need not bear any perceptual similarity to their function - these relationships can be 'arbitrary'. The capacity to process these arbitrary form-function associations facilitates the enormous expressive power of language. However, the evolutionary roots of our capacity for arbitrariness, i.e. the extent to which related abilities may be shared with animals, is largely unexamined. We argue this is due to the challenges of applying such an intrinsically linguistic concept to animal communication, and address this by proposing a novel conceptual framework highlighting a key underpinning of linguistic arbitrariness, which is nevertheless applicable to non-human species. Specifically, we focus on the capacity to associate alternative functions with a signal, or alternative signals with a function, a feature we refer to as optionality. We apply this framework to a broad survey of findings from animal communication studies and identify five key dimensions of communicative optionality: signal production, signal adjustment, signal usage, signal combinatoriality and signal perception. We find that optionality is widespread in non-human animals across each of these dimensions, although only humans demonstrate it in all five. Finally, we discuss the relevance of optionality to behavioural and cognitive domains outside of communication. This investigation provides a powerful new conceptual framework for the cross-species investigation of the origins of arbitrariness, and promises to generate original insights into animal communication and language evolution more generally.
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Affiliation(s)
- Stuart K. Watson
- Department of Comparative Language ScienceUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichWinterthurerstrasse 1908057ZurichSwitzerland
| | - Piera Filippi
- Department of Comparative Language ScienceUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of PhilosophyUniversity of ZurichZurichbergstrasse 438044ZürichSwitzerland
| | - Luca Gasparri
- Department of PhilosophyUniversity of ZurichZurichbergstrasse 438044ZürichSwitzerland,Univ. Lille, CNRS, UMR 8163 – STL – Savoirs Textes LangageF‐59000LilleFrance
| | - Nikola Falk
- Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichWinterthurerstrasse 1908057ZurichSwitzerland
| | - Nicole Tamer
- Department of Comparative Language ScienceUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland
| | - Paul Widmer
- Department of Comparative Language ScienceUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland
| | - Marta Manser
- Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichWinterthurerstrasse 1908057ZurichSwitzerland
| | - Hans‐Johann Glock
- Center for the Interdisciplinary Study of Language EvolutionUniversity of ZurichAffolternstrasse 568050ZürichSwitzerland,Department of PhilosophyUniversity of ZurichZurichbergstrasse 438044ZürichSwitzerland
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2
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Vernes SC, Devanna P, Hörpel SG, Alvarez van Tussenbroek I, Firzlaff U, Hagoort P, Hiller M, Hoeksema N, Hughes GM, Lavrichenko K, Mengede J, Morales AE, Wiesmann M. The pale spear-nosed bat: A neuromolecular and transgenic model for vocal learning. Ann N Y Acad Sci 2022; 1517:125-142. [PMID: 36069117 PMCID: PMC9826251 DOI: 10.1111/nyas.14884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Vocal learning, the ability to produce modified vocalizations via learning from acoustic signals, is a key trait in the evolution of speech. While extensively studied in songbirds, mammalian models for vocal learning are rare. Bats present a promising study system given their gregarious natures, small size, and the ability of some species to be maintained in captive colonies. We utilize the pale spear-nosed bat (Phyllostomus discolor) and report advances in establishing this species as a tractable model for understanding vocal learning. We have taken an interdisciplinary approach, aiming to provide an integrated understanding across genomics (Part I), neurobiology (Part II), and transgenics (Part III). In Part I, we generated new, high-quality genome annotations of coding genes and noncoding microRNAs to facilitate functional and evolutionary studies. In Part II, we traced connections between auditory-related brain regions and reported neuroimaging to explore the structure of the brain and gene expression patterns to highlight brain regions. In Part III, we created the first successful transgenic bats by manipulating the expression of FoxP2, a speech-related gene. These interdisciplinary approaches are facilitating a mechanistic and evolutionary understanding of mammalian vocal learning and can also contribute to other areas of investigation that utilize P. discolor or bats as study species.
