Relatively little is known about the vocal repertoire of Asian elephants (Elephas maximus), and a categorization of basic call types and modifications of these call types by quantitative acoustic parameters is needed to examine acoustic variability within and among call types, to examine individuality, to determine communicative function of calls via playback, to compare species and populations, and to develop rigorous call recognition algorithms for monitoring populations. This study defines an acoustic repertoire of Asian elephants based on acoustic parameters, compares repertoire usage among groups and individuals, and validates structural distinction among call types through comparison of manual and automated classification methods. Recordings were made of captive elephants at the Oregon Zoo in Portland, OR, USA, and of domesticated elephants in Thailand. Acoustic and behavioral data were collected in a variety of social contexts and environmental noise conditions. Calls were classified using perceptual aural cues plus visual inspection of spectrograms, then acoustic features were measured, then automated classification was run. The final repertoire was defined by six basic call types (Bark, Roar, Rumble, Bark, Squeal, Squeal, and Trumpet), five call combinations and modifications with these basic calls forming their constituent parts (Roar-Rumble, Squeal-Squeak, Squeak train, Squeak-Bark, and Trumpet-Roar), and the Blow. Given the consistency of classifications results for calls from geographically and socially disparate subject groups, it seems possible that automated call detection algorithms could be developed for acoustic monitoring of Asian elephants.

Vocalisations of the endangered Brown Kiwi (Apteryx mantelli) are currently used in a nationwide monitoring program to assess the health of a number of small remnant populations. Only an estimate of population health can be obtained from these surveys. This has to form the basis for a number of critical management decisions. The ability to identify kiwi individually during monitoring would greatly improve the accuracy and quality of information obtained and provide a wider base of knowledge when management decisions are made. This study produces a detailed description of the male and female kiwi call, including duetting and seasonal variations. It then explores whether kiwi demonstrate individually distinctive vocalisations, which could be used in conservation management of kiwi.Calls from seven male and four female kiwi were recorded from Rarewarewa, Whangarei between the 5th of May 2003 to the 31st of April 2004. Two call variables (call duration, number of syllables), two temporal syllable variables (syllable duration, syllable gap duration) and five syllable spectral variables (frequency with the most amplitude, high frequency, low frequency, start frequency, end frequency) were measured from 48 male and 14 female calls. Variables from each call were used to describe and classify calls using one way repeated measures ANOVAs and Discriminant Function Analysis. Males contained on average 24 syllables and females containing on average 22 syllables, with calls from both sexes lasting on average 28 seconds. Male and female kiwi calls differed in multiple spectral, temporal and structural features. Dueting rates and behaviour differed between pairs. Some pairs almost always called in duets, whereas others never dueted. Dueting behaviour also changed seasonally with fewer duets occurring in the non-breeding season and with females initiating more duets in the breeding season. Call structure did not differ between the breeding and non-breeding season. Although the sample size was not sufficient to test for this.Statistically significant differences occurred among nearly all variables between individual male and female kiwi calls, despite statistically significant difference occurring between syllables within calls. Frequency variables were the most important variables in discriminating between individuals, but multiple spectral and temporal variables were needed to separate all individuals. Discriminant Function Analysis was able to correctly classify 87.5% of male and 85.7% of female calls correctly when using the means of the seven syllable variables and the two call variables and 68.2% of male and 66.8% when using the values from each syllable. The latter was improved to 85.9% of male calls correctly classified when only 3 syllables from the middle of the calls were used in DFA, reflecting the variation found at the beginning and end of calls.Brown kiwi show strong signs of individually distinctive vocalisations, which remained consistent over a one year period. The conservation implications of individually distinctive vocalisations and how this feature could be incorporated into the current monitoring of kiwi are discussed.

<p>Bird incubation is a natural phenomenon that balances the needs of the parents for nourishment with the needs of the fetus for heat provision and protection. In this context, any means of communication between the fetus and the parents would have an adaptive value. The aim of the study was to investigate whether putative means of fetomaternal communication would correlate to physiological changes caused by environmental alterations. Oxygen consumption was used to measure fetal well being and six independent variables associated with fetal vocalizations and fetal movements were used to evaluate their potential for communicating the fetus statu quo. Broiler fetuses (<em>Gallus gallus domesticus</em>) of three developmental stages (day 18, internally pipped and externally pipped) were challenged by a stepwise reduction in ambient temperature down to 30ºC. A linear drop in oxygen consumption in response to lowered temperatures was found in all three developmental stages indicating that the fetus was affected by the temperature changes. No differences correlating with temperature variations were found in any of the variables associated with fetal vocalization. Fetal vocalizations are consequently not used to communicate the thermal status of the fetus. Movement occurrence, movement intensity and ventilation frequency, however, followed a “maximum peak” trend, with a highest response at the third temperature interval (35.0-35.5ºC). Considering that the lower limit of optimal development is between 35-36ºC, the results suggest that fetal movements can be of potential use to the incubating parent to assess the well-being of the fetus.</p>

