Killer whales are capable of vocal learning

The production learning of vocalizations by manipulation of the sound production organs to alter the physical structure of sound has been demonstrated in only a few mammals. In this natural experiment, we document the vocal behaviour of two juvenile killer whales, Orcinus orca , separated from their natal pods, which are the only cases of dispersal seen during the three decades of observation of their populations. We find mimicry of California sea lion ( Zalophus californianus ) barks, demonstrating the vocal production learning ability for one of the calves. We also find differences in call usage (compared to the natal pod) that may reflect the absence of a repertoire model from tutors or some unknown effect related to isolation or context.

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Morphological facilitators for vocal learning explored through the syrinx anatomy of a basal hummingbird

10.1101/2020.01.11.902734 ◽

2020 ◽

Cited By ~ 1

Author(s):

Amanda Monte ◽

Alexander F. Cerwenka ◽

Bernhard Ruthensteiner ◽

Manfred Gahr ◽

Daniel N. Düring

Keyword(s):

Sound Production ◽

Three Dimensional ◽

Vocal Learning ◽

Dimensional Structure ◽

Micro Computed Tomography ◽

Vocal Production ◽

Precise Control ◽

Acoustic Space ◽

Biomechanical Factors ◽

Intrinsic Musculature

AbstractVocal learning is a rare evolutionary trait that evolved independently in three avian clades: songbirds, parrots, and hummingbirds. Although the anatomy and mechanisms of sound production in songbirds are well understood, little is known about the hummingbird’s vocal anatomy. We use high-resolution micro-computed tomography (μCT) and microdissection to reveal the three-dimensional structure of the syrinx, the vocal organ of the black jacobin (Florisuga fusca), a phylogenetically basal hummingbird species. We identify three unique features of the black jacobin’s syrinx: (i) a shift in the position of the syrinx to the outside of the thoracic cavity and the related loss of the sterno-tracheal muscle, (ii) complex intrinsic musculature, oriented dorso-ventrally, and (iii) ossicles embedded in the medial vibratory membranes. Their syrinx morphology allows vibratory decoupling, precise control of complex acoustic parameters, and a large redundant acoustic space that may be key biomechanical factors facilitating the occurrence of vocal production learning.

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A Call to Expand Avian Vocal Development Research

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.757972 ◽

2021 ◽

Vol 9 ◽

Author(s):

Yen Yi Loo ◽

Kristal E. Cain

Keyword(s):

Life Histories ◽

Continuum Hypothesis ◽

Vocal Learning ◽

Neural Substrates ◽

Learning Ability ◽

Development Studies ◽

Vocal Development ◽

Vocal Production ◽

Development Patterns ◽

Vocal Control

Birds are our best models to understand vocal learning – a vocal production ability guided by auditory feedback, which includes human language. Among all vocal learners, songbirds have the most diverse life histories, and some aspects of their vocal learning ability are well-known, such as the neural substrates and vocal control centers, through vocal development studies. Currently, species are classified as either vocal learners or non-learners, and a key difference between the two is the development period, extended in learners, but short in non-learners. But this clear dichotomy has been challenged by the vocal learning continuum hypothesis. One way to address this challenge is to examine both learners and canonical non-learners and determine whether their vocal development is dichotomous or falls along a continuum. However, when we examined the existing empirical data we found that surprisingly few species have their vocal development periods documented. Furthermore, we identified multiple biases within previous vocal development studies in birds, including an extremely narrow focus on (1) a few model species, (2) oscines, (3) males, and (4) songs. Consequently, these biases may have led to an incomplete and possibly erroneous conclusions regarding the nature of the relationships between vocal development patterns and vocal learning ability. Diversifying vocal development studies to include a broader range of taxa is urgently needed to advance the field of vocal learning and examine how vocal development patterns might inform our understanding of vocal learning.

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A researcher's guide to the comparative assessment of vocal production learning

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2020.0237 ◽

2021 ◽

Vol 376 (1836) ◽

pp. 20200237

Author(s):

Ella Z. Lattenkamp ◽

Stephen G. Hörpel ◽

Janine Mengede ◽

Uwe Firzlaff

Keyword(s):

Sound Production ◽

Production Systems ◽

Experimental Studies ◽

Vocal Learning ◽

Comparative Assessment ◽

Theme Issue ◽

Acoustic Parameters ◽

Animal Kingdom ◽

Vocal Production ◽

Five Factors

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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Supplemental Material for Personality Dimensions of the Captive California Sea Lion (Zalophus californianus)

Journal of Comparative Psychology ◽

10.1037/com0000054.supp ◽

2017 ◽

Keyword(s):

