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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.
121

Personality in piglets : Is there a difference in personality traits between pigs from different teat order positions?

Sundman, Ann-Sofie January 2011 (has links)
The objective of this study was to determine whether piglets from different positions in the teat order differ inpersonality. Teat order is established within the first days after birth and from that time, piglets basically suckle fromthe same teat pair until weaning. Three piglets from each of 21 litters (n = 63) were chosen for their place in teatorder; one from anterior teats (A), one from middle teats (B), and one from rear teats (C). The piglets were observedduring suckling, undisturbed behaviour, a novel object test and a straw test. A total of 13 behaviours were registered.A significant difference (P < 0.05) between A, B and C piglets was found in the frequency of disputes duringsuckling, where B piglets were most involved in disputes and C piglets least involved, and a tendency (P < 0.1) wasfound in frequency of undisturbed playing and exploration. A piglets played and explored most, and C piglets least.Four interesting components were found with principal component analysis, explaining 62.4 % of the total variation.These represent personality traits tentatively named exploration, playfulness, food interest and straw interest. Therewere no significant differences in personality type between A, B and C piglets although a tendency that A pigletswere most playful and C piglets were least playful was found. Hence, this study suggests that there might be acorrelation between teat order position and personality.
122

Fodertillgång och stereotypa beteenden under natten hos Asiatisk elefant (Elephas maximus)

Olby, Sara January 2011 (has links)
Animals in zoos live in more barren environments than their conspecifics in nature. In nature, elephants spend more than 75 % of the day foraging and have been observed lying down two hours during night. Stereotypies are common in many different species in zoos. Stereotypic behaviors may constitute up to 50 % of the daily activity budget of zoo elephants. Modern zoos try to reduce stereotypic behaviors by means of environmental enrichment. Three elephant cows at Kolmårdens Djurpark were observed during night to map their nocturnal behaviors and see how they changed with feeding enrichment. The elephants were lying down on their sides 25 % of the time observed. With feeding enrichment offered in the morning, the stereotypies was reduced in one individual from 43 % to 13 % (P<0.01) and the foraging was increased in two individuals from 45 % to 80 % (P<0.01) and from 45 % to 64 % (P<0.05). Increased food access increased foraging behavior and as environmental enrichment was able to reduce the stereotypic behaviors in these Asian elephant.
123

The Development and Role of Peripheral Auditory Structures in <i>Otocinclus affinis</i>

Botta, Sri Kiran Kumar Reddy 01 November 2009 (has links)
Loricariidae is a very diverse family of catfishes found primarily in the Amazon River basin. These catfishes have a unique characteristic feature of having fenestrae (holes) in the skull region (compound pterotic bone) adjacent to their bi-lobed swim bladder. Since the swim bladders and the compound pterotic may act as an external ear for hearing in this taxon, I hypothesized that these swim bladders structures have an acoustical functional in the loricariid Otocinclus affinis. In order to understand the development of these structures in O. affinis, I first monitored the ontogeny of the compound pterotic bone by clearing and staining of fish ranging total length from 0.75 to 3.5 cm. the swim bladders and fenestrated compound pterotic bone were developed at early larval stages (by 5.25 mm TL). Second I examined the role of swim bladders in hearing in adult O. affinis, by testing the hearing sensitivity before and after swim bladder deflation. Hearing thresholds were determined electrophysiologically by recording auditory evoked potentials (AEP). Swim bladder deflation increased hearing thresholds by 19 – 23 decibels (dB). I then tested the role of the compound pterotic bone fenestrae in hearing by covering them with a tissue adhesive (n-butyl cyanoacrylate) and recording the hearing thresholds. Covering fenestrae increased hearing thresholds by 4 – 11 dB. Future experiments are required to more precisely determine the acoustical role of these peripheral auditory structures in O. affinis.
124

Social behaviour responses in red junglefowl (Gallus gallus) selected for tameness

Ericsson, Maria January 2010 (has links)
Historically during domestication of animals, tameness towards humans was likely the most desired trait and therefore bred on. The red junglefowl (Gallus gallus) is the wild progenitor of all domestic chicken breeds and earlier studies present clear morphological, physiological and behavioural differences between domesticated breeds and the non-domesticated red junglefowl. These changes may be the result of altered gene expression - pleiotropy or linked genes. The aim of this thesis was to evaluate (1) effects of tameness selection on social behaviour towards conspecifics and (2) social behaviour differences between the sexes. Two generations of red junglefowl, P0 and its offspring F1, were studied. Both generations were divided into three selection lines (tame, intermediate or fearful), depending on their results in a fear of humans test.  A novel type of social reinstatement test was set up, containing a non-social area without stimulus, and a social area containing a mirror serving as stimulus animals. The social and aggressive behaviours performed towards the mirror were recorded, so was the time spent in the social versus non-social part. An undisturbed behaviour test was performed, as well as a standardized social reinstatement test. The P0-females performed significantly more social behaviour (p=0.008) at 26 weeks than males in the mirror test, and females also displayed significantly more social (p=0.04) and agonistic behaviour (p&lt;0.001) than males in the undisturbed behaviour test. The social reinstatement test displayed a significant effect between the selection lines with regards to sociality. This suggests that there are immediate selection responses in early domestication.
125