Bird incubation is a natural phenomenon that balances the needs of the parents for nourishment with the needs of the fetus for heat provision and protection. In this context, any means of communication between the fetus and the parents would have an adaptive value. The aim of the study was to investigate whether putative means of fetomaternal communication would correlate to physiological changes caused by environmental alterations. Oxygen consumption was used to measure fetal well being and six independent variables associated with fetal vocalizations and fetal movements were used to evaluate their potential for communicating the fetus statu quo. Broiler fetuses (Gallus gallus domesticus) of three developmental stages (day 18, internally pipped and externally pipped) were challenged by a stepwise reduction in ambient temperature down to 30ºC. A linear drop in oxygen consumption in response to lowered temperatures was found in all three developmental stages indicating that the fetus was affected by the temperature changes. No differences correlating with temperature variations were found in any of the variables associated with fetal vocalization. Fetal vocalizations are consequently not used to communicate the thermal status of the fetus. Movement occurrence, movement intensity and ventilation frequency, however, followed a “maximum peak” trend, with a highest response at the third temperature interval (35.0-35.5ºC). Considering that the lower limit of optimal development is between 35-36ºC, the results suggest that fetal movements can be of potential use to the incubating parent to assess the well-being of the fetus.

<p>Mice produce many ultrasonic vocalizations (USVs) in the 30 - 100 kHz range including pup isolation calls and adult male songs. These USVs are often used as behavioral readouts of internal states, to measure effects of social and pharmacological manipulations, and for behavioral phenotyping of mouse models for neuropsychiatric and neurodegenerative disorders; however, little is known about the biophysical and neurophysiological mechanisms of USV production in rodents. This lack of knowledge restricts the interpretation of data from vocalization-related experiments on mouse models of communication disorders and vocal medical conditions. Meanwhile, there has been increased interest in the social communication aspect of neural disorders such as autism, in addition to the common disorders involving motor control of the larynx: stroke, Parkinson's disease, laryngeal tremor, and spasmodic dysphonia. Therefore, it is timely and critical to begin assessing the neural substrate of vocal production in order to better understand the neuro-laryngeal deficits underlying communication problems.</p><p>Additionally, mouse models may generate new insight into the molecular basis of vocal learning. Traditionally, songbirds have been used as a model for speech learning in humans; however, the model is strongly limited by a lack of techniques for manipulating avian genetics. Accordingly, there has long been strong interest in finding a mammalian model for vocal learning studies. The characteristic features of accepted vocal learning species include programming of phonation by forebrain motor areas, a direct cortical projection to brainstem vocal motoneurons, and dependence on auditory feedback to develop and maintain vocalizations. Unfortunately, these features have not been observed in non-human primates or in birds that do not learn songs. Thus, in addition to elucidating vocal brain pathways it is also critical to determine the extent of any vocal learning capabilities present in the mouse USV system.</p><p>It is generally assumed that mice lack a forebrain system for vocal modification and that their USVs are innate; however, these basic assumptions have not been experimentally tested. I investigated the mouse song system to determine if male mouse song behavior and the supporting brain circuits resemble those of known vocal learning species. By visualizing activity-dependent immediate early gene expression as a marker of global activity patterns, I discovered that the song system includes motor cortex and striatal regions active during singing. Retrograde and anterograde tracing with pseudorabies virus and biodextran amines, respectively, revealed that the motor cortical region projects directly to the brainstem phonatory motor nucleus ambiguus. Chemical lesions in this region showed that it is not critical for producing innate templates of song syllables, but is required for producing more stereotyped acoustic features of syllables. To test for the basic components of adaptive learning I recorded the songs of mechanically and genetically deaf mice and found that male mice depend on auditory feedback to develop and maintain normal ultrasonic songs. Moreover, male mice that display natural strain specific song features may use auditory experience to copy the pitch of another strain when housed together and stimulated to compete sexually. I conclude that male mice have neuroanatomical and behavioral features thought to be unique to humans and song learning birds, suggesting that mice are capable of adaptive modification of the spectral features of their songs.</p> / Dissertation