Zalophus Californianus ◽

Sea Lion ◽

California Sea Lion ◽

Personality Dimensions

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Visual Learning set in a California sea lion

PsycEXTRA Dataset ◽

10.1037/e598092013-099 ◽

2011 ◽

Author(s):

Molly McCormley ◽

Peter Cook ◽

Madison Miketa ◽

Colleen Reichmuth

Keyword(s):

Visual Learning ◽

Sea Lion ◽

California Sea Lion ◽

Learning Set

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Rehabilitation and Movement of a Blind California Sea Lion from the Southern Gulf of California to the Western Baja California Peninsula, Mexico

Aquatic Mammals ◽

10.1578/am.44.3.2018.293 ◽

2018 ◽

Vol 44 (3) ◽

pp. 293-298

Author(s):

Fernando R. Elorriaga-Verplancken ◽

Patricia Meneses ◽

Abraham Cárdenas-Llerenas ◽

Wayne Phillips ◽

Abel de la Torre ◽

...

Keyword(s):

Gulf Of California ◽

Baja California ◽

Baja California Peninsula ◽

Sea Lion ◽

California Sea Lion

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Vocal Creativity in Elephant Sound Production

Biology ◽

10.3390/biology10080750 ◽

2021 ◽

Vol 10 (8) ◽

pp. 750

Author(s):

Angela S. Stoeger ◽

Anton Baotic ◽

Gunnar Heilmann

Keyword(s):

Cognitive Abilities ◽

Positive Reinforcement ◽

Sound Production ◽

Vocal Learning ◽

Learning Processes ◽

Fine Tuning ◽

Social Feedback ◽

Nasal Tissue ◽

Production Techniques ◽

Production Mechanisms

How do elephants achieve their enormous vocal flexibility when communicating, imitating or creating idiosyncratic sounds? The mechanisms that underpin this trait combine motoric abilities with vocal learning processes. We demonstrate the unusual production techniques used by five African savanna elephants to create idiosyncratic sounds, which they learn to produce on cue by positive reinforcement training. The elephants generate these sounds by applying nasal tissue vibration via an ingressive airflow at the trunk tip, or by contracting defined superficial muscles at the trunk base. While the production mechanisms of the individuals performing the same sound categories are similar, they do vary in fine-tuning, revealing that each individual has its own specific sound-producing strategy. This plasticity reflects the creative and cognitive abilities associated with ‘vocal’ learning processes. The fact that these sounds were reinforced and cue-stimulated suggests that social feedback and positive reinforcement can facilitate vocal creativity and vocal learning behavior in elephants. Revealing the mechanism and the capacity for vocal learning and sound creativity is fundamental to understanding the eloquence within the elephants’ communication system. This also helps to understand the evolution of human language and of open-ended vocal systems, which build upon similar cognitive processes.

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Adding colour-realistic video images to audio playbacks increases stimulus engagement but does not enhance vocal learning in zebra finches

Animal Cognition ◽

10.1007/s10071-021-01547-8 ◽

2021 ◽

Author(s):

Judith M. Varkevisser ◽

Ralph Simon ◽

Ezequiel Mendoza ◽

Martin How ◽

Idse van Hijlkema ◽

...

Keyword(s):

Visual Cues ◽

Sound Production ◽

Visual Stimuli ◽

Vocal Learning ◽

Song Learning ◽

Frame Rate ◽

Zebra Finches ◽

Video Content ◽

Biologically Relevant ◽

Video Images

AbstractBird song and human speech are learned early in life and for both cases engagement with live social tutors generally leads to better learning outcomes than passive audio-only exposure. Real-world tutor–tutee relations are normally not uni- but multimodal and observations suggest that visual cues related to sound production might enhance vocal learning. We tested this hypothesis by pairing appropriate, colour-realistic, high frame-rate videos of a singing adult male zebra finch tutor with song playbacks and presenting these stimuli to juvenile zebra finches (Taeniopygia guttata). Juveniles exposed to song playbacks combined with video presentation of a singing bird approached the stimulus more often and spent more time close to it than juveniles exposed to audio playback only or audio playback combined with pixelated and time-reversed videos. However, higher engagement with the realistic audio–visual stimuli was not predictive of better song learning. Thus, although multimodality increased stimulus engagement and biologically relevant video content was more salient than colour and movement equivalent videos, the higher engagement with the realistic audio–visual stimuli did not lead to enhanced vocal learning. Whether the lack of three-dimensionality of a video tutor and/or the lack of meaningful social interaction make them less suitable for facilitating song learning than audio–visual exposure to a live tutor remains to be tested.

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