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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Hesitação e ousadia na tilápia-do-Nilo: identificação, comunicação intraespecífica e papel social

Silva, Graziela Valença da [UNESP] 28 February 2014 (has links) (PDF)
Made available in DSpace on 2015-01-26T13:21:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-28Bitstream added on 2015-01-26T13:30:19Z : No. of bitstreams: 1 000799154_20160228.pdf: 52202 bytes, checksum: 76fa6134f11454fb1ba0ba875b062bce (MD5) Bitstreams deleted on 2016-02-29T12:16:19Z: 000799154_20160228.pdf,. Added 1 bitstream(s) on 2016-02-29T12:17:21Z : No. of bitstreams: 1 000799154.pdf: 395350 bytes, checksum: bd21d099fbf7cf38b3efaf6c731151ee (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Avaliamos a associação entre o escurecimento do olho e a hesitação na tilápia-do-Nilo, Oreochromis niloticus. Para isso, mensuramos a porcentagem de escurecimento da esclera (cor do olho basal) de 48 peixes, que estavam isolados por 4 dias. Em seguida, avaliamos a hesitação e ousadia por meio do teste do objeto novo. Após 24 h, mensuramos novamente a cor do olho (cor pré-hipóxia) e submetemos o peixe a estressor (hipóxia: 2 min fora d’água), registrando a cor do olho imediatamente após esse estressor (cor pós-hipóxia). Ao retornarem ao aquário, avaliamos o tempo para o olho retornar à cor pré-hipóxia. O tempo despendido na exploração do objeto variou de 0 a 570 s. Desses dados, identificamos peixes hesitantes (1º quartil: Q1=0 a 10 s) e ousados (3º quartil: Q3=231 a 570 s). Os hesitantes tinham o olho mais escuro antes do teste do objeto novo (cor basal) e antes do estressor (pré-hipóxia). Com a hipóxia, todos os peixes escureceram o olho, mas o retorno à cor pré-hipóxia demorou mais nos hesitantes. O sexo não interferiu nessas respostas. Concluímos que o escurecimento do olho está associado à hesitação na tilápia-do-Nilo, o qual pode ser um indicador desse traço de personalidade
92

Hesitação e ousadia na tilápia-do-Nilo : identificação, comunicação intraespecífica e papel social /

Silva, Graziela Valença da. January 2014 (has links)
Orientador: Gilson Luiz Volpato / Banca: Leonardo José Gil Barcellos / Banca: Amauri Gouveia Junior / Banca: Marisa Fernandes Castilho / Banca: Rodrigo Egydio Barreto / Resumo: Avaliamos a associação entre o escurecimento do olho e a hesitação na tilápia-do-Nilo, Oreochromis niloticus. Para isso, mensuramos a porcentagem de escurecimento da esclera (cor do olho basal) de 48 peixes, que estavam isolados por 4 dias. Em seguida, avaliamos a hesitação e ousadia por meio do teste do objeto novo. Após 24 h, mensuramos novamente a cor do olho (cor pré-hipóxia) e submetemos o peixe a estressor (hipóxia: 2 min fora d'água), registrando a cor do olho imediatamente após esse estressor (cor pós-hipóxia). Ao retornarem ao aquário, avaliamos o tempo para o olho retornar à cor pré-hipóxia. O tempo despendido na exploração do objeto variou de 0 a 570 s. Desses dados, identificamos peixes hesitantes (1º quartil: Q1=0 a 10 s) e ousados (3º quartil: Q3=231 a 570 s). Os hesitantes tinham o olho mais escuro antes do teste do objeto novo (cor basal) e antes do estressor (pré-hipóxia). Com a hipóxia, todos os peixes escureceram o olho, mas o retorno à cor pré-hipóxia demorou mais nos hesitantes. O sexo não interferiu nessas respostas. Concluímos que o escurecimento do olho está associado à hesitação na tilápia-do-Nilo, o qual pode ser um indicador desse traço de personalidade / Abstract: Not available / Doutor
93

