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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.
1

The functions of agonistic interaction, social dominance and display in a winter population of the great tit, Parus major L

Wilson, Jeremy David January 1989 (has links)
No description available.
2

Aggression, impulsive choice and serotonin in male golden hamsters

Cervantes, Martha Catalina 16 September 2010 (has links)
Aggression studies in laboratory animals have largely focused on natural species-specific forms of aggression that poorly reflect pathological types of aggression in humans. The primary goal of this dissertation was to identify and characterize a subtype of aggression in support for a congenital animal model of reactive/impulsive-aggression in humans. Experiments using novel second-by-second analyses to investigate for individual differences in aggression and impulsive choice showed detailed quantitative and qualitative differences, and identified a convergence of behaviors to one distinct impulsive-aggressive profile in high-attack frequency (HAF) hamsters. As aggression and impulsivity widely implicate the serotonin (5HT) system, and previous studies have similarly characterized the neural control of aggression in hamsters, it was hypothesized that impulsive-aggression in HAF individuals was associated to common neurobiology. While 5HT does play a role, immunocytochemical experiments and pharmacological manipulations showed a distinct neurobiological profile of decreased 5HT availability, increased densities of 5HT1A and 5HT3 receptor subtypes, and drastically differential and opposite phenotypic-dependent reactivity to 5HT3 receptor blockade. Moreover, the current studies also showed that while 5HT3 receptor activity has broad effects, attenuating all behavioral aspects of the impulsive-aggressive phenotype (i.e. aggression, repetitiveness, fragmentation, and impulsive choice), 5HT1A receptor activity seems to have more limited effects. Additional retrospective studies investigated developmental and etiological differences between the phenotypes. HAF adults were associated with low agonistic activity in early puberty and an early emergence of impulsivity-related characteristics. These data indicate a differential developmental trajectory of behavior and accelerated maturation, consisting of a lack of play fighting during early puberty. The HAF phenotype was additionally associated with paternal, but not maternal influence, suggesting male genetic contribution. Together, these data support a congenital animal model that better reflects reactive forms of aggression in humans through the behavioral, neurobiological, and developmental characterization of HAF hamsters described herein. These data have pre-clinical and clinical significance and can be applied to diagnostic and preventative measures, as they illustrate the importance of distinguishing predictions about extreme fringe populations from that of normal populations, point towards more specific pharmacological therapeutic applications, identify early predictive behaviors of impulsive-aggression, and suggest heritability. / text
3

Human interaction with Formosan macaques¡]Macaca cyclopis¡^ and the human impacts on Mt. Longevity

