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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.
21

Ovarian function and reproductive behaviors across the female orangutan life cycle

Durgavich, Lara 24 February 2016 (has links)
Due to their phylogenetic position as an outgroup to humans and the other African apes, empirical data from orangutans are an especially valuable comparative tool with which questions about the evolution of human life history and reproductive characteristics can be addressed. Yet few such data are available. In this dissertation, I use endocrinological and behavioral data from 7 female and 3 male orangutans housed at the Woodland Park Zoo in Washington and the Great Ape Trust in Iowa to characterize the ovarian function and reproductive behaviors of captive female orangutans at different points in the life cycle. Ovarian hormone measurements were achieved through the use of non-invasive urine sampling, and assays reveal both intra- and inter-individual variation in hormone production. Results indicate that (1) adolescent females in captivity do not experience a marked period of subfecund estrogen and progesterone levels in association with reproductive maturation, (2) individual females exhibit both "high quality" and "low quality" cycles, including instances of anovulation, in the absence of fluctuating dietary and environmental conditions, (3) mating behaviors vary between individuals and with cycle phase, but are not strongly influenced by absolute ovarian hormone concentrations, and (4) reproductive senescence does not significantly impact the ovarian function and mating behaviors of aging female orangutans. These results demonstrate that many aspects of human reproductive biology and behavior, such as an extended period of mating receptivity, are evolutionarily conserved. They suggest, however, that the decline in human ovarian function in mid-life may be derived and of possible adaptive significance. The potential significance of differences between captive and wild ape populations, and the character, history, and familial relationships of the particular individuals discussed are considered in the interpretation of all data.
22

The origin of prosociality and fairness: Perspectives from experiments with orangutans / 向社会性と公平性の起源:オランウータンでの実験研究からの視点

Kim, Yena 25 September 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20660号 / 理博第4325号 / 新制||理||1621(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 友永 雅己, 准教授 足立 幾磨, 准教授 鈴木 樹理 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
23

Le rôle des organisations de conservation dans la construction et la mise en œuvre de l'agenda international de conservation d'espèces emblématiques : le cas des orangs-outans de Sumatra / The role of conservation organizations in the construction and implementation of the international conservation agenda for emblematic species : the case of Sumatran orangutan

Ruysschaert, Denis 23 September 2013 (has links)
La thèse analyse le rôle des organisations de conservation dans la contradiction croissante entre, d’une part, la formalisation continue d’un cadre politique - juridique - institutionnel - financier - médiatique pour la conservation de l’orang-outang de Sumatra et, d’autre part, le constat avéré du déclin continu de son habitat et de ses populations. Partant du niveau global, elle se concentre ensuite dans le contexte indonésien, porteur d’un conflit aigu autour de la transformation de la forêt de basse altitude -habitat de l’orang-outan de Sumatra- en culture de palmier à huile.Le rôle des organisations de conservation sont étudiées à travers quatre dimensions sociologiques : l’établissement des référentiels globaux de conservation, la construction scientifique des indicateurs de référence, la mise en œuvre du droit indonésien et l’application de l’accord volontaire du RSPO.La thèse a trouvé des réponses concluantes pour chaque dimension et transversalement. Sans minimiser le rôle de l'état et du secteur privé, les ONG jouent aussi un rôle décisif dans le maintien du problème. Deux constantes sont observées : l'une est leur difficulté à tenir compte de la société qui abrite les populations d'orangs-outans, l'autre est leur propension à privilégier leurs propres intérêts afin de perdurer dans le champ social au détriment de leur objectif initial de conservation. Se préoccuper à ces deux manquements est le défi contemporain de la conservation. Des pistes sont donc données dans la conclusion pour refondre la gouvernance internationale de la conservation et pour redéfinir stratégiquement le rôle des ONG de conservation. Cette thèse est basée sur près de vingt ans d'expérience dans la gestion de l'environnement - à la fois pour des organisations de conservation et les Nations Unies - et 49 entretiens semi-directifs. / The thesis analyses the role of conservation organizations in the growing contradiction between, on the one hand a continuous and regular formalisation of a framework (political - legal - institutional - financial - media) for Sumatran orangutan conservation, and on the other hand, a proven report of the continuous decline of orangutan habitat and populations. Starting at the global level, the thesis then focuses on the Indonesian context that gives rise to an acute conflict centred on lowland primary tropical forest - the exclusive habitat of Sumatran orangutans - being converted into large-scale oil palm plantations. The role of conservation organizations has been studied through four sociological dimensions: i) the establishment of global paradigms for conservation, analysing in particular the Great Ape Survival Partnership - GRASP; ii) the "scientific" construction of reference indicators that characterise the orangutan; iii) the establishment and implementation of law at Indonesian level; and iv) the application of the voluntary agreement Roundtable on Sustainable Palm Oil - RSPO. The overall understanding of the role of NGOs is then given by the cross- analysis of the results under these four angles. The thesis has found articulated and conclusive answers for each dimension. Without underestimating the role of the state and the private sector, the cross-analysis shows that NGOs also play a decisive role in maintaining the problem of habitat loss and the decline of emblematic species, in particular the Sumatran orangutan. Two concomitant constants are observed. One is their difficulty to productively engage with the society that supports the wild orangutan populations. The other is their tendency to prioritize their own interests to perpetrate in the social and political sphere at the expense of their initial conservation objectives. To address these two structural shortcomings is the contemporary challenge for conservation. In the conclusion, suggested paths are given, both to reform international biodiversity governance and to strategically reorient the role of conservation organizations. The thesis is based on information gathered during twenty-years of experience in environmental protection - both in the United Nations and conservation organisations - and 49 semi-structured interviews.
24