A complexidade do repertório acústico das capivaras (Hydrochoerus hydrochaeris) / The complexity of capybaras acoustic repertoire (Hydrochoerus hydrochaeris)

Cintia Tomoe Suzuki 18 February 2016 (has links)
A capivara é uma espécie altamente social que vive em grupos multi-macho e multi-fêmea hierarquicamente organizados. Um rico repertório de comportamentos, incluindo o acústico, regula as interações sociais e organiza a vida em sociedade. Para investigar o repertório acústico da espécie realizamos o levantamento e a descrição categorizada das vocalizações. Os sinais acústicos foram registrados a partir de uma população de vida livre habitante do campus da USP de Ribeirão Preto e um grupo de capivaras do Bosque e Zoológico Municipal Fábio Barreto, em Ribeirão Preto. Nossos resultados mostram a existência de dez sinais acústicos, alguns deles com 3 a 4 variantes, o uso de um sistema de combinação de notas, e a presença de efeitos não-lineares em sinais relacionados a estados internos alterados como no grito de agonia emitido durante a contenção. Os resultados encontrados apontam para uma riqueza maior e mais variada de chamados já descritos na literatura revelando um repertório acústico comparável com o descrito para o mocó (Kerodon rupestris), o preá (Cavia aperea) e outros caviomorfos. O registro de outros níveis de organização de notas e a presença de elementos não-lineares também enriquecem o sistema de comunicação da espécie e demostram a sua complexidade. Nossos resultados vêm trazer contribuições de forma a complementar a descrição do repertório da espécie que se mostrou maior e mais complexa / The capybara is a highly social species that lives in hierarchically organized multi-male/multi-female groups. A rich behavioral repertoire, including acoustic signalization, mediates social interactions and life in society. To investigate the acoustic repertoire of this species we conducted a survey and categorization of calls. The acoustic signals were registered from a population living free local campus of USP in Ribeirão Preto and of a captive group (Bosque e Zoológico Municipal Fábio Barreto) in the municipality of Ribeirão Preto. Our results show the existence of ten different acoustic signals, some of them subdivided in 3 to 4 variant, and the use of note composition from two different types, and non-linearity in distress signals, as those produced by under containment individuals. The results point to a larger and more varied richness of calls already described in the literature showing an acoustic repertoire comparable to that described for the mocó (Kerodon rupestris) , the guinea pig (Cavia aperea) and other caviomorph . The registry of other levels of organization of notes and the presence of non - linear elements also enrich the communication system of the species and demonstrate its complexity. Our results come bring contributions to complement the description of the repertoire of the species that was larger and more complex
94

A memória de um gesto comunicativa humano no cão doméstico (Canis familiaris) / Memory of a communicative human gesture in the domestic dog (Canis familiaris)

