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![Relationship between acoustic characteristics of grunts and body size in hamadryas baboons. A: Fundamental frequency versus body size; B: formant dispersion versus body size. Redrawn from Pfefferle and Fischer [2006], with permission from Elsevier. Formant dispersion was recalculated according to Reby and McComb [2003].](profile/Julia-Fischer-4/publication/236206746/figure/fig5/AS:278952913457167@1443518965462/Relationship-between-acoustic-characteristics-of-grunts-and-body-size-in-hamadryas.png)
Relationship between acoustic characteristics of grunts and body size in hamadryas baboons. A: Fundamental frequency versus body size; B: formant dispersion versus body size. Redrawn from Pfefferle and Fischer [2006], with permission from Elsevier. Formant dispersion was recalculated according to Reby and McComb [2003].
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Acoustic analyses of primate vocalizations as well as playback experiments are staple methods in primatology. Acoustic analyses have been used to investigate the influence of factors such as individuality, context, sex, age, and size on variation in calls. More recent studies have expanded our knowledge on the effects of phylogenetic relatedness an...
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Context 1
... [1997] found a high correlation between the actual VTL as measured by radioscintigraphy (r ¼ 0.915 with oral VTL and 0.852 with the nasal VTL). Hamadryas baboon grunts, in contrast, re- vealed a tight correlation between fundamental frequency and body size ( Fig. 3A), while the correla- tion between body size and formant dispersion was less strong (Fig. 3B) [Pfefferle & Fischer, 2006]. There is some danger of circular reasoning with LPC analyses, as the number of coefficients is derived from (theoretical) assumptions of the vocal tract length. These in turn determine the number of formants, and ...
Context 2
... found a high correlation between the actual VTL as measured by radioscintigraphy (r ¼ 0.915 with oral VTL and 0.852 with the nasal VTL). Hamadryas baboon grunts, in contrast, re- vealed a tight correlation between fundamental frequency and body size ( Fig. 3A), while the correla- tion between body size and formant dispersion was less strong (Fig. 3B) [Pfefferle & Fischer, 2006]. There is some danger of circular reasoning with LPC analyses, as the number of coefficients is derived from (theoretical) assumptions of the vocal tract length. These in turn determine the number of formants, and formant spacing, which is then sometimes used to infer VTL. Setting rather arbi- trary ...
Citations
... Playback experiments are frequently used in the study of animal communication as a controlled approach to reveal the underlying mechanisms and functional implications of specific call types (Douglas and Mennill 2010;Fischer et al. 2013;Prat et al. 2015). These methodologies typically involve broadcasting a chosen sound or call to the target species and subsequently observing and analyzing the elicited vocal or behavioral responses. ...
Manatees exhibit diverse vocalizations in various behavioral contexts, but the exact role of these sounds, particularly in terms of sex-based distinctions, remains elusive. This study sought to discern the behavioral and vocal responses of two subspecies of captive West Indian manatees (Trichechus manatus) to different call types (squeaks and squeals) to determine whether differences are related to the sex of the signaler. In Mexico, four female Antillean manatees (Trichechus manatus manatus) were subjected to playbacks, while in Florida, two male Florida manatees (Trichechus manatus latirostris) were used for a parallel experiment. Vocal responses were captured using two hydrophones, with an underwater speaker system facilitating the playback. Video footage was collected to observe behavioral changes in response to playback. Results indicated that neither male nor female manatees increased the number of calls, changed call type, or altered acoustic parameters regardless of call type or whether the sound played was male or female. Likewise, neither males nor females significantly altered their behavior or movement towards the speaker in response to male or female calls, or call type. However, individual Antillean manatees exhibited variation in their behavioral responses to playback of conspecific vocalizations. The results suggest that manatees may not distinguish between the sex of callers.
... A variety of vocalizations, including those previously observed in their natural environment, were played to assess how the boars would respond to their own calls as well as other recorded sounds. This methodology aligns with bioacoustic field protocols established in primate research and broader behavioral studies (Fischer et al., 2013) [2] , (Rosenthal et al., 2010) [3] . ...
... A variety of vocalizations, including those previously observed in their natural environment, were played to assess how the boars would respond to their own calls as well as other recorded sounds. This methodology aligns with bioacoustic field protocols established in primate research and broader behavioral studies (Fischer et al., 2013) [2] , (Rosenthal et al., 2010) [3] . ...
