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.

No description available.

No description available.

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.

No description available.

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.

Thesis (MSc)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The alarm calls of a colonial rodent, Brants' whistling rat (Parotomys brantsii), were investigated at Goegap Nature Reserve in the Northern Cape, South Africa. At this site P. brantsii occurs in sympatry with the congeneric P. littledalei, and the alarm calls in response to humans was compared between the two species. Parotomys brantsii's typical call in reaction to a human is a simple whistle, characterized by an initial upward frequency sweep and high frequency plateau, whereas the alarm whistle of P. littledalei has three overlapping components. Parotomys littledalei's calls are significantly shorter and lower in dominant frequency than those of P. brantsii, and have a significantly wider frequency bandwidth. These distinctions were attributed to species discrimination and habitat preferences. The acoustic adaptation hypothesis is supported in part, as P. littledalei, which inhabits a closed habitat in comparison with P. brantsii, has calls which are lower in frequency than P. brantsii calls, but contrary to the hypothesis, P. brantsii calls show less frequency modulation than those of P. littledalei. The high pitch of both species' vocalizations may be a convergent feature making the callers difficult for predators to locate. The alarm call repertoire of P. brantsii was investigated by presenting members of the P. brantsii colony with models of some typical predators, a raptor and puff adder, as well as a human observer. Virtually no variation was detected in the structure of alarm whistles elicited by different predators, indicating that P. brantsii did not identify different predator types by means of vocalizations, even though behavioural responses showed that P. brantsii do distinguish between different predators and non-predators. Note duration varied in conjunction with the physical reaction of the caller. When the caller bolted towards safety, the whistle was significantly shorter than when it remained aboveground. During an encounter with a snake or far-off human the caller would utter relatively long duration calls, signifying a low-risk situation, while highrisk situations such as a nearby human or raptor provoked short calls, emitted just before the whistling rat bolted underground. I regard P. brantsii's alarm call repertoire as a graded "urgency-based" system, indicating threat level perceived rather than predator type. This system is widespread among ground squirrels and is usually associated with animals inhabiting a two-dimensional environment. Playback experiments were conducted to determine the meaning of alarm calls to conspecifics, focusing specifically on the effect of variation in single call duration and function of alarm-calling bouts. All alarm calls induced heightened vigilance in receivers, but the behavioural response did not differ between short and long single calls. Multiple calls lead to significantly longer periods of high vigilance than single calls even after calling bouts have ended, showing that one of the functions of multiple calls is to maintain high vigilance in conspecifics for relatively long periods. The non-iconic nature of their alarm calls and the undiscriminating response of receivers to different calls emphasizes the importance of contextual clues in the communication system of animals living in an open habitat like that of P. brantsii. / AFRIKAANSE OPSOMMING: Die alarm-roepgeluide van 'n koloniale knaagdier, Brants se fluitrot (Parotomys brantsii), is ondersoek by Goegap Natuurreservaat in the Noordkaap, Suid-Afrika, waar hulle simpatries voorkom met die naverwante P. littledalei. Die species se alarmroepe in reaksie op mense is met mekaar vergelyk. Die tipiese alarmroep van P. brantsii is 'n eenvoudige fluit, gekenmerk deur 'n aanvanklike skerp frekwensiestyging en hoë-frekwensie plato. Parotomys littledalei se fluitroep het drie komponente wat mekaar gedeeltelike oordek. Parotomys littledalei se roepgeluide is beduidend korter en laer in heersende toonhoogte as dié van P. brantsii, en hul frekwensie-wydte is ook beduidend wyer. Hierdie verskille word toegeskryf aan species-verskille en habitat-voorkeure. Die akoestiese aanpassingshipotese word gedeeltelik deur die studie ondersteun, aangesien P. littledalei, wat 'n geslote habitat verkies in vergelyking met P. brantsii, alarmroepe het met 'n laer dominante toonhoogte as P. brantsii. In teenstelling met die hipotese, toon P. brantsii se fluitgeluide minder frekwensie-modulasie as P. littledalei se geluide. Die hoë toonhoogte van beide species se alarmroepe kan 'n konvergente verskynsel wees wat dit vir roofdiere moeilik maak om fluitende individue te lokaliseer. Die alarm-repertoire van P. brantsii is ondersoek deur individue bloot te stel aan 'n menslike waarnemer en modelle van tipiese predatore, naamlik 'n jakkalsvoël en pofadder. Daar was omtrent geen variasie in die klank-struktuur van alarmroepe in reaksie op verskillende roofdiere nie. Dit wys daarop dat P. brantsii nie roofdiere deur middel van roepgeluide klassifiseer nie, hoewel gedragsresponse getoon het dat individue wel tussen roofdiere kan onderskei. Die duur van alarmroepe varieer na gelang van die gedrag van die fluitende individue - 'n fluitrot wat vlug, se roep is beduidend korter as die geluid van een wat bogronds bly. 'n Pofadder en 'n veraf mens ontlok lankdurende geluide, wat dui op 'n lae-risiko situasie, terwyl rotte op vlug slaan in reaksie op 'n hoë-risiko situasie, soos met 'n nabygeleë mens of jakkalsvoël, wanneer kort alarmroepe geuiter word. Ek beskou P. brantsii se alarmrepertoire as 'n gegradeerde "nood-gebaseerde" stelsel, wat die mate van bedreiging aandui, eerder as die identiteit van die spesifieke roofdier. Hierdie sisteem is tipies van grondeekhorings en word gewoonlik verbind met diere wat 'n twee-dimensionele omgewing bewoon. Parotomys brantsii se reaksie op die terugspeel van die species se geluide is hierna ondersoek. Ek het gefokus op die effek van 'n verandering in die duur van alleenstaande fluitnote, asook hulle reaksie op fluitreekse. Alle alarmroepe het gelei tot hoër vlakke van waaksaamheid in luisterende individue, maar reaksies op kort en lang enkelnote het nie van mekaar verskil nie. Fluitreekse het beduidend langer periodes van hoë waaksaamheid veroorsaak as enkele geluide, en waaksaamheid het hoog gebly selfs nadat reekse geëindig het. Dit beteken dat fluitreekse onder andere die funksie vervul om waaksaamheid in kolonielede vir relatief lang tye te onderhou. Parotomys brantsii se eenvoudige alarm-repertoire en nie-onderskeidende reaksie op verskillene roepgeluide, beklemtoon die belangrikheid van aanvullende inligting uit die omgewing vir diere in 'n twee-dimensionele habitat wanneer die akoestiese kommunikasiestelse slegs 'n algemene waarskuwingsfunksie vervul.

