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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

POPULATION CYTOGENETICS OF THE COMMON CHIMPANZEE PAN TROGLODYTES (CHROMOSOMES, EVOLUTION, PRIMATES).

MARKS, JONATHAN MITCHELL. January 1984 (has links)
First, the literature on hominoid cytogenetics is reviewed and evaluated. It is suggested that there are significant deficiencies in the ways in which chromosomal data have been used with regard to primate evolution. The most robust chromosomal data support an orthodox phylogeny of the Hominoidea. Heterodox phylogenies which have been suggested on the basis of chromosomal data are not well supported. The present investigation considered the problem of intra-specific variation in karyotypes of the common chimpanzee. Blood cultures were cultivated on 25 chimpanzees, constituting the largest sample of chimpanzees in a single cytogenetic study. These were studied by G-banding, C-banding and nucleolar organizer (Ag-NOR) staining. No inversions, translocations, fissions or fusions were detected in this sample. However, several variations of the constitutive heterochromatin and nucleolar organizers were noted. One individual had a chromosome 22 which lacked the heterochromatic short arm and satellite entirely. The most common variants were those in which the amount of telomeric heterochromatin differed significantly between the two homologous chromosomes. One such variant for chromosome 19 was found in 8 individuals. Two of the common chimpanzees possessed a chromosome 23 with a large heterochromatic short arm, although this feature has been reported only for the pygmy chimpanzee. To compare the observable range of variation in the common chimpanzee with its sister group, fibroblast cultures were obtained on three pygmy chimpanzees. Some of the cytotaxonomic distinctions between the two chimpanzee species are called into question. Three main conclusions are drawn from this work. First, the most common kinds of variations are nucleolar organizer and C-band heteromorphisms, as with the chimpanzee's close relative Homo sapiens. Second, inversions and translocations, which seem to be very common among gibbons but not among macaques/baboons, are not common in chimpanzees. This is in accordance with the hypothesis that such structural chromosomal diversity is a property of the social structure of the species rather than a property of the clade to which the species belongs. Third, there is some overlap between Pan paniscus and Pan troglodytes for characters which have been thought to be cytotaxonomically distinctive of each species.
22

Intra-sexual competition and vocal counter-strategies in wild female chimpanzees (Pan troglodytes schweinfurthii)

Townsend, Simon W. January 2009 (has links)
A growing body of behavioural data is beginning to show that, like their male counterparts, female chimpanzees can be competitive and aggressive, particularly when resources come under pressure. These observations are especially surprising because, for a long time, females were simply considered passive pawns of male social manoeuvrings. While we are beginning to understand the complexities surrounding female chimpanzee group living, exactly how females manage these social pressures is unclear. In this thesis I address this by focusing on female competition in wild chimpanzees and the importance of vocal counter-strategies. I examined two commonly produced female vocalisations: copulation calls and victim screams from chimpanzees (Pan troglodytes schweinfurthii) in the Budongo Forest, Uganda. My results regarding the production and acoustic structure of copulation calls suggests that these vocalisations play a crucial role in the lives of female chimpanzees, dissipating the risks associated with female competition. During aggression, chimpanzee females commonly produce victim screams and these calls have been shown to vary systematically with the severity of aggression experienced. A playback experiment showed that victim screams are meaningful to females and that listeners do not just respond to the acoustically most salient signals in their environment. Females may use this information to keep track of out-of-sight agonistic interactions and make appropriate social decisions regarding whether to avoid an ensuing attack. Taken together, I propose that vocalisations may represent important behavioural counter-strategies, enabling females to navigate successfully through their socially intricate world.
23

A cognitive approach to the study of culture in wild chimpanzees (Pan troglodytes schweinfurthii)

Gruber, Thibaud January 2011 (has links)
The question of animal culture has been of interest for decades. Chimpanzees (Pan troglodytes) have played a key role in the debate of whether or not it is appropriate to use the term ‘culture' to describe animal behaviour and they continue to be one of the prime species for the study of the origins of human culture. Data suggesting that chimpanzees can be considered a cultural species continue to accumulate, but this has only enhanced the debate between proponents and opponents of animal culture. Opponents do not deny that behavioural diversity exists between different populations of the same species, but they maintain that such phenomena have little to do with human cultures and may be the result of genetic and environmental influences. In their view, human cultures are centred on socially shared sets of ideas, not behavioural traditions. In this thesis, my goal is to tackle this problem and to investigate whether a cognitive dimension can be found in some behavioural patterns of chimpanzees that have been put forward as examples of animal culture. To this end, I examine the different factors that could account for the development of tool use in animals (genetics, ecology, social). My first empirical contribution is a study of the tool use behaviour of the chimpanzees' closest relative, the bonobos, which are known to be limited tool-users in the wild. I show that captive bonobos are as flexible tool-users as chimpanzees, suggesting that genetic factors are unlikely to account for differences in tool use behaviour in the Pan clade. Second, through the use of field experiments, I show that wild chimpanzees from different Ugandan communities respond to the same apparatus and task in strikingly different ways. I interpret this finding as an outcome of differences in cultural knowledge, mainly because the affordances of their immediate environment do not determine their tool use behaviour. Finally, through a broad ecological and tool use survey of different chimpanzee communities in Uganda, I show that current ecological differences are poor predictors of tool use. I conclude that, if ecology plays a role in the development of tool use, then its influence is that of a selective force. Finally, when reviewing the outcome of this research I will argue that there is a profound cognitive dimension to tool use in wild chimpanzees, suggesting that behaviourally based definitions of animal culture may miss a key feature of the phenomenon, at least in chimpanzees. Chimpanzees are not only a cultural species, they also have a cultural mind.
24