Attention following and nonverbal referential communication in bonobos (Pan paniscus), chimpanzees (Pan troglodytes) and orangutans (Pongo pygmaeus)

Madsen, Elainie Alenkær January 2011 (has links)
A central issue in the study of primate communication is the extent to which individuals adjust their behaviour to the attention and signals of others, and manipulate others’ attention to communicate about external events. I investigated whether 13 chimpanzees (Pan troglodytes spp.), 11 bonobos (Pan paniscus), and 7 orangutans (Pongo pygmaeus pygmaeus) followed conspecific attention and led others to distal locations. Individuals were presented with a novel stimulus, to test if they would lead a conspecific to detect it in two experimental conditions. In one the conspecific faced the communicator, while another required the communicator to first attract the attention of a conspecific. All species followed conspecific attention, but only bonobos in conditions that required geometric attention following and that the communicator first attract the conspecific‘s attention. There was a clear trend for the chimpanzees to selectively produce a stimulus directional ‘hunching’ posture when viewing the stimulus in the presence of a conspecific rather than alone (the comparison was statistically non-significant, but very closely approached significance [p = 0.056]), and the behaviour consistently led conspecifics to look towards the stimulus. An observational study showed that ‘hunching’ only occurred in the context of attention following. Some chimpanzees and bonobos consistently and selectively combined functionally different behaviours (consisting of sequential auditory-stimulus-directional-behaviours), when viewing the stimulus in the presence of a non-attentive conspecific, although at species level this did not yield significant effects. While the design did not eliminate the possibility of a social referencing motive (“look and help me decide how to respond”), the coupling of auditory cues followed by directional cues towards a novel object, is consistent with a declarative and social referential interpretation of non-verbal deixis. An exploratory study, which applied the ‘Social Attention Hypothesis’ (that individuals accord and receive attention as a function of dominance) to attention following, showed that chimpanzees were more likely to follow the attention of the dominant individual. Overall, the results suggest that the paucity of observed referential behaviours in apes may owe to the inconspicuousness and multi-faceted nature of the behaviours.
25

Orangutan health and behavior: Implications for nutrition in captivity

Hamilla, Rachel A., Hamilla 07 May 2018 (has links)
No description available.
26

"Our Primate Materials" Robert M. Yerkes and the Introduction of the Primate to Problems of Human Betterment in the American Eugenics Movement

Caitlin Marie Garcia-Feehan (15348619) 27 April 2023 (has links)
<p>My thesis examines how eugenicist and psychologist Robert M. Yerkes’ experimental intelligence research helped to situate the non-human primate as the ideal research subject for human betterment research in the twentieth century U.S. Yerkes believed that the primate was the ideal research subject to address questions of human betterment and social welfare, specifically best to create methods of evaluating the imagined threat of intellectual disability. While Yerkes has been studied extensively in the history of psychology, primatology, and eugenics, rarely have his separate contributions to these fields been placed in conversation with one another. Placing the primate at the center of Yerkes’ work allows for all three fields to engage with one another in a new perspective. By analyzing Yerkes’ publications about the Multiple-Choice Experiment within the context of the American eugenics’ movement, we can see how the primate came to hold a central position in U.S. scientific research, the advancement of human welfare and betterment, and as a means of defining what it means to be human. This story offers a glimpse into this longer process of how the primate came to occupy this position, but even a glimpse offers historians of the American eugenics’ movement new questions. What was the role of the non-human animal in the formulation of American eugenic theories? How have we historically used the natural world in our attempts to separate ourselves from it? And can we truly reconcile a history with eugenics if we continue to ignore the role of animals within it, they who today exist unquestionably within the status of the sub-human?</p>

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