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Affiliation(s)
- Sonja C. Vernes
- School of BiologyUniversity of St AndrewsSt AndrewsUK,Neurogenetics of Vocal Communication GroupMax Planck Institute for PsycholinguisticsNijmegenThe Netherlands
| | - Paolo Devanna
- School of BiologyUniversity of St AndrewsSt AndrewsUK,Neurogenetics of Vocal Communication GroupMax Planck Institute for PsycholinguisticsNijmegenThe Netherlands
| | - Stephen Gareth Hörpel
- School of BiologyUniversity of St AndrewsSt AndrewsUK,Neurogenetics of Vocal Communication GroupMax Planck Institute for PsycholinguisticsNijmegenThe Netherlands,TUM School of Life SciencesTechnical University of MunichFreisingGermany
| | - Ine Alvarez van Tussenbroek
- School of BiologyUniversity of St AndrewsSt AndrewsUK,Neurogenetics of Vocal Communication GroupMax Planck Institute for PsycholinguisticsNijmegenThe Netherlands
| | - Uwe Firzlaff
- TUM School of Life SciencesTechnical University of MunichFreisingGermany
| | - Peter Hagoort
- Neurobiology of Language DepartmentMax Planck Institute for PsycholinguisticsNijmegenThe Netherlands
| | - Michael Hiller
- LOEWE Centre for Translational Biodiversity Genomics, Faculty of Biosciences, Senckenberg Research Institute, Goethe‐UniversityFrankfurtGermany
| | - Nienke Hoeksema
- Neurogenetics of Vocal Communication GroupMax Planck Institute for PsycholinguisticsNijmegenThe Netherlands,Neurobiology of Language DepartmentMax Planck Institute for PsycholinguisticsNijmegenThe Netherlands
| | - Graham M. Hughes
- School of Biology and Environmental ScienceUniversity College DublinBelfieldIreland
| | - Ksenia Lavrichenko
- Neurogenetics of Vocal Communication GroupMax Planck Institute for PsycholinguisticsNijmegenThe Netherlands
| | - Janine Mengede
- Neurogenetics of Vocal Communication GroupMax Planck Institute for PsycholinguisticsNijmegenThe Netherlands
| | - Ariadna E. Morales
- LOEWE Centre for Translational Biodiversity Genomics, Faculty of Biosciences, Senckenberg Research Institute, Goethe‐UniversityFrankfurtGermany
| | - Maximilian Wiesmann
- Department of Medical ImagingAnatomyRadboud University Medical Center, Donders Institute for Brain, Cognition & Behavior, Center for Medical Neuroscience, Preclinical Imaging Center PRIME, Radboud Alzheimer CenterNijmegenThe Netherlands
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3
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Pastyrik JD, Firzlaff U. Object specific adaptation in the auditory cortex of bats. J Neurophysiol 2022; 128:556-567. [PMID: 35946795 DOI: 10.1152/jn.00151.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To identify behaviourally relevant sounds is an important function of the auditory system. Echolocating bats have to negotiate a wealth of sounds in the context of navigation and foraging. They must be able to detect relatively rare but behaviourally important echoes and segregate them from a large number of unimportant background echoes. For this, the bat auditory system might rely on neural deviance detection, a process influencing the excitability of a neuron depending on the frequency of occurrence of a stimulus. To investigate neural deviance detection in the auditory cortex (AC) of anaesthetised bats (Phyllostomus discolor), we designed sequences of repetitive naturalistic virtual echoes differing in spectro-temporal envelope, resembling those bats might perceive in their natural environment. In these sequences, one echo (standard) was repeated ten times and another echo (deviant) was presented at the end. Temporal intervals between echoes within the sequences varied. Our results show, that neurons in the AC of the bat P. discolor are sensitive to novel virtual echoes presented at the end of these repetitive sequences: In 49 % (62/126) of cortical neurons, extracellularly recorded responses adapted to the standard echo, but showed a strong response to the finally presented deviant echo. This effect depended strongly on the temporal intervals between echoes, with stronger adaptation at shorter intervals. This type of response behavior might represent a form of neuronal deviance detection in the AC that could help the bats to detect echoes of novel and potentially important objects within a stream of homogeneous background echoes.
