The significance of vocal communication in subterranean rodents was confirmed. In this study I tested whether vocalization of the Mashona mole-rats (Fukomys darlingi) differs individually and what information about signaller are these mole-rats able to obtain using only acoustic cues.

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Mutual parent-young recognition is vital for offspring survival, particularly in species congregating in dense breeding sites, like pinnipeds (seals, sea lions, and walruses). For effective vocal recognition, the caller must produce individually specific calls with high levels of stereotypy, or individuality. Vocal recognition has been studied extensively and is well-documented in otariid species (fur seals and sea lions), as those mothers frequently leave their pup to forage and must relocate them upon return to the rookery. In many phocid (true seal) species, the mothers typically remain with their pup throughout nursing and therefore may not have as strong of a need for well-developed vocal recognition; recognition remains understudied in these species. This study focuses on vocal recognition and individuality in the northern elephant seal (Mirounga angustirostris), a phocid species with a 28-day nursing period and no intentional separation between mothers and pups. In Chapter 1, I investigated a northern elephant seal pup’s ability to vocally recognize its mother across ontogeny through an auditory playback experiment at the Piedras Blancas northern elephant seal rookery in San Simeon, CA. I found that pups showed a developed ability to recognize their mother’s vocalizations later in the nursing period, at around 23 days old. At this age, they looked towards their mother’s call faster and spent more time investigating the call. Before this age, pups responded infrequently to female vocalizations and showed no differentiated response to their own mother versus an unfamiliar female. After weaning, pups responded to any female’s call. This study is the first to examine phocid pup vocal recognition abilities, and the results suggest that northern elephant seal mothers are primarily responsible for maintaining contact during the nursing period to ensure their pup’s survival. In Chapter 2, I analyzed and described the pup attraction calls made by adult females. Visual and auditory analysis of the spectrograms suggested there may be distinct variants of attraction calls made within and across females. I characterized the calls and confirmed that female elephant seals produce three distinct variants of their attraction call. A linear discriminant analysis correctly classified the calls into their assigned categories 80% of the time. Previous research found that female elephant seals have lower vocal stereotypy than female northern fur seals. Because I demonstrated that female elephant seals produce different variants of attraction calls, I reevaluated their stereotypy while controlling for the attraction call variant. I found that female elephant seals have a higher level of stereotypy when controlling for call variant, with a linear discriminant analysis correctly assigning 50% of the calls to the correct female when controlling for call variant, and correctly assigning 37.5% of the calls when not controlling for call variant. In summary, my results suggest that mother-pup recognition is mutual in northern elephant seals, but indicate that northern elephant seal mothers are primarily responsible for maintaining contact with their pup during dependency, as the pups do not consistently respond to their mothers’ vocalizations until the last week of the nursing period. Adult females produce calls with enough vocal stereotypy to allow for individual recognition, and they make distinct variants of attraction calls, indicating they have a larger vocal repertoire than previously assumed. Future research should further investigate adult female northern elephant seal vocalizations and how they potentially differ across ontogeny and among behavioral contexts.

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The morning duet calls of eastern tarsiers (Tarsius spp.) in North Sulawesi were recorded and analyzed to examine the effects of geography and geologic history on their call structure. Tarsius species exhibit interspecifically variable duet calls shown to correlate with species differentiation and distribution. They are distributed across Sulawesi, a biogeographically complex island in the Indonesian archipelago, where tectonic activity and multiple glaciations during the Pleistocene generated and modified barriers to their dispersal and gene flow. Recordings were made at ten locations from November of 2012 through June of 2014. Two locations were categorized as mainland, while eight island locations were categorized as either shallow or deep, according to the distance and bathymetric depth separating them from the mainland. The first hypothesis was that tarsier calls on islands separated by depths of less than 130 meters would be more strongly correlated to calls found on the mainland than would the calls from islands separated by deeper water, due to dispersal and possible hybridizations during glaciations. There was a higher degree of similarity between the mainland locations and the shallow water islands than was found between the deep water islands and either shallow water islands or the mainland. The second hypothesis was that a stepping stone pattern of colonization would be evidenced in the acoustic structure of tarsiers from the Sangihe Arc, with each island showing vocalizations more similar to its immediate neighbors than to other islands. Since tarsiers were not found to be present on two of the islands, it was not possible to trace the entire arc as planned. It was found, however, that Sangihe (the largest island and the farthest north of the islands) was the most acoustically unique, as expected. Both genetic drift and environmental factors play a role in evolving animal communication, but I hypothesize that it is more likely the former at work in this case, as the habitats are similar, and I found no strong evidence of short term habitat adaptations or frequency partitioning. The spectral and temporal structure of the duet calls on the mainland and shallow water islands showed no clear geographical bias or patterns, suggesting that panmixia and hybridization during recurring glaciations may function in preventing subdivisions among the populations.

Adult rats produce two main types of ultrasonic vocalizations (USVs), occurring at 22 and 50 kHz USVs. These calls are associated with aversive and rewarding stimuli, respectively. The neural mechanism of amphetamine-induced calling was examined in lesion and antagonist studies. We also tested whether amphetamine-induced 50 kHz USVs could predict individual differences in intravenous self-administration or conditioned place preference behavior. Further experiments examined whether 50 kHz USVs could be evoked by amphetamine-conditioned sensory stimuli and by rewarding electrical brain stimulation. Overall, our experimental findings: (1) identify certain experimental conditions that increase amphetamine-induced 50 kHz calling, (2) provide evidence that these calls may be dependent on mesolimbic dopaminergic transmission, (3) relate individual differences in 50 kHz vocalizing to other behavioural measures of drug reward, and (4) show that in some situations, 50 kHz calls reflect anticipation of expected rewards.