Kao, Chien-ching 02 June 2004 (has links)
The purpose of this study was to analyze the interactions of visitors and Formosan macaques (Macaca cyclopis) at the Mt. Longevity. Data on the attitudes of visitors were collected by using questionnaires covering topics such as purpose, frequency and opinions of visitors. Scan samplings, agonistic behavior samplings and focal samplings were used as observational methods to record the agonistic behaviors of monkeys. The study also analyzed patterns of human-monkey interactions that recorded through ad libitum samplings, including visitor participation that influenced agonistic behaviors among the monkeys. Statistical analyses were used to analyze various factors that influenced agonistic frequency and patterns. The agonistic behaviors in dyads during food provision tests were used to establish their rank relationships and dominance styles. Mt Longevity is a major recreational site in Kaohsiung city; the human pressure on Mt. Longevity was high and the tourist numbers were estimated as 6175 individuals ( ¡Ó 119, n = 10) in holidays and 3490 individuals ( ¡Ó 68, n = 10) in weekdays (between 08:00 to 18:00 hrs). The vegetation cover was apparently reduced above 60% in 16 recreational sites surveyed. The tourist numbers appeared to exceeding the carrying capacity of Mt. Longevity. The frequencies of human-monkey interaction were influenced by the number of monkeys and concentrated during the afternoons; the average frequency was 9.3 times / hr in holiday and 3.3 times / hr in weekday. The average frequency of tourists provisioned for monkeys was 0.59 times / hr ( ¡Ó 17.2, n = 131). An overall ratio of 17.5 : 1 between human-initiated and monkey-initiated interaction behaviors was found. Pass and eye contact accounted for over 67% of these interactions, and adult monkeys participated in human-monkey interaction more than the rest of the age / sex classes. During the conflict between human and macaques, most visitors used sticks or hands / legs to drive adult males away (63.5%). The average daily activities of Formosan macaques were: 37.7% inactive, 24.6% moving, 24.5% affiliation, eating / foraging 9.5% and agonistic behavior 2.6%. Frequencies of monkey aggressive behaviors increased along with increasing individuals of monkeys, and frequencies of their body aggressions and aggressions were higher during provision than without human disturbance. Open mouth threat was the most frequent aggressive behavior expressed by the monkeys (60.0%), while fleeing (37.0%) and squealing (36.0%) were the most common submissive behaviors. Agonistic initiators were mostly adult females (41.9%) and males (40.4%) and agonistic reactors were mostly juveniles (44.6%) and adult females (32.6%). Monkey contest was only 2.8% - 3.9% of total aggressive behaviors and the study revealed that the dominance style of Formosan macaques was despotic social system. The frequency of aggressive behavior of adult males (1.3 ¡Ó 2.1 times / 20min, n = 14) was 2.6 times in average to that of adult females (0.5 ¡Ó 0.9 times / 20min, n = 17). It varied significantly among different adult males and it was higher in mating seasons than the non-mating seasons (p<0.05). However, the frequencies of aggressive behavior of adult females were similar between seasons and among ranks (low, middle and high) but the frequency of submissive behaviors was higher in low rank adult females than that of high rank ones (p<0.05). Adult male and female Formosan macaques had a similar dominance style (aggression, avoidance, ignoring, undecided, AAD pattern and NNI pattern) in food tests; adult males showed more frequent aggression toward adult males than to adult females and juveniles. The individuals who showed open mouth threat had a success rate of getting food for over 50%.
4

Context and Functions of Agonistic Calls in Formosan Macaques

Chuang, Chih-wen 02 September 2004 (has links)
Abstract This study analyzed the contexts of three types of agonistic calls (Growl, Threat rattle, Vibrato growl) in Formosan macaques and their responses to predators and alarm calls at Mt. Longevity. Under natural condition, 112 five-minute scan samplings and 100 twenty-minute behavior samplings were collected to record agonistic behaviors and agonistic calls of macaques. In addition, 11 dog-presence tests and 102 playback experiments were successfully conducted from January 2003 to April 2004. Of 385 agonistic events, 61.8% comprise of vocal bouts contained units belonging to single type of agonistic calls, and 31.8% bouts were mixed units contained more than one type of agonistic calls. Among these three single types of agonistic calls, Vibrato growl was used most frequently during conspecific interactions (44.3%); Threat rattle was used toward human (51.7%) and dogs (94.4%). During intraspecies conflicts of macaques, the vocal rates of three single type agonistic calls decreased from adult males, adult females and juveniles to infants. The average units per bout of Growl was higher than that of Threat rattle and Vibrato growl (p<0.0002). However, the agonistic interactions explain the different functions of the three types of agonistic calls. Growl was frequently accomplished with chase of callers (45.6%), while flee was usually expressed by receivers (57.9%). When monkeys uttered Threat rattle or Vibrato growl, open mouth threat was the most frequent behavior expressed by callers (80.5% and 73.1%), while evade was most frequent behavior expressed by receivers (43.9% and 31.9%). Growl conveyed messages about intense callers and contexts, and receivers avoided damage through fleeing. These results support Smith (1981) hypothesis referential signal carry information about external objects, contexts or a caller internal state as reflected in the probability of its subsequent behavior pattern. Receivers are able to attribute a certain meaning and express appropriate responses by the combination of signal structure and the context in which they are exposed the call. Six different acoustic features of alarm calls existed between adult males and juvenile males. Alarm calls from Juveniles have higher Maximal, Median and Modulation Fundamental Frequencies than from adult males (p<0.0001). But alarm calls from juveniles have lower Highest Frequency, Total Range of Frequency and Duration of each Unit than from adult males (p<0.005). The results support current theory that the duration and fundamental frequency reflect body size. In the playback experiments, macaques responded stronger to alarm calls from adult males than from juvenile males (p<0.0001). The average response score of macaques toward alarm calls from playback experiments was highest from infants, followed by juveniles, adult females and adult males. Adult macaques often responded to playbacks by looking in the direction of the loudspeaker. Juveniles and infants most often responded to playback calls by escape and startle. In playback experiments of alarm calls from adult males, F troop had significant different responses in three different places, strongest in the unfamiliar place (p<0.0001). The presents of dog elicited macaques with stronger responses than playback of dog barks (p<0.0001).
5

