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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

An examination of social arousal and its implications for social congnition in the South African vervet monkey / Petra L. McDougall

McDougall, Petra L, University of Lethbridge. Faculty of Arts and Science January 2010 (has links)
Self-directed behaviours (SDB) were recorded as a behavioural indicator of arousal in free-ranging vervet monkeys (Chlorocebus aethiops) inhabiting the Klein Karoo of South Africa. Measurement of SDB allowed for changes in arousal to be correlated with particular social situations, potentially providing insight into how monkeys perceive their social world. The research presented here is divided into three core chapters demonstrating that 1) arousal is influenced to a greater extent by degree of association than by hierarchical rank, 2) that an individual‟s level of arousal is influenced by its neighbour‟s spatial location, and 3) that habituated animals that no longer perceive humans as a direct threat nevertheless continue to respond to their presence in other ways. Overall, SDB appears to be a useful, non-invasive, simple means of investigating social arousal and its use has elucidated several key findings regarding the perception of social space and social partners in vervet monkeys. / ix, 103 leaves ; 28 cm
92

An investigation of biases in social learning and social attention in wild vervet monkeys (Chlorocebus aethiops pygerythrus) and captive tufted capuchins (Sapajus apella)

Botting, Jennifer Lynette January 2017 (has links)
Researchers in the field of social learning have suggested that certain biases may exist in whom animals learn from, creating a non-random flow of social information. A number of potential biases have been proposed based upon theoretical models, including biases to copy more dominant individuals or individuals who receive the best payoff from their behaviour, but empirical evidence for these biases is lacking. This thesis presents the first examination of dominance-based bias in a wild population of primates and of a payoff-based bias in captive capuchins. In two field experiments, dominant and low-ranking females from each of three wild groups of vervet monkeys (Chlorocebus aethiops pygerythrus) in KwaZulu-Natal, South Africa were trained to demonstrate contrasting behaviours to their group before observers were provided with a choice between the two modelled preferences. No evidence was found for a consistent bias to copy the behaviour of the dominant female in either experiment. Instead, in both experiments, a preference for one behaviour emerged, regardless of model rank. In the latter experiment, higher-ranking females were significantly more likely to match the dominant model's action than were low-ranking females. The low-ranking models were more likely than their high-ranking counterparts to switch behaviours, despite their trained behaviour continuing to be productive. An analyses of the observations revealed that observers were biased towards attending to kin, and observer age appeared to influence access to the dominant models, but no overall preference to attend to the dominant female was found. Together these findings indicate that kinship, sex, age and preferences for specific behaviours are more important factors than model rank in vervet monkey social learning. Finally, I examined whether captive tufted capuchins (Sapajus apella) utilized a payoff-based social learning bias in their foraging decisions. Subjects did not utilize public information when choosing between demonstrated resource-rich and resource-poor sites, suggesting that the social learning abilities of capuchins may not extend to determining the profitability of feeding sites, although limitations of the study are discussed.
93

Distribution, social structure and habitat use of short-finned pilot whale, Globicephala macrorhynchus, in the Canary Islands

Servidio, Antonella January 2014 (has links)
The Canary Archipelago is considered one of the planet's biodiversity hotspots and the short-finned pilot whale is a key species in need of conservation measures. To address a lack of knowledge, almost 2,000 day-surveys were conducted (1999-2012) resulting in 1,094 short-finned pilot whale sightings. The species was recorded year-round and distributed non-uniformly around the archipelago, with greater densities concentrated in patchy areas mainly on the leeward side of the main islands. A total of 1,320 well-marked individuals were identified, which exhibited a large degree of variability in site fidelity (from core residents to transients). Evidence of an island-associated sub-population and a transient one was found. Longitudinal data were used to infer population structure and estimate abundance, while a spatial modelling approach was used to study spatio-temporal patterns in habitat use, distribution and abundance. Spatial modelling revealed habitat preferences in areas between depths of 1000m and 1500m, and higher densities in the south-west of Tenerife and La Gomera (117 short-finned pilot whales recaptured within the two islands). Abundance of 1,980 individuals (CV = 0.33, 95% CI=1,442 – 2,324) was estimated for the entire archipelago, with higher density predicted during the summer months. Mark-recapture analysis estimated 636 resident individuals (CV = 0.028, 95% CI=602 - 671) in the southwest waters of Tenerife between 2007 and 2009. The social and temporal analyses of the behavioural relationships between pairs of individuals revealed a well-differentiated society with long-lasting and non-random social structure built of constant companions. A hierarchical social system is proposed composed of a population encompassing several clans of pilot whales, each one containing several pods. Nine long-term units were identified with a high degree of association (0.62 - 0.83). This study, the first to provide combined results on distribution, habitat use, and social structure of the species, provides essential information towards the development of recommendations for much needed conservation measures.
94