Maria Mascarenhas Brandão 14 May 2012 (has links)
São diversos os estudos sobre a compreensão de dicas comunicativas humanas pelo cão. Em todos eles, a verificação da compreensão do sinal é realizada imediatamente após a emissão do mesmo. A nossa pesquisa busca refletir sobre os processos de memória envolvidos na operação de designação-busca do objeto escondido pelo cão, tendo como objetivo investigar a memória operacional dos cães para um sinal comunicativo humano. Comparamos a retenção de informações para duas condições: quando o cão tinha contato visual direto com o objeto-alvo (não-comunicativa) e quando recebia a informação a respeito da localização do alvo por um sinal comunicativo humano (comunicativa). Num primeiro experimento, quisemos saber como a retenção das informações era afetada em função do intervalo de tempo decorrido para as duas condições. Em outro, também para as duas condições, como a retenção da informação, em um mesmo intervalo de tempo, era afetada em função de diferentes tipos de distração. Para tanto, utilizamos nos dois experimentos uma tarefa de busca pelo objeto escondido, em que o cão recebia a informação sobre a localização de um alimento desejado em uma de duas caixas, esperava por um intervalo retido atrás de um anteparo (barreira visual) e depois era liberado e poderia aproximar-se de uma das caixas. Na condição indicação gestual (comunicativa), a informação era dada pelo experimentador em um gesto de apontar proximal momentâneo. Na condição observação, o cão podia ver o alimento disponível em uma de duas caixas após a colocação do anteparo as caixas eram giradas e o cão perdia a visão do objeto. No Experimento I, os sujeitos recebiam a informação e eram liberados para responder após intervalos de 5, 60 ou 240 segundos. Os resultados indicaram uma tendência à significância nas respostas dos sujeitos no intervalo de 60 segundos, favorecendo a condição indicação gestual. No experimento II, os sujeitos eram testados no mesmo intervalo de retenção (60 segundos), mas variavam as situações de distração entre as tentativas: distração por comando (comunicativa) ou por deslocamento (não-comunicativa), além de uma tentativa controle (sem distração). Os resultados indicam que as distrações não tiveram efeitos significativos para nenhuma das condições. De maneira geral, podemos concluir que a informação transmitida por um gesto comunicativo humano (o apontar do local onde está escondido alimento) pode ser conservada na memória e que ela tem um trajeto mnemônico semelhante a outros constatados no estudo da cognição de cães / There are many studies regarding the comprehension of human cues by dogs. In all of them, the comprehension of the cue is verified immediately after its emission. Our research intends to reflect over the memory processes involved in the operation of designation-search of a hidden object by the dog, with the objective of investigating the dogs operational memory for a communicative human sign. We compared the informations retention under two conditions: when the dog had direct visual contact with the target-object (non-communicative situation) and when it received information regarding the targets location through a human communicative sign (communicative situation). In the first experiment, we wanted to know how the informations retention was affected based on the elapsed time for the two conditions. In another experiment, for the same two conditions, we wanted to know how the informations retention, under only one latency period, was affected based on different types of distraction. To do so, we utilized in both experiments a object search task, in which the dog received information regarding the location of a desired piece of food in one of two boxes. The dog was retained for a certain latency period, recluse behind a screen (visual barrier), and then was released and could approach one of the boxes. Under the gestural indication condition (communicative situation), information was given by the experimenter, using a proximal momentary pointing gesture. Under the observation condition, the dog could see the piece of food available in one of two boxes which were turned after the screen was placed, making the dog lose sight of the object. In Experiment I, the subjects received information and were released to respond after a time frame of 5, 60 or 240 seconds. The results indicate a tendency of a difference in the performance of dogs in the 60 seconds-latency period, favoring the gestural indication condition. In Experiment II, the subjects were tested under the same retention latency period (60 seconds), but the distraction situations vary between the attempts: command distraction (communicative situation) or dislocation distraction (non-communicative), besides a control situation (without distraction). The results point that the distractions had no significant effects for neither the conditions. In general, we can conclude that the transmitted information through a human communicative gesture (pointing the location where the food is hidden) can be conserved in the dogs memory and that it has a mnemonic path similar to others found in studies of the dogs cognition
95