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Affiliation(s)
- Jan David Pastyrik
- Chair of Zoology, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Uwe Firzlaff
- Chair of Zoology, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
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4
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Lattenkamp EZ, Linnenschmidt M, Mardus E, Vernes SC, Wiegrebe L, Schutte M. The vocal development of the pale spear-nosed bat is dependent on auditory feedback. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200253. [PMID: 34482731 PMCID: PMC8419572 DOI: 10.1098/rstb.2020.0253] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Human vocal development and speech learning require acoustic feedback, and humans who are born deaf do not acquire a normal adult speech capacity. Most other mammals display a largely innate vocal repertoire. Like humans, bats are thought to be one of the few taxa capable of vocal learning as they can acquire new vocalizations by modifying vocalizations according to auditory experiences. We investigated the effect of acoustic deafening on the vocal development of the pale spear-nosed bat. Three juvenile pale spear-nosed bats were deafened, and their vocal development was studied in comparison with an age-matched, hearing control group. The results show that during development the deafened bats increased their vocal activity, and their vocalizations were substantially altered, being much shorter, higher in pitch, and more aperiodic than the vocalizations of the control animals. The pale spear-nosed bat relies on auditory feedback for vocal development and, in the absence of auditory input, species-atypical vocalizations are acquired. This work serves as a basis for further research using the pale spear-nosed bat as a mammalian model for vocal learning, and contributes to comparative studies on hearing impairment across species. This article is part of the theme issue 'Vocal learning in animals and humans'.
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Affiliation(s)
- Ella Z Lattenkamp
- Department Biology II, Ludwig Maximilians University Munich, Martinsried, Germany.,Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Meike Linnenschmidt
- Department Biology II, Ludwig Maximilians University Munich, Martinsried, Germany
| | - Eva Mardus
- Department Biology II, Ludwig Maximilians University Munich, Martinsried, Germany.,Graduate School of Systemic Neurosciences, Ludwig Maximilians University Munich, Martinsried, Germany
| | - Sonja C Vernes
- Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.,School of Biology, St Andrews University, St Andrews, UK
| | - Lutz Wiegrebe
- Department Biology II, Ludwig Maximilians University Munich, Martinsried, Germany
| | - Michael Schutte
- Department Biology II, Ludwig Maximilians University Munich, Martinsried, Germany.,Graduate School of Systemic Neurosciences, Ludwig Maximilians University Munich, Martinsried, Germany
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5
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Abstract
Vocal production learning, the ability to modify the structure of vocalizations as a result of hearing those of others, has been studied extensively in birds but less attention has been given to its occurrence in mammals. We summarize the available evidence for vocal learning in mammals from the last 25 years, updating earlier reviews on the subject. The clearest evidence comes from cetaceans, pinnipeds, elephants and bats where species have been found to copy artificial or human language sounds, or match acoustic models of different sound types. Vocal convergence, in which parameter adjustments within one sound type result in similarities between individuals, occurs in a wider range of mammalian orders with additional evidence from primates, mole-rats, goats and mice. Currently, the underlying mechanisms for convergence are unclear with vocal production learning but also usage learning or matching physiological states being possible explanations. For experimental studies, we highlight the importance of quantitative comparisons of seemingly learned sounds with vocal repertoires before learning started or with species repertoires to confirm novelty. Further studies on the mammalian orders presented here as well as others are needed to explore learning skills and limitations in greater detail. This article is part of the theme issue 'Vocal learning in animals and humans'.