Negotiating social space in vervet monkeys

Matlock, Alena, University of Lethbridge. Faculty of Arts and Science January 2013 (has links)
This study explores the effect of changing ecological conditions on female social organization among free-ranging vervet monkeys (Cholorocebus aethiops pygerythrus) in the Klein Karoo, South Africa. Comparison was made between a previous study conducted during a period of drought in 2009, and my own study conducted when conditions were much wetter and hence, less ecologically stressful. In addition, animals in the present study also experienced conditions of low demographic stress. Compared to 2009, females displayed lower rates of competition and aggression, did not compete for access to grooming partners, and did not preferentially groom those of high rank, nor did they do so more frequently. Females did, however, preferentially associate spatially with those they groomed most; a finding in contrast to the previous study. Females did not groom those of adjacent ranks more frequently, nor was there any relationship between rank difference and spatial association. In addition, there were rank differences in vigilance were found between females, and vigilance costs overall were affected by total group size. Overall, these findings support some aspects of the socioecological model used to predict group structure in primates, but other aspects of social organization remain puzzling, and may reflect larger overall group sizes in the Samara population, which changes patterns of engagement between females in ways not fully captured by current models. / xi, 122 leaves ; 29 cm
95

Site Fidelity Assessment of Atlantic Bottlenose Dolphins (Tursiops truncatus) Following Large-Scale Emigration of Sympatric Atlantic Spotted Dolphins (Stenella frontalis) in the Bahamas

Unknown Date (has links)
Two sympatric species of dolphins (Atlantic spotted dolphins, Stenella frontalis and Atlantic bottlenose dolphins, Tursiops truncatus) have been long-term residents to Little Bahama Bank. This study assessed whether there was a change in residence patterns or diurnal foraging depths of bottlenose dolphins following a large emigration event in the resident spotted dolphin community on this sandbank. Photo-identification was used to identify individual bottlenose dolphins and compare pooled years before (2010-2012) and after (2013-2015) the spotted dolphin emigration. The identified community size and overall residency of the bottlenose dolphins remained similar, although two bottlenose dolphins emigrated over deep water to the site spotted dolphins emigrated. Bottlenose dolphins diurnally fed in shallower water but remained in the same geographic foraging locations. Reasons remain unknown for this depth change, but potential changes in the productivity of primary bottlenose dolphin foraging habitats or reduction of spotted dolphins from shallower depths remain possibilities. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
96

Intra and interspecies association patterns of Atlantic spotted dolphins, Stenella frontalis, and Atlantic bottlenose dolphins, Tursiops truncatus, and the effects of demographic changes following two major hurricanes

Unknown Date (has links)
Demographic changes, through immigration/emigration (or death) can affect the social and community structure of a population. This study reports on the effects of demographic changes following 2 intense hurricanes on two sympatric delphinid species: Atlantic bottlenose dolphins, Tursiops truncatus, and Atlantic spotted dolphins Stenella frontalis. Thirty percent of the bottlenose population was lost after the hurricanes, with an influx of roughly the same number of immigrants. The stable community split into two cohesive units. Preferences in association in relation to reproductive status and sex remained. Immigrants assimilated well into the population, especially males. There is a conflict of interest between resident males and females in accepting immigrants and often females find more resistance than males. Long-term analysis of spotted dolphins revealed a community structure defined by long-term site fidelity, natal philopatry of both sexes and three social clusters. / Female associations were influenced by reproductive status and social familiarity within clusters. Males formed long-term alliances and shorter-term coalitions. Some movement between clusters occurred. Alliance formation crystallized in adulthood. Mating strategies and sex were the primary factors shaping social structure. Thirty-six percent of the spotted dolphin population was lost after the hurricanes with no influx of immigrants. The spotted dolphin community differed little from long-term analysis, including definitive social clusters and sex preferences. Social cohesion increased within units and across age classes. Some juveniles had associations of alliance level. Loss of individuals resulted in subtle changes in social structure. Interspecies associations reveal striking differences in association patterns between species. Group sizes and re-sightings of spotted dolphins were larger than for bottlenose dolphins, particularly for aggressive encounters. / Male alliances and coalitions were prevalent for spotted dolphins, but not for bottlenose dolphins. After the hurricanes lower re-sighting and group sizes for spotted dolphin males and less aggressive behavior documented, indicates a re-structuring period of relationships between the species. This study shows that environmental variations may alter the structure of mammal societies through demographic upheaval and survival of populations may depend on their social structure and the social adaptability of the species. / by Cindy Rogers Elliser. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
97

Maternal and alloparental discipline in Atlantic spotted dolphins (Stenella frontalis) in the Bahamas

Unknown Date (has links)
Discipline was implemented by mothers and alloparent spotted dolphins (Stenella frontalis) mothers and alloparents on Little Bahama Bank, Bahamas. Disciplinarians were significantly more likely to be adults than juveniles. Although most disciplinarians were female, males were also observed to perform discipline. The recipients of discipline were male and female, and significantly more likely to be calves than juveniles. Pursuit, contact, and display behaviors were used in discipline, however pursuit behaviors were most often observed. Variables such as age class, sex, and parity were not found to influence how discipline was implemented. The durations of all disciplinary pursuits were under thirty seconds, and successful pursuits had slightly shorter duration than unsuccessful pursuits. Disciplinarian success was not significantly influenced by age class, sex, parity, or behavior used. / by Meghan Weinpress. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
98