Effects of serotonin on the agonistic behavior in paradise fish (Macropodus opercularis Linnaeus)

Chiu, Kuo-Hsun 07 December 2002 (has links)
Animal agonistic behaviors, including threat, combat, submission and chase, are complex responses to experimental stimuli. Animal behaviors are regulated by the central nervous system. In the central nervous system, the biogenic amine serotonin has been thought to serve important roles in animal aggression (including fish), but it¡¦s not clear if serotonin affects threatening and fighting differently. This study took experimental approaches to examine the effects of this neurotransmitter on threatening and fighting in a paradise-fish model in which the complex agonistic behavior is well characterized. Treatments with serotonin synthesis precursor tryptophan (0.125mg/g) to one of the two contestants had insignificant effects on threatening or fighting while synthesis blocker p-Chlorophenylalanine (PCPA) (0.3mg/g) decreased threatening time and occurrences of head-tail display. When these drugs were added to both contestants, tryptophan reduced all agonistic behavioral patterns displays, and PCPA decreased threatening time and head-tail display. In addition to changes in behavioral patterns, tryptophan led the fish to be attacked. In contrast, PCPA led the injected fish to actively attack its opponent. However, tryptophan and PCPA had no effect on social status in parasise fish. I suggest that agonistic responses and the initial fighting decision in a paradise fish are affected not only by level of its serotonin, but also by the behavioral responses of its opponent. And the establishment of outcome of encounter is affected more by the environmental stimuli than the serotonin level.
6

The development of agonistic behavior in male golden hamsters : from behavior to brain

Taravosh-Lahn, Kereshmeh 06 September 2012 (has links)
In male golden hamsters, puberty is marked by dramatic changes in agonistic behavior. Attack frequency gradually decreases as agonistic behavior evolves from play fighting to adult aggression. Attack types change as targets of attack mature from play fighting to adult attacks. In adult hamsters, serotonin plays an inhibitory role in aggression. Thus, the decline in attack frequency during puberty could be associated with an up-regulation of the activity of the serotonergic system. In adults, acute Fluoxetine treatment inhibited aggressive behavior at all doses. In juveniles, only the highest dose reduced attack frequency. Interestingly, juveniles treated with the lowest dose showed an increase in aggressive behavior. Attack type was also affected as treatment with Fluoxetine accelerated the maturation of attack targets. This same effect had been observed in previous studies in response to chronic social stress and dexamethasone treatment. Consequently, the role of cortisol on the development of the serotonergic system was also investigated. Furthermore, the density of serotonin innervation in the anterior hypothalamus and medial amygdala was found to be higher in adults than juveniles and consistent with the inhibition of attacks by the high dose of Fluoxetine. However, the differential effects of Fluoxetine at the lower doses were investigated through analysis of different serotonin receptor subtypes. In adult hamsters, aggression can be facilitated by activation of 5-HT₃ receptors and inhibited by 5-HT[subscript 1A] receptors. During puberty, the density of immunoreactive 5-HT1A receptors increased in the anterior hypothalamus and medial amydala while 5-HT₃ receptor immunoreactivity did not change. Thus, it is possible that in these areas the ratio of 5-HT₃ to 5-HT[subscript 1A] receptors decreases during puberty. This change is consistent with the decline in the frequency of offensive responses during puberty. The functionality of 5-HT[subscript 1A] and 5-HT₃ receptors on offensive aggression in juveniles was tested via peripheral injections of a 5-HT[subscript 1A] receptor agonist and a 5-HT₃ receptors antagonist. At the high dose, both drug treatments inhibited attack frequency and attack repetition. Together, these data examine the role of the serotonergic system on the development of agonistic behavior. / text
7