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Affiliation(s)
- Vincent M Janik
- Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews KY16 8LB, UK
| | - Mirjam Knörnschild
- Museum für Naturkunde, Leibniz-Institute for Evolution and Biodiversity Science, Berlin, Germany.,Animal Behavior Lab, Freie Universität, Berlin, Germany.,Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
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6
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Lattenkamp EZ, Hörpel SG, Mengede J, Firzlaff U. A researcher's guide to the comparative assessment of vocal production learning. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200237. [PMID: 34482725 DOI: 10.1098/rstb.2020.0237] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Vocal production learning (VPL) is the capacity to learn to produce new vocalizations, which is a rare ability in the animal kingdom and thus far has only been identified in a handful of mammalian taxa and three groups of birds. Over the last few decades, approaches to the demonstration of VPL have varied among taxa, sound production systems and functions. These discrepancies strongly impede direct comparisons between studies. In the light of the growing number of experimental studies reporting VPL, the need for comparability is becoming more and more pressing. The comparative evaluation of VPL across studies would be facilitated by unified and generalized reporting standards, which would allow a better positioning of species on any proposed VPL continuum. In this paper, we specifically highlight five factors influencing the comparability of VPL assessments: (i) comparison to an acoustic baseline, (ii) comprehensive reporting of acoustic parameters, (iii) extended reporting of training conditions and durations, (iv) investigating VPL function via behavioural, perception-based experiments and (v) validation of findings on a neuronal level. These guidelines emphasize the importance of comparability between studies in order to unify the field of vocal learning. This article is part of the theme issue 'Vocal learning in animals and humans'.
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Affiliation(s)
- Ella Z Lattenkamp
- Division of Neurobiology, Department of Biology II, LMU Munich, Germany.,Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Stephen G Hörpel
- Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.,Department of Animal Sciences, Chair of Zoology, TU Munich, Germany
| | - Janine Mengede
- Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Uwe Firzlaff
- Department of Animal Sciences, Chair of Zoology, TU Munich, Germany
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7
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Vernes SC, Kriengwatana BP, Beeck VC, Fischer J, Tyack PL, ten Cate C, Janik VM. The multi-dimensional nature of vocal learning. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200236. [PMID: 34482723 PMCID: PMC8419582 DOI: 10.1098/rstb.2020.0236] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/26/2021] [Indexed: 01/02/2023] Open
Abstract
How learning affects vocalizations is a key question in the study of animal communication and human language. Parallel efforts in birds and humans have taught us much about how vocal learning works on a behavioural and neurobiological level. Subsequent efforts have revealed a variety of cases among mammals in which experience also has a major influence on vocal repertoires. Janik and Slater (Anim. Behav.60, 1-11. (doi:10.1006/anbe.2000.1410)) introduced the distinction between vocal usage and production learning, providing a general framework to categorize how different types of learning influence vocalizations. This idea was built on by Petkov and Jarvis (Front. Evol. Neurosci.4, 12. (doi:10.3389/fnevo.2012.00012)) to emphasize a more continuous distribution between limited and more complex vocal production learners. Yet, with more studies providing empirical data, the limits of the initial frameworks become apparent. We build on these frameworks to refine the categorization of vocal learning in light of advances made since their publication and widespread agreement that vocal learning is not a binary trait. We propose a novel classification system, based on the definitions by Janik and Slater, that deconstructs vocal learning into key dimensions to aid in understanding the mechanisms involved in this complex behaviour. We consider how vocalizations can change without learning, and a usage learning framework that considers context specificity and timing. We identify dimensions of vocal production learning, including the copying of auditory models (convergence/divergence on model sounds, accuracy of copying), the degree of change (type and breadth of learning) and timing (when learning takes place, the length of time it takes and how long it is retained). We consider grey areas of classification and current mechanistic understanding of these behaviours. Our framework identifies research needs and will help to inform neurobiological and evolutionary studies endeavouring to uncover the multi-dimensional nature of vocal learning. This article is part of the theme issue 'Vocal learning in animals and humans'.