Diversity and selection in the major histocompatibility complex: DQA and immune function in IRL and Atlantic bottlenose dolphins (Tursiops truncatus)

Unknown Date (has links)
The Major Histocompatibility Complex (MHC) encodes proteins critical to the vertebrate immune response; therefore MHC diversity is an indicator of population health. I have (1) Isolated exon 2 of the class II gene DQA in Tursiops truncatus in the North Indian River Lagoon (IRL) (n=17), South IRL (n=29) and adjacent Atlantic waters (n=20), (2) assessed genetic variability between groups, (3) developed a method to genotype individuals, (4) typed 11 unique alleles in 66 individuals, (5) detected geographic patterns of diversity between estuarine and coastal individuals (FST=0.1255, p<0.05), (6) found evidence of positive selection centered in the binding pockets P1, P6 and P9 of the peptide binding region (w=2.08), (7) found that patterns of polymorphism did not closely match patterns of diversity in neutral markers, (8) performed a pilot study with Orcinus orca. The initial findings highlight the need for further comparative work and suggest that silent mutations are not neutral. / by Tatiana Ferrer. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
99

Site Fidelity, Associations and Long-Term Bonds of Short-Finned Pilot Whales off the Island of Hawai`i

Mahaffy, Sabre D. 01 January 2012 (has links)
Short-finned pilot whales (Globicephala macrorhynchus) are the most frequently sighted odontocete in a long-term study in Hawaiʹi (representing 23.8% of all odontocete sightings from directed research efforts), yet little has been published on this species in Hawaiian waters. Studies elsewhere have suggested that short-finned pilot whales travel in stable mixed-sex groups composed of strongly associated individuals; however temporal analyses of social structure are lacking. To examine site fidelity, association patterns and temporal relationships, I analyzed data from 267 directed research and opportunistic encounters of short-finned pilot whales off the island of Hawai`i from 2003 through 2007. Sightings occurred year-round. Analysis of sighting depths in relation to effort indicated short-finned pilot whales are strongly associated with the island slope, with no sightings in water >2,700m deep despite effort to ~5,000m. Using only good quality photos, I identified 448 distinctive individuals; of these, 305 (68.1%) were seen more than once and 250 (55.8%) were seen in >1 year. Sighting histories varied from 1-29 sightings per individual (median=3) over the course of the study, suggesting only some individuals exhibit high site-fidelity. Degree of residency was assessed using multi-year site fidelity to the study area; individuals seen ≥5 times in ≥3 years were considered core residents (154 individuals) while individuals who fell below these criteria but that were seen more than once were termed residents (150 individuals) and those seen on a single occasion were termed visitors (142 individuals). Only 71.9% of the whales were linked by association into a single social network, suggesting the possibility of multiple populations using the study area. Individuals demonstrated preferential associations and community division was strongly supported by average-linkage hierarchical cluster analysis of the association data. Nine longitudinally-stable social units composed of key individuals (seen together ≥8 times in ≥4 years) and their constant companions (seen together ≥5 times in ≥3 years) were identified (unit membership 5-16, median=10.5; mean unit association index: 0.62-0.90). Qualitative assignment of age and sex classes to unit members indicated some segregation between adult males and female/calf pairs may occur. Temporal analysis using standardized lagged association rates of individuals grouped in the same encounter produced a best-fit model where dyads gradually disassociated over time while individuals grouped in the same day produced a model where dyads remained in association, suggesting companions not documented during an encounter are likely still present in the study area. Differential patterns of residency and site fidelity were unexpected and may be indicative of multiple populations around the main Hawaiian Islands. Additionally, the presence of a core resident population demonstrating strong, long-term site-fidelity and associations off the island of Hawaiʹi may warrant special management considerations. Evidence of fisheries-related injuries in addition to anthropogenic threats such as high levels of commercial and recreational vessel traffic, targeted tourist activities, and commercial and sports troll fisheries indicate that additional research is needed to evaluate potential threats to this island-associated population.
100

Some aspects of male vervet monkey behaviour

Freeman, Natalie J January 2012 (has links)
The permanent coresidence of males within a troop is unusual but occurs in vervet monkeys. Several hypotheses have been projected to explain the coexistence of male vervets (predation risk, breeding season length) but these hypotheses fall short in explaining the multimale nature of vervet monkeys. In order to determine the explanation for coresiding males, I collected male behavioural data from two troops over the course of nine months. My dataset was divided into two categories, male-male interactions and female-male interactions. The male-male data indicate that breeding season is the most active time for migration, aggressions and wounds. Coalitions were described for the first time, and affiliative interactions between males highlighted coping tactics of males in regards to their coexistence. The female-male data indicate there was little indication for distinct male or female choice for mating. Specifically, olfactory information appears to lower successful copulations of males, and female resistance also decreased successful copulations. Grooming was not a commodity traded for mating access. Male dominance was not correlated with mating success, and females seem to express their preference for sexual partners. The large cohort of males of my troops appears to alter behaviours observed at other sites. The maintenance of male-female associations after breeding season suggests that males may be preparing for next breeding season, and males may co-reside for breeding purposes. / xiii, 123 leaves : ill. maps ; 29 cm

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