The Wild Boar Research, initiated in 2018, has aimed to enhance our understanding of wildlife behavior, with a particular focus on the vocalization patterns of wild boars (Sus scrofa). Phase 4 of this study advances our investigation into the communication of wild boars by analyzing a combination of sound and video data. This phase involves the identification and categorization of specific vocalizations, with the goal of learning the boar's "language." Through the synthesis of these vocalizations, we are testing the responsiveness of wild boars to recorded sounds played back to them in their natural habitat. This phase represents a novel approach to wildlife behavior research, contributing to the broader field of animal communication and offering insights into interspecies interaction. The study's findings may open new avenues for conservation strategies and wildlife management. Introduction Acoustic signaling in non-human mammals serves a diverse range of ecological and social functions. In Sus scrofa, vocalizations represent a critical component of intra-specific communication. The species exhibits context-specific call types that vary in frequency, pitch, amplitude, and rhythmic structure. These vocalizations are not only reflective of emotional states and social intentions but are also essential for maintaining group cohesion, coordinating behaviors, and mediating conflict (Garcia et al., 2016) [1]. The Wild Boar Research, initiated in 2018, is a multi-phase study designed to deepen our understanding of the behavior, communication, and management of wild boars (Sus scrofa). Over the course of the research, various aspects of wild boar ecology and behavior have been explored, with a focus on creating practical solutions to minimize human-wildlife conflicts. The research is structured into four phases, each building upon the previous to provide a comprehensive approach to wild boar behavior and management.
... However, environmental and methodological factors may have also influenced our results. While we conducted playback experiments under comparable weather conditions (no experiments were conducted during rain or strong winds), finer-scale factors such as sound propagation affected by wind or vegetation could have played a role (Fischer et al. 2013). Additionally, one could question the utility of using sound playbacks to simulate predator presence. ...
Animals' assessments of predation risk are influenced by a variety of external and internal factors, including predator space use. However, it remains unclear what variables mediate prey species behavior within a landscape where predation risk is heterogeneous. To address this, we employed three assays to examine zebra (Equus quagga) responses to varying predation risk in a multiple‐use area of northern Tanzania: (1) quantifying head‐up posture as a proxy for vigilance through direct behavioral observation in areas of high and low likelihood of lion (Panthera leo) presence, (2) quantifying head‐up posture as a proxy for vigilance when exposed to a lion roar playback, and (3) measuring flight initiation distances (FIDs) when approached by a person. Using generalized linear (mixed) models, we tested how lion space use and habitat type (as proxies for predation risk), normalized difference vegetation index (NDVI, as proxy for primary productivity), time of the day, and zebra‐related variables (sex‐age category, zebra herd size, group size including heterospecifics, and location within the herd) influenced vigilance and flight responses. We found that (1) neither vigilance nor FID were markedly influenced by estimated lion space use, habitat type, and NDVI; (2) vigilance decreased with group size, was lower for zebras positioned centrally in the herd, and during midday; (3) FID increased with a greater number of associated heterospecifics; and (4) zebras increased vigilance when exposed to lion roar playbacks, irrespective of lion space use. These findings suggest that zebra vigilance and flight behavior are not necessarily mediated by spatial variation in apparent predation risk but instead reflect a strategy of maintaining a consistent monitoring of possible threats across the landscape. Rather than relying on spatial clues alone, zebras primarily mitigate predation risk by increasing group size and associating with other species.
... Several precautions were taken to limit habituation and confounding factors [16,46,58]. The environmental conditions and study subjects' habituation to the researchers allowed the distance gelada-speaker to be kept as constant as possible during the different playback sessions (~15 metres). ...
Recognizing vocal behaviours intended to benefit others is a crucial yet understudied social skill. Primates with rich vocal repertoires and complex societies are excellent models to track the evolution of such capacity. Here, we exposed wild geladas (Theropithecus gelada) to vocal exchanges between unfamiliar female victim screams and male affiliative calls. The stimuli were arranged in sequences either simulating vocal affiliation towards victims (scream-affiliative call) or violating such order (affiliative call-scream), with varying emotional arousal conveyed by the affiliative call type. Measuring gazing activity towards the loudspeaker and the interruptions of feeding, we show that monkeys were sensitive to the sequential order in vocal exchanges as well as to the emotional arousal conveyed by affiliative calls. Our field study suggests a prosocial use of vocalizations in wild monkeys and reveals that foundational cognitive elements for processing vocal exchanges as meaningful third-party interactions may have existed in our common ancestors with monkeys.
... Bioacoustics, the study of sound production and reception in animals, aims to understand animal behavior (Fischer et al., 2013), monitor biodiversity (Stowell, 2022), and model the mechanisms of sound production and reception used in animal communication (Bradbury & Vehrencamp, 1998). It plays a vital role in conservation and ecological research, as animal vocalizations provide critical insights into ecosystem health, species interactions, and population dynamics. ...