The development fo agonistic behavior in male golden hamsters from behavior to brain /

Taravosh-Lahn, Kereshmeh. January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
8

Dealing with conflicting visions of the past : the case of European memory

Toth, Mano Gabor January 2017 (has links)
The aim of my dissertation is to understand and critically evaluate how the idea of European memory has been conceptualised by different actors at the European level and to develop a novel, pluralist conception. Attempting to ground European integration and the attachment to Europe in historical narratives has become increasingly important for the EU since the loss of its main ideological “Other,” the Soviet Union. The projects adopted in this vein often have the explicit goal to address the “legitimacy problem” and the “democratic deficit” by promoting European identity. In the EU politics-academia nexus, where most of the related debate takes place, the buzzword “European memory” has become very fashionable in the last decade. The idea has been conceptualised in a variety of ways, but most of these are characterised by teleological frameworks and problem-solving thinking. In my dissertation, I examine and critically evaluate how the idea of European memory has been conceptualised by different actors at the European level, and I develop a novel conception based on radical democratic theory. I analyse how the concept of European memory has been used in different European institutions and cultural projects (such as the European Parliament and the House of European History), and I critically reflect on these practices. In my pluralist vision of the European mythical space, conflicting visions of the past are not regarded as an anomaly that needs to be overcome by rational consensus or as an asset that can be harvested in order to bolster the legitimacy of certain political bodies. This vision takes difference to be an inevitable condition of social life and it argues that, instead of trying to resolve conflicting interpretations of the past, social difference should be embraced and the nature of conflict should be changed so that antagonistic relationships can become agonistic ones through dialogue and education. On the one hand, my dissertation contributes to the field of memory studies with a comprehensive pluralist approach to myth. On the other hand, I contribute to European studies, and more specifically to the academic discussion about European memory, when I contextualise this theory of myth in the contemporary European politics of the past.
9

Agonistic behaviour of the black-headed gull, Larus ridibundus

Manley, G. H. January 1960 (has links)
No description available.
10

Comparison of Agonistic Behaviors by analysis of activity in two groups of Confined Primates, Mandrills (Mandrillus sphinx) and Ring-tailed Lemurs (Lemur catta)

Sibley, Taryn Ann January 2004 (has links)
Thesis advisor: David Krauss / Behavior in a confined group of mandrills (Mandrillus sphinx) and a confined group of ring tailed lemurs (Lemur catta) were analyzed to reveal any significant differences in agonistic behaviors and to assess the varying stress levels between individuals. I predicted that the activity rate of the individuals would determine the amount of agonistic behavior demonstrated, specifically that more active individuals would be more frequently performing agonistic behaviors than those who were less active. The mandrills as a whole exhibited a higher activity rate than the lemurs, and the proportion of time spent exhibiting agonistic behaviors was also higher, as expected. These results suggest that the mandrill population is under more stress than the lemurs. Differences in the age makeup of these groups may partially explain the behavioral differences that occurred: the mandrills' group included a juvenile who was considerably more active than his parents while all three lemurs observed were adults. Differences in the size of the exhibit may also explain the differences as the exhibit for the mandrills was smaller than that of the lemurs, while the mandrills were more than triple the lemurs' size. This analysis supports earlier studies: that primate behavior is influenced strongly by their environment and its cohabitants. / Thesis (BS) — Boston College, 2004. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Biology. / Discipline: College Honors Program.

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