Geographic variation in the whistle vocalisations of dolphins has previously been reported. However, most studies have focused on the whole whistle repertoire, with little attempt to classify sounds into biologically relevant categories. Common bottlenose dolphins (Tursiops truncatus) use individually distinctive signature whistles which are thought to help maintain contact between conspecifics at sea. These whistles may show a different kind of variation between populations than non-signature whistles. Here I investigate signature whistle use and variation in the two recognised species of bottlenose dolphins (T. truncatus and T. aduncus) from populations inhabiting the coastal waters of the North America, Scotland, South Africa, Tanzania, Japan, Australia and New Zealand, and one captive colony. I identified likely signature whistles (signature whistles types, SWTs) from acoustic recordings by combining two novel techniques: automated contour categorisation in ARTwarp (Deecke and Janik, 2006) and a specific bout analysis based on the timing of signature whistle production in T. truncatus termed SIGID (Janik et al. in press). Three ways of categorising the contours were tested and between 87 and 111 SWTs were identified in total. Repeated emissions of stereotyped contours were apparent in the repertoire of all T. aduncus populations using both automated and human observer categorisation, providing good evidence for signature whistle use in this species. There was significant inter-specific variation in the frequency parameters, looping patterns and duration of SWTs. Inflection points, duration and measures of SWT complexity showed high variation within populations, suggesting inter- and intra-individual modification of these parameters, perhaps to enhance identity encoding or convey motivational information. Using 328 bases of the mtDNA control region, I found high levels of population differentiation (FST and φST) within the genus Tursiops. These data do not support a link between mtDNA population differentiation and variability in call type. Instead, morphological variations at the species level, and learned differences at the population level, better explain the variation found.