Sexual behaviour and mating patterns in a community of wild chimpanzees (Pan troglodytes schweinfurthii)

Tutin, Caroline Elizabeth Gaskell January 1975 (has links)
The aim of the study was to describe the reproductive biology of wild chimpanzees (Pan troglodytes schweinfurthi) and to relate this to aspects of their ecology and social organisation. Within this general framework the specific aims were: (a) To determine the reproductive potential of female chimpanzees and to assess the limits this places on species' reproduction; (b) To examine the adaptive significance of female reproductive physiology in terms of optimal reproductive success; (c) To examine environmental constraints on reproduction; (d) To describe copulatory behaviour and the nature of the three mating patterns shown by wild chimpanzees, and to assess the adaptive significance of the flexible mating system; (e) To relate reproductive behaviour to social organisation in an attempt to assess the role of sexual selection in the evolution of chimpanzee social behaviour and structure.
25

Operant Methodology Out Of The Lab and Applied To Enrichment With Captive Chimpanzees (Pan Troglodytes)

Vivian, Melanie January 2008 (has links)
A group of socially-housed chimpanzees, maintained in a zoo facility, were given the opportunity to access each of several purpose-designed and built enrichment items. Each item was made freely available in the chimpanzees' regular setting, with their normal activities available. The time members of the group spent engaging with each item gave an assessment of their relative preference for the items. The group were shown to have the greatest preference for a foraging enrichment item (Screwfeeder) and the least preference for an audiovisual enrichment item (TV/Video). Individual preferences for the items were evident. The chimpanzees were then taught to operate a weighted lever to get access to an item. Once all chimpanzees had operated the lever for access to the items, the number of lever operations required for access to each item was systematically doubled over a series of 3 hr sessions until the chimpanzees did not gain any access to that item for two consecutive sessions. One item was presented for two series of increases. The group response rates for an item increased with increased response requirement and then decreased with further increases, reflecting data from individuals in other research. The highest response requirement that maintained the group behaviour differed over the items. The number of times an item was accessed (consumption) was plotted against the response requirement (price) on logarithmic coordinates. Lines fitted to the data (demand functions) were shallowest for a foraging enrichment (Screwfeeder) and steepest for the audio enrichment (Musicbox). There were not enough data points to fit a function for the audiovisual enrichment. Differences in individual's demand within the group were evident. In general, the rank order of preference for the items and the rank order based on the parameters of the demand functions (slope or elasticity and initial intensity) was broadly the same. Three individual chimpanzees were exposed to two series of increasing response requirement for access to the Screwfeeder whilst housed alone, in one hour sessions. Response rates were again bitonic and the linear demand functions for these individuals were steeper (more elastic) than the functions fitted to data for group responding and differed idiosyncratically from the data for these individual when responding as part of the group. Thus the change of social setting had a different impact on the behaviour of each of the individuals. These results show that an animals‟ demand for a commodity is altered by the environment in which it is tested. ii Overall the research provides the first example of operant methodology in a zoo setting with a group of chimpanzees. It is also the first research to show differential responding for access to different enrichment items by a group and how this relates to their preference (based on time allocation) for those items.
26

The effects of second-order discriminations on complex performance in a chimpanzee

Melia, Kathleen F. 12 1900 (has links)
No description available.
27

Evolutionary origins of technological behaviour : a primate archaeology approach to chimpanzees

Marques de Carvalho, Susana Claudia Ribeiro January 2013 (has links)
No description available.
28

The facilitation of exploratory behaviour and other behavioural changes by the presentation of novel objects to rats (Rattus norvegicus), chimpanzees (Pan troglodytes) and caracals (Felis caracal) / Carla Litchfield.

Litchfield, Carla Anita January 2000 (has links)
Includes bibliographical references (leaves 873-896). / xxxvi, 896 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Reports on 2 experiments which investigated exploratory & other behaviour in the laboratory rat during fixed-interval, variable-interval, variable-ration and differential reinforcement of low rates schedules of reinforcement (& subsequent extinction.) A third experiment investigated exploratory & other behaviours in an open-field Skinner box during a fixed-interval schedule, with a concurrently available water source. The final experiments were conducted on a qualitative analysis basis at Adelaide Zoo. A number of novel objects were presented to a group of six chimpanzees, and a different set of objects presented to a pair of caracals, in an attempt to facilitate exploratory behaviour and reduce abberant behaviours. / Thesis (Ph.D.)--Adelaide University, Dept. of Psychology, 2001
29

Assessment of the impact of a newly introduced free-ranging group of chimpanzees (Pan troglodytes schweinfurthii) on the vegetation of Ngamba Island, Lake Victoria, Uganda

Schoene, Claudia Ulrike Regina. January 2003 (has links)
Thesis (M. Sc.)(Wildlife Management)--University of Pretoria, 2003. / Abstract in English. Includes bibliographical references.
30

Functional analysis and treatment of human-directed undesirable behaviors in captive chimpanzees (Pan troglodytes)

Martin, Allison L. January 2008 (has links)
Thesis (M. S.)--Psychology, Georgia Institute of Technology, 2009. / Committee Chair: Maple, Terry L.; Committee Member: Bloomsmith, Mollie A.; Committee Member: Kelley, Michael E.; Committee Member: Marr, M. Jackson. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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