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This study compared male response to playback and interspecific vocal imitation in two White-eyed Vireo populations, in southwestern Virginia and eastern North Carolina. White-eyed Vireos are hypothesized to imitate notes from other birds which transmit efficiently through dense habitat. Male White-eyed Vireos did not respond differently to playback of each other I s songs. The song repertoires between Virginia and North Carolina were not found to include strikingly different imitations despite the different sound environments. Degradation and attenuation of White-eyed Vireo song notes was also compared between the two locations. There was no statistically significant difference in degradation or attenuation of notes when compared to native or foreign habitat. Notes occurring more frequently in the population did not transmit more efficiently. Notes unique to North Carolina did transmit more efficiently in their native habitat, but this difference was explained by the relatively less dense habitat in North Carolina. / Master of Science

Made available in DSpace on 2016-12-08T16:51:59Z (GMT). No. of bitstreams: 1 114037.pdf: 2441864 bytes, checksum: b9e78a3d20e9a224a0d901ebb9cb39e0 (MD5) Previous issue date: 2013-09-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research focuses on the voice in Puppet Theater a term that embraces different kinds of performances, characterized by hybridity and the dynamics of the animate/inanimate present in Puppet Theater, Mask Theater, Shadow Puppetry, Visual Theater, etc. The voice is approached, in Puppet Theater, as a creator of presence and meaning, according to Hans Ulrich Gumbrecht s theory of presence production. I investigate how the voice can generate presence in relation to specific Puppet Theater poetics. The voice, in singular, refers to its essence as an oscillation between presence and meaning. However, since the voice unfolds itself in different cultural, poetic and historical contexts, actually the voice is plural in its several manifestations. By setting out the following problem, when voice is in Puppet Theater? , I seek to identify poetics that are also defined by its voice presence. Once identified such poetics, I seek to distinguish the voice s generating and constituting elements that establish it as presence and meaning, in relation to its poetics. During the investigation, I contemplate authors and artists that reflect about the use of voice in Puppet Theater and research their procedures, as well as those who treat it as a background to or even outlaw it from the scene. I survey the bibliography on the subject, bring examples from national and international performances seen in the last three years in Brazil, and use material drawn from interviews, seminars and courses realized in this period. Along this research, some recurring vocal procedures in Puppet Theater are individuated, and in some cases, these revealed themselves as specific to an art form characterized by the separation between the puppet-object and its sound source. During the investigation I came to realize that, although the Brazilian Puppet Theater quite often uses speech in its performances, there is significant absence of voice as I have defined above: voice as an oscillation between presence and meaning. Based on Adriana Cavarero s philosophical studies, which describe the de- vocalization process of a civilization centered in the logos (understood as reason), I realized that this process is mirrored by the Puppet Theater scene. The twentieth century emerges as a century in which performances are based on the sense of vision, promoted by a civilization centered on the image. The sense of vision has taken over all the other senses, promoting the de-vocalization of the logos, leading to a de-vocalization of the scene. The aim with this research is to - identify the vocal havens and to investigate the procedures that establish this oscillation between presence and meaning in Puppet Theater s voice, in relation to its poetics. This purpose is key to the re-vocalization in contemporary Brazilian Puppet Theater. / Esta pesquisa trata a voz no Teatro de Animação - termo que abraça diversas formas espetaculares híbridas centradas na dinâmica do animado/inanimado, como o teatro de bonecos, de máscaras, de sombras, visual, etc. A voz é abordada, no Teatro de Animação, como produtora de presença e sentido, conforme a teoria de produção de presença de Hans Ulrich Gumbrecht. Investigo como a voz gera presença numa relação com determinada poética no âmbito do Teatro de Animação. A voz no singular refere-se à sua essência como oscilação entre presença e sentido. Todavia, como a voz surge em diferentes contextos culturais e poéticos, ou seja, históricos, a voz na realidade é plural nas suas diversas manifestações. A partir da questão quando a voz é no Teatro de Animação? , procuro identificar poéticas que engendram o princípio pelo qual a voz é. Uma vez identificada a poética, busco distinguir os elementos que geram e constituem a voz, instaurando-a como presença e sentido, numa relação com a sua poética. Na investigação, contemplo autores e artistas que refletem sobre o uso da voz no teatro de animação e exploram seus procedimentos, assim como aqueles que a relegam a segundo plano ou mesmo a banem da cena. Faço um levantamento bibliográfico do assunto, recorro a exemplos de espetáculos nacionais e internacionais assistidos nos últimos três anos no Brasil e utilizo material colhido em entrevistas, seminários e cursos realizados nesse período. Durante a exposição desta pesquisa são individuados procedimentos recorrentes de uso da voz no Teatro de Animação que, em alguns casos, revelaram-se como específicos da linguagem cuja característica é a separação entre boneco-objeto e fonte sonora. Durante a investigação, constato que, embora a voz seja muito utilizada em cena no Teatro de Animação no Brasil, há uma significante ausência da voz como a defino acima: voz como oscilação entre presença e sentido. A partir dos estudos filosóficos de Adriana Cavarero, que descreve um processo de desvocalização numa civilização centrada no logos entendido como razão, chego à conclusão de que esse processo se espelha na cena do teatro de animação. O século XX desponta como um século cuja espetacularidade teatral é calcada na visão, reflexo de uma civilização centrada na imagem, em que o sentido da visão tem primazia sobre os outros sentidos, promovendo a desvocalização do logos, levando a uma desvocalização na cena. Tal conclusão faz com que o propósito da pesquisa - identificação dos redutos vocais e investigação dos procedimentos que instauram uma oscilação de presença e sentido na voz no Teatro de Animação, numa relação com as poéticas - seja fundamental para a revocalização da cena no Teatro de Animação contemporâneo no Brasil.