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Affiliation(s)
- Sonja C. Vernes
- School of Biology, University of St Andrews, St Andrews, UK
- Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | | | - Veronika C. Beeck
- Department of Behavioural and Cognitive Biology, University of Vienna, Vienna, Austria
| | - Julia Fischer
- Cognitive Ethology Laboratory, German Primate Centre, Göttingen, Germany
- Department of Primate Cognition, Georg-August-University Göttingen, Göttingen, Germany
| | - Peter L. Tyack
- School of Biology, University of St Andrews, St Andrews, UK
| | - Carel ten Cate
- Institute of Biology, Leiden University, Leiden, The Netherlands
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8
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Hörpel SG, Baier AL, Peremans H, Reijniers J, Wiegrebe L, Firzlaff U. Communication breakdown: Limits of spectro-temporal resolution for the perception of bat communication calls. Sci Rep 2021; 11:13708. [PMID: 34211004 PMCID: PMC8249457 DOI: 10.1038/s41598-021-92842-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 06/14/2021] [Indexed: 02/06/2023] Open
Abstract
During vocal communication, the spectro-temporal structure of vocalizations conveys important contextual information. Bats excel in the use of sounds for echolocation by meticulous encoding of signals in the temporal domain. We therefore hypothesized that for social communication as well, bats would excel at detecting minute distortions in the spectro-temporal structure of calls. To test this hypothesis, we systematically introduced spectro-temporal distortion to communication calls of Phyllostomus discolor bats. We broke down each call into windows of the same length and randomized the phase spectrum inside each window. The overall degree of spectro-temporal distortion in communication calls increased with window length. Modelling the bat auditory periphery revealed that cochlear mechanisms allow discrimination of fast spectro-temporal envelopes. We evaluated model predictions with experimental psychophysical and neurophysiological data. We first assessed bats' performance in discriminating original versions of calls from increasingly distorted versions of the same calls. We further examined cortical responses to determine additional specializations for call discrimination at the cortical level. Psychophysical and cortical responses concurred with model predictions, revealing discrimination thresholds in the range of 8-15 ms randomization-window length. Our data suggest that specialized cortical areas are not necessary to impart psychophysical resilience to temporal distortion in communication calls.
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Affiliation(s)
- Stephen Gareth Hörpel
- Chair of Zoology, School of Life Sciences, Technical University of Munich, Liesel-Beckmann-Str. 4, 85354, Freising, Germany.
- Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.
| | - A Leonie Baier
- Chair of Zoology, School of Life Sciences, Technical University of Munich, Liesel-Beckmann-Str. 4, 85354, Freising, Germany
- Department Biology II, Ludwig Maximilians University Munich, Großhaderner Strasse 2, 82152, Martinsried, Germany
| | - Herbert Peremans
- Department of Engineering Management, Faculty of Business and Economics, University of Antwerp, 2000, Antwerp, Belgium
| | - Jonas Reijniers
- Department of Engineering Management, Faculty of Business and Economics, University of Antwerp, 2000, Antwerp, Belgium
| | - Lutz Wiegrebe
- Department Biology II, Ludwig Maximilians University Munich, Großhaderner Strasse 2, 82152, Martinsried, Germany
| | - Uwe Firzlaff
- Chair of Zoology, School of Life Sciences, Technical University of Munich, Liesel-Beckmann-Str. 4, 85354, Freising, Germany
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9
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González-Palomares E, López-Jury L, Wetekam J, Kiai A, García-Rosales F, Hechavarria JC. Male Carollia perspicillata bats call more than females in a distressful context. ROYAL SOCIETY OPEN SCIENCE 2021; 8:202336. [PMID: 34040789 PMCID: PMC8113905 DOI: 10.1098/rsos.202336] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 04/16/2021] [Indexed: 06/12/2023]
Abstract
Distress calls are a vocalization type widespread across the animal kingdom, emitted when the animals are under duress, e.g. when captured by a predator. Here, we report on an observation we came across serendipitously while recording distress calls from the bat species Carollia perspicillata, i.e. the existence of sex difference in the distress calling behaviour of this species. We show that in C. perspicillata bats, males are more likely to produce distress vocalizations than females when hand-held. Male bats call more, their calls are louder, harsher (faster amplitude modulated) and cover lower carrier frequencies than female vocalizations. We discuss our results within a framework of potential hormonal, neurobiological and behavioural differences that could explain our findings, and open multiple paths to continue the study of sex-related differences in vocal behaviour in bats.