Studies on mixed-species colonies of honeybees, Apis cerana and Apis mellifera

Yang, Ming-Xian January 2010 (has links)
The honeybees Apis cerana and Apis mellifera are derived from the same ancestral base about two million years ago. With speciation and evolution, they have acquired many advanced living skills in common, but have also evolved very different living strategies due to different distributions. This thesis is an intensive study of the biology of the mixed-species colonies of these species, the aims of which were to investigate their behavioural relationships and uncover the evolutionary conserved features of their behaviours subsequent to speciation. The results show that the two species can form a stable society to perform normal tasks. First, workers of both species in the mixed-colonies could form the typical retinue behaviour to hetero-species queens, thus indicating that queen pheromones could be spread to and by both species. Secondly, both species did not show significantly different ovarian activation under hetero-species queens, suggesting that the queen pheromones more likely play a role of "honest signal" rather than a "repression" substance in the honeybee colonies. Thirdly, both species could mutually decode each other‘s waggle dances, with unexpectedly low misunderstanding; revealing that the dance language in a dark environment is quite adaptive for cavity-nesting honeybees. Fourthly, workers of both species could cooperate with each other in comb construction, although the combs they built contain many irregular cells. Interestingly, A. cerana workers could be stimulated by A. mellifera workers to perform this task, thus confirming self-organization theory in the colony. Fifthly, A. mellifera workers behaved more "defectively" in thermoregulation, but perhaps because A. cerana workers are more sensitive to changes in hive temperature. Given these differences in strategy, A. mellifera workers‘ performance might in fact reduce conflicts. Lastly, when faced with threats of predatory wasps, both species engaged in aggressive defence. Although they did not learn from each other‘s responses, species-specific strategies were adopted by each of them so that the defence of the mixed-colonies is very effective. I conclude that the two species can adapt to each other‘s efforts and task allocation is reasonably organized allowing mixed-species colonies to reach stability. These results suggest that all of the social behaviours discussed here were highly conserved following speciation. This thesis could provide some clues for the study of honeybee evolution from open-nesting to the transition of cavity-nesting.
96

Shaping Cows' Approach to Humans Using Positive and Negative Reinforcement

Morehead, Melissa L. 05 1900 (has links)
Negative reinforcement can be a powerful tool for behavior analysts, yet it is often overlooked as a treatment method. Pryor (1999) outlines a method for approaching a "timid" animal using a combination of negative reinforcement and positive reinforcement. When the animal stands still, the human operates a clicker, and then retreats from the animal. Gradually, the human moves closer to the animal through the clicking and retreating shaping process. Once the human is standing close enough, food may be offered as a positive reinforcer, and the negative reinforcer is canceled out. The purpose of this study was to experimentally demonstrate the click-retreat technique with cows. A multiple-baseline design across subjects was used to test this technique. Results show that the click and retreat technique was effective. Results are discussed in terms of the difference between the click-retreat technique and systematic desensitization.
97

Social and Environmental Regulation of Signal Plasticity and Signal Reliability in the Electric Fish Brachyhypopomus gauderio

Gavassa Becerra, Sat 28 June 2012 (has links)
The balance between the costs and benefits of conspicuous signals ensures that the expression of those signals is related to the quality of the bearer. Plastic signals could enable males to maximize conspicuous traits to impress mates and competitors, but reduce the expression of those traits to minimize signaling costs, potentially compromising the information conveyed by the signals. I investigated the effect of signal enhancement on the information coded by the biphasic electric signal pulse of the gymnotiform fish Brachyhypopomus gauderio. Increases in population density drive males to enhance the amplitude of their signals. I found that signal amplitude enhancement improves the information about the signaler’s size. Furthermore, I found that the elongation of the signal’s second phase conveys information about androgen levels in both sexes, gonad size in males and estrogen levels in females. Androgens link the duration of the signal’s second phase to other androgen-mediated traits making the signal an honest indicator of reproductive state and aggressive motivation. Signal amplitude enhancement facilitates the assessment of the signaler’s resource holding potential, important for male-male interactions, while signal duration provides information about aggressive motivation to same-sex competitors and reproductive state to the opposite sex. Moreover, I found that female signals also change in accordance to the social environment. Females also increase the amplitude of their signal when population density increases and elongate the duration of their signal’s second phase when the sex ratio becomes female-biased. Indicating that some degree of sexual selection operates in females. I studied whether male B. gauderio use signal plasticity to reduce the cost of reproductive signaling when energy is limited. Surprisingly, I found that food limitation promotes the investment in reproduction manifested as signal enhancement and elevated androgen levels. The short lifespan and single breeding season of B. gauderio diminishes the advantage of energy savings and gives priority to sustaining reproduction. I conclude that the electric signal of B. gauderio provides reliable information about the signaler, the quality of this information is reinforced rather than degraded with signal enhancement.
98