Vocal plasticity is presumed to be a key element underlying the evolution of human speech and language, but the mechanisms and neuroanatomical basis for this plasticity remain largely unknown. The Mexican free-tailed bat, Tadarida brasiliensis, presents a unique opportunity to advance our understanding of the evolution and neurobiology of mammalian vocal communication because this animal displays elements of vocal complexity and plasticity that are more sophisticated than any mammal other than humans, including non-human primates. Current models of vocal control in mammals do not account for the vocal complexity of free-tailed bats. The purpose of this dissertation is to fill that gap in knowledge by identifying a possible neuronal basis for vocal complexity in free-tailed bats. This will be achieved by 1) providing a detailed analysis of the free-tailed bat’s vocal behaviors, 2) mapping the distribution of neurotransmitter receptor types suspected of involvement in vocal control, 3) identifying brain regions that exhibit increased neuronal activity during vocalizing, and 4) pharmacologically manipulating putative vocal control regions to confirm and characterize their function in vocalizing. Analysis of Tadarida’s vocal behavior indicated that they have a vast vocal repertoire, including many different call types, context-dependent sensory-feedback driven vocal plasticity, and syntactically-organized stereotyped songs. Their vocal behavior changed seasonally, so I mapped the distribution of melatonin binding sites in the brain, finding high densities in the striatum, similar to dopamine receptor distribution. I then used immunohistochemical labeling of the immediate early gene cfos to map neuronal activation in brains of highly vocal bats to find ROIs activated by vocal production. This technique not only identified all previously known regions of the mammalian vocal motor pathway but also revealed activity in novel brain regions that could potentially account for vocal plasticity, including a localized region of the basal ganglia, the dorsolateral caudate nucleus, and the anterior cingulate region of the frontal cortex. Pharmacological excitation of these regions evoked complex vocal sequences similar to the songs recorded in the field and lab. These results support the hypothesis that the mammalian basal ganglia may play a crucial role in the plasticity and complexity of mammalian vocal behaviors.

Hypothesized functions of complex song in birds include a role in mate attraction and territory defense and, through regional dialects, in genetic substructuring of populations and speciation. The necessary first step in testing such functions is a detailed characterization of song organization and variability. This is provided for the Northern House Wren (Troglodytes aedon), a species noted for complex song, but lacking detailed descriptions. The species was studied at two sites in Alberta with a sample of 15,000 songs from 15 males. Males sang in long bouts, each song composed of multiple syllable types and repeated many times before switching. The population repertoire of 27 syllables was almost entirely shared, but used to construct novel repertoires of up to 200 different song types for individual males without evidence of a ceiling. Additional flexibility and constraints in song construction are discussed in view of the above noted functions of song complexity. / x, 111 leaves : ill., maps ; 29 cm

This work provides an initial characterization of song sharing among males in the Northern House Wren (Troglodytes aedon parkmanii). A sample of 21 different males was studied at two different locations across two breeding seasons in southern Alberta, Canada. In total, 35,067 songs were analyzed to assess patterns of song sharing among males within and between study sites and in returning males between years. Virtually all syllable types (n=27) were shared among males. However, they were used to create very large repertoires of mostly unique song types. Absolute levels of song sharing among males was low but song sharing was higher among neighbouring males and decreased with increasing distance between males and across study sites. These patterns are discussed as they relate to important issues in the process of song learning, in the functions of large song repertoires in mate attraction and territory defense, and in the potential formation of dialects in this species. / xi, 102 leaves ; 29 cm

Thesis (Ph. D.)--University of Wisconsin-Madison, 1999. / Typescript. Includes bibliographical references.

Dogs are well adapted to a life close to humans and are capable of understanding several human social cues. Turn-taking is a fundamental phenomenon in human conversations, yet no research of turn-taking in interspecies vocal communication has been done. This pilot study therefore aimed to develop a test method in order to analyze if turn-taking occurs in interspecies vocal communication between dogs and humans and if turn-taking can be correlated with specific behaviors in dogs. By analyzing a vocal conversation between seven dogs and their owners during a request situation in their home environment, this study found support for turn-taking existence in dog-human vocal communications. In general, owner-dog vocal communication could be linked to positive events, such as tail wagging and eye contact. Meanwhile, a lower frequency of vocal turn- taking could be linked to stress related behaviors, such as lip licking. Owner in dyads where more vocal overlap occurred tended to score the owner-dog relationship and communication abilities with lower grades, suggesting the absence of turn-taking was experienced as unpleasant for the owner as well. In conclusion, findings from current study highlight the unique coevolution of dogs and humans and opens up for future research of turn-taking in interspecies vocal communication.