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Affiliation(s)
| | - Luciana López-Jury
- Institute for Cell Biology and Neuroscience, Goethe University, 60438 Frankfurt am Main, Germany
| | - Johannes Wetekam
- Institute for Cell Biology and Neuroscience, Goethe University, 60438 Frankfurt am Main, Germany
| | - Ava Kiai
- Institute for Cell Biology and Neuroscience, Goethe University, 60438 Frankfurt am Main, Germany
| | - Francisco García-Rosales
- Institute for Cell Biology and Neuroscience, Goethe University, 60438 Frankfurt am Main, Germany
| | - Julio C. Hechavarria
- Institute for Cell Biology and Neuroscience, Goethe University, 60438 Frankfurt am Main, Germany
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10
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O'Rourke T, Martins PT, Asano R, Tachibana RO, Okanoya K, Boeckx C. Capturing the Effects of Domestication on Vocal Learning Complexity. Trends Cogn Sci 2021; 25:462-474. [PMID: 33810982 DOI: 10.1016/j.tics.2021.03.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 03/08/2021] [Accepted: 03/08/2021] [Indexed: 11/28/2022]
Abstract
Domesticated and vocal learning species can serve as informative model organisms for the reduction of reactive aggression and emergence of speech in our lineage. Amidst mounting evidence that domestication modifies vocal repertoires across different species, we focus on the domesticated Bengalese finch, which has a more complex song than the wild-type white-rumped munia. Our explanation for this effect revolves around the glutamate neurotransmitter system. Glutamate signaling (i) is implicated in birdsong learning, (ii) controls dopamine activity in neural circuits crucial for vocal learning, (iii) is disproportionately targeted in the evolution of domesticates, and (iv) regulates stress responses and aggressive behaviors attenuated under domestication. We propose that attenuated excitation of stress-related neural circuits potentiates vocal learning via altered dopaminergic signaling.
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Affiliation(s)
- Thomas O'Rourke
- Section of General Linguistics, University of Barcelona, 08007 Barcelona, Spain; University of Barcelona Institute for Complex Systems (UBICS), 08028 Barcelona, Spain
| | - Pedro Tiago Martins
- Section of General Linguistics, University of Barcelona, 08007 Barcelona, Spain; University of Barcelona Institute for Complex Systems (UBICS), 08028 Barcelona, Spain
| | - Rie Asano
- Department of Systematic Musicology, University of Cologne, 50923 Cologne, Germany
| | - Ryosuke O Tachibana
- Center for Evolutionary Cognitive Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 153-8902 Tokyo, Japan
| | - Kazuo Okanoya
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 153-8902 Tokyo, Japan
| | - Cedric Boeckx
- Section of General Linguistics, University of Barcelona, 08007 Barcelona, Spain; University of Barcelona Institute for Complex Systems (UBICS), 08028 Barcelona, Spain; Catalan Institute for Advanced Studies and Research (ICREA), 08010 Barcelona, Spain.
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11
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Knörnschild M, Fernandez AA. Do Bats Have the Necessary Prerequisites for Symbolic Communication? Front Psychol 2020; 11:571678. [PMID: 33262725 PMCID: PMC7688458 DOI: 10.3389/fpsyg.2020.571678] [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: 06/11/2020] [Accepted: 10/12/2020] [Indexed: 11/20/2022] Open
Abstract
Training animals such as apes, gray parrots, or dolphins that communicate via arbitrary symbols with humans has revealed astonishing mental capacities that may have otherwise gone unnoticed. Albeit bats have not yet been trained to communicate via symbols with humans, we are convinced that some species, especially captive Pteropodid bats ("flying foxes"), show the potential to master this cognitive task. Here, we briefly review what is known about bats' cognitive skills that constitute relevant prerequisites for symbolic communication with humans. We focus on social learning in general, trainability by humans, associative learning from humans, imitation, vocal production learning and usage learning, and social knowledge. Moreover, we highlight potential training paradigms that could be used to elicit simple "symbolic" bat-human communication, i.e., training bats to select arbitrary symbols on a touchscreen to elicit a desired behavior of the human caregiver. Touchscreen-proficient bats could participate in cognition research, e.g., to study their numerical competence or categorical perception, to further elucidate how nonhuman animals learn and perceive the world.