OLFACTORY COMMUNICATION IN THE MALE GRAY SHORT-TAILED OPOSSUM (MONODELPHIS DOMESTICA)

Hall, Jessica Alaina 25 September 2012 (has links)
No description available.
99

Gestural communication in orangutans (Pongo pygmaeus and Pongo abelii) : a cognitive approach

Cartmill, Erica A. January 2009 (has links)
While most human language is expressed verbally, the gestures produced concurrent to speech provide additional information, help listeners interpret meaning, and provide insight into the cognitive processes of the speaker. Several theories have suggested that gesture played an important, possibly central, role in the evolution of language. Great apes have been shown to use gestures flexibly in different situations and to modify their gestures in response to changing contexts. However, it has not previously been determined whether ape gestures are defined by structural variables, carry meaning, are used to intentionally communicate specific information to others, or can be used strategically to overcome miscommunication. To investigate these questions, I studied three captive populations of orangutans (Pongo pygmaeus and P. abelii) in European zoos for 10 months. Sixty-four different gestures, defined through similarities in structure and use, were included in the study after meeting strict criteria for intentional usage. More than half of the gesture types were found to coincide frequently with specific goals of signallers, and were accordingly identified as having meanings. Both structural and social variables were found to determine gesture meaning. The recipient’s gaze in both the present and the past, and the recipient’s apparent understanding of the signaller’s gestures, affected the strategies orangutans employed in their attempts to communicate when confronted with different types of communicative failure (e.g. not seeing, ignoring, misunderstanding, or rejecting a gesture). Maternal influence affected the object-directed behaviour and gestures of infants, who shared more gestures with their mothers than with other females. These findings demonstrate that gesture can be used as a medium to investigate not only the communication but also the cognition of great apes, and indicate that orangutans are more sensitive to the perceptions and knowledge states of others than previously thought.
100

Acoustic Tonal and Vector Properties of Red Hind Grouper Vocalizationd

Unknown Date (has links)
Vertebrates are the most prodigious vocalizing animals in existence, and the most diverse methods of acoustic communication among vertebrates can be found in the ocean. Relatively many teleost fish are gifted with the ability to communicate acoustically, and the family of serranidae often performs this as a function of the swim bladder. Epinephelus Guttatus (E. guttatus), or more commonly the red hind grouper, is equipped with a drum shaped swim bladder acting as a monopole under typical ocean conditions. This configuration allows for what is understood to be omnidirectional projection of tones approximately centered between 40 and 440 Hz and spanning anywhere from 40 to 200 Hz of bandwidth and modulation effects based on observed data provided by researchers. Prior studies on many other fish show correlation in acoustic communication profile with length, size and sexual identity. In the red hind, sexual dimorphism leads to an inherent female identity in all juvenile fish which converts to male according to environmental factors, recommending at least consistent organs across both sexes be assumed even if not in use. Much research has been performed on male fish vocalization in terms of spectral content. Communication in fish is a complex multi-modal process, with acoustic communication being important for many of the species, particularly those in the littoral regions of the worlds’ oceans. If identifying characteristics of the red hind vocalization can be isolated based on detection, classification, tracking and localizing methodologies, then these identifying characteristics may indeed lead to passive feature identification that allows for estimation of individual fish mass. Hypotheses based on vector, cyclostationary and classical tonal mechanics are presented for consideration. A battery of test data collection events, applying pre-recorded fish vocalizations to a geolocated undersea sound source were conducted. The results are supplied with the intent of validating hypothesis in a non-expert system manner that shows how a series of biological metrics may be assessed for detection, classification, localization and mass estimation for an individual vocalizing red hind grouper / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection

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