Large language models (LLMs) prompted with text and audio represent the state of the art in various auditory tasks, including speech, music, and general audio, showing emergent abilities on unseen tasks. However, these capabilities have yet to be fully demonstrated in bioacoustics tasks, such as detecting animal vocalizations in large recordings, classifying rare and endangered species, and labeling context and behavior - tasks that are crucial for conservation, biodiversity monitoring, and the study of animal behavior. In this work, we present NatureLM-audio, the first audio-language foundation model specifically designed for bioacoustics. Our carefully curated training dataset comprises text-audio pairs spanning a diverse range of bioacoustics, speech, and music data, designed to address the challenges posed by limited annotated datasets in the field. We demonstrate successful transfer of learned representations from music and speech to bioacoustics, and our model shows promising generalization to unseen taxa and tasks. Importantly, we test NatureLM-audio on a novel benchmark (BEANS-Zero) and it sets the new state of the art (SotA) on several bioacoustics tasks, including zero-shot classification of unseen species. To advance bioacoustics research, we also open-source the code for generating training and benchmark data, as well as for training the model.
... Recordings of animal vocalizations are used to study animal communication and animal behavior [4], and to monitor biodiversity [5]. However, such noise presents a large challenge for biologists aiming to evaluate acoustic differences among signals or to automate the measurement of acoustic variables [6]. More, the noise hinders the quality of the generated audio used in playback experiments requiring good quality recordings [1]. ...
Animal vocalization denoising is a task similar to human speech enhancement, a well-studied field of research. In contrast to the latter, it is applied to a higher diversity of sound production mechanisms and recording environments, and this higher diversity is a challenge for existing models. Adding to the challenge and in contrast to speech, we lack large and diverse datasets comprising clean vocalizations. As a solution we use as training data pseudo-clean targets, i.e. pre-denoised vocalizations, and segments of background noise without a vocalization. We propose a train set derived from bioacoustics datasets and repositories representing diverse species, acoustic environments, geographic regions. Additionally, we introduce a non-overlapping benchmark set comprising clean vocalizations from different taxa and noise samples. We show that that denoising models (demucs, CleanUNet) trained on pseudo-clean targets obtained with speech enhancement models achieve competitive results on the benchmarking set. We publish data, code, libraries, and demos https://mariusmiron.com/research/biodenoising.
... The setup of the speakers was in line with recommendations (Fischer et al., 2013): while one researcher was responsible for placing the speaker and playing the sound, one or two other researchers videorecorded the response. In addition, one of the researchers carried the microphone that was used to record Temmy's vocalisations opportunistically. ...
Orang-utans are well-known for their vocal flexibility. However, the described vocal repertoire of female orang-utans is relatively limited. This anecdotal report discusses the occurrence of long call-like vocalisations in two zoo-housed Bornean orang-utan females. While Temmy demonstrated these vocalisations in response to playbacks of male long calls, Eloise proactively produced vocal-isations during her ovulation before her reproductive senescence. The vocalisations produced by Temmy and Eloise seem to differ in many aspects from known orang-utan calls, although they bear some similarities to male long calls. Thus, the vocal repertoire of female orang-utans may be more extensive than previously thought. We carefully suggest that these calls might indicate proceptivity, while also discussing methodological limitations and theoretical considerations.
... Para la grabación de vocalizaciones de mamíferos no voladores, como carnívoros y roedores, entre otros, se puede utilizar un micrófono unidireccional adaptado a un soporte y conectado a una grabadora digital mediante un cable XLR. Dado que la mayoría de registros sonoros de mamíferos no voladores, especialmente primates, permanecen en la parte alta del dosel, se recomienda, al igual que en aves, utilizar un micrófono omnidireccional acoplado a una parábola (Fischer et al., 2013). Este tipo de equipos permiten concentrar y amplificar los sonidos. ...
... Para la grabación de vocalizaciones de mamíferos no voladores, como carnívoros y roedores, entre otros, se puede utilizar un micrófono unidireccional adaptado a un soporte y conectado a una grabadora digital mediante un cable XLR. Dado que la mayoría de registros sonoros de mamíferos no voladores, especialmente primates, permanecen en la parte alta del dosel, se recomienda, al igual que en aves, utilizar un micrófono omnidireccional acoplado a una parábola (Fischer et al., 2013). Este tipo de equipos permiten concentrar y amplificar los sonidos. ...
... The setup of our study was in line with recommendations (Fischer et al., 2013): while one researcher was responsible for placing the speaker and playing the sound, one or two other researchers videorecorded the response. In addition, one of the researchers carried the microphone that was used to record Temmy's vocalisations opportunistically. ...