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Affiliation(s)
- Mirjam Knörnschild
- Museum für Naturkunde, Leibniz-Institute for Evolution and Biodiversity Science, Berlin, Germany
- Animal Behavior Lab, Freie Universität, Berlin, Germany
- Smithsonian Tropical Research Institute, Ancón, Panama
| | - Ahana A. Fernandez
- Museum für Naturkunde, Leibniz-Institute for Evolution and Biodiversity Science, Berlin, Germany
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12
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Garcia M, Ravignani A. Acoustic allometry and vocal learning in mammals. Biol Lett 2020; 16:20200081. [PMID: 32634374 PMCID: PMC7423041 DOI: 10.1098/rsbl.2020.0081] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 06/11/2020] [Indexed: 12/15/2022] Open
Abstract
Acoustic allometry is the study of how animal vocalizations reflect their body size. A key aim of this research is to identify outliers to acoustic allometry principles and pinpoint the evolutionary origins of such outliers. A parallel strand of research investigates species capable of vocal learning, the experience-driven ability to produce novel vocal signals through imitation or modification of existing vocalizations. Modification of vocalizations is a common feature found when studying both acoustic allometry and vocal learning. Yet, these two fields have only been investigated separately to date. Here, we review and connect acoustic allometry and vocal learning across mammalian clades, combining perspectives from bioacoustics, anatomy and evolutionary biology. Based on this, we hypothesize that, as a precursor to vocal learning, some species might have evolved the capacity for volitional vocal modulation via sexual selection for 'dishonest' signalling. We provide preliminary support for our hypothesis by showing significant associations between allometric deviation and vocal learning in a dataset of 164 mammals. Our work offers a testable framework for future empirical research linking allometric principles with the evolution of vocal learning.
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Affiliation(s)
- Maxime Garcia
- Animal Behaviour, Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8051 Zurich, Switzerland
- Center for the Interdisciplinary Study of Language Evolution, University of Zurich, 8032 Zurich, Switzerland
| | - Andrea Ravignani
- Comparative Bioacoustics Group, Max Planck Institute for Psycholinguistics, Wundtlaan 1, 6525 XD Nijmegen, The Netherlands
- Research Department, Sealcentre Pieterburen, Hoofdstraat 94a, 9968 AG Pieterburen, The Netherlands
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Lattenkamp EZ, Vernes SC, Wiegrebe L. Vocal production learning in the pale spear-nosed bat, Phyllostomus discolor. Biol Lett 2020; 16:20190928. [PMID: 32289244 PMCID: PMC7211467 DOI: 10.1098/rsbl.2019.0928] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Vocal production learning (VPL), or the ability to modify vocalizations through the imitation of sounds, is a rare trait in the animal kingdom. While humans are exceptional vocal learners, few other mammalian species share this trait. Owing to their singular ecology and lifestyle, bats are highly specialized for the precise emission and reception of acoustic signals. This specialization makes them ideal candidates for the study of vocal learning, and several bat species have previously shown evidence supportive of vocal learning. Here we use a sophisticated automated set-up and a contingency training paradigm to explore the vocal learning capacity of pale spear-nosed bats. We show that these bats are capable of directional change of the fundamental frequency of their calls according to an auditory target. With this study, we further highlight the importance of bats for the study of vocal learning and provide evidence for the VPL capacity of the pale spear-nosed bat.
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Affiliation(s)
- Ella Z Lattenkamp
- Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.,Division of Neurobiology, Ludwig-Maximilians University Munich, Germany
| | - Sonja C Vernes
- Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - Lutz Wiegrebe
- Division of Neurobiology, Ludwig-Maximilians University Munich, Germany
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