Foraging and exploratory behaviour in Red Junglefowl (Gallus gallus) selected for fear of humans

Walett, Emma January 2010 (has links)
Domestication is a process in which animals become adapted to a life among humans by means of selection. A reduced fear of humans is probably one of the first aims of selection, intentionally or unintentionally. Animals that have undergone the process of domestication have a different appearance than animals in the wild (domestic phenotype) and behave in a different way towards humans. In this study I have looked at foraging and explorative behaviours in an unselected parental generation of red junglefowl and their offspring. The parental generation were bred in three lines, a high line, with birds displaying a strong fear of humans, an intermediate line, birds showing a modest fear, and one low line, with birds performing a more tame behaviour towards humans. I presented the birds with three different feeding alternatives, familiar chicken food, meal worms camouflaged with wood shavings and just wood shavings. I counted number of pecks in the different food options, number of changes between sites and how many sites a bird visited. The results show that females of both generations were more explorative than males, by pecking more in cups of meal worms hidden in wood shavings whereas the males pecked more in cups containing chicken food. Females also moved around more in the arena. Results from the first selected generation show significant differences between the selection lines among the females, with females from the high and low groups being the most explorative.
126

Accessible theatre : the application of human ethology and innate neurobiological systems to full-masked devised theatre practice

Cook, Sally January 2012 (has links)
This thesis is concerned with the challenges of devising a full-masked theatre performance that is largely accessible to audiences of every age, social background and culture. The contribution to original knowledge is in the study's examination of the relationship between the devising processes of a full-masked performance, neurobiology, human ethology and the accessibility of audience reception (Bennett, 1994). The thesis addresses the concept of accessibility by taking a phenomenological approach to devising and audience reception, with particular focus on the role of neurobiological systems and structures, in particular the mirror neuron system, the pleasure-reward system, and pattern recognition systems, in the communication and reception of performance meaning (McConachie, 2008). The research is framed by the concept of a universal theatrical language proposed by practitioners Peter Brook and Tadeshi Suzuki, which has the potential to connect people at the deepest levels of their humanity (Pavis, 1996: 6). Practical approaches adopted in the research are informed and supported by anthropological and human ethological claims of universality (Ekman, 1975; Brown, 1991; Eibl-Eibesfeldt; 2007 [1989]; Schmitt et al. 1997). This thesis theorizes that human beings possess innate neurobiological systems that interact with culturally specific concepts, conditions and knowledge in such a way that when deployed appropriately, these innate neurobiological systems can be a platform for human cognition and for the designing of performances accessible to an audience of different ages, social backgrounds and cultures. It also proposes that innate neurobiological systems create a universal framework that makes it possible for the said broad-based audience to read and receive a performance using similar codes of cognition and aesthetic reference irrespective of age, social and cultural backgrounds. The research process led to the creation of an original full-masked theatrical performance and eighteen performances of this piece were given to different audiences in a range of venues and locations in Northamptonshire. Qualitative and quantitative data analysis of how the various audiences received the performance suggest that the devising methods employed did contribute to making the performance accessible to an audience with a broader constituency than theaters normally envision (Pitts-Walker, 1994: 9-10). This research enables practitioners for whom a wide audience and accessibility are an explicit focus to adopt devising approaches that will help to achieve the desired wide-ranging reception and accessibility in mixed audiences irrespective of race, age, gender and culture.
127

The relationship between behaviour and metabolic rate of juvenile Brown trout Salmo trutta / Länken mellan bettende och ämnesomsättning hos bäcköring Salmo trutta

Bengtson, Johanna January 2009 (has links)
In salmonids, the decision to migrate or remain resident is influenced by the status, and hence condition, of individuals. Status has been suggested to arise from the temperament of fish. In this study the links between standard metabolic rate and the levels of aggressiveness and shy/boldness were examined for 0+, hatchery-raised brown trout (Salmo trutta). I hypothesized, from the results of earlier studies (Cutts et al., 1998; Yamamoto et al., 1998), that high metabolic rates (MR) would be positively correlated to levels of aggression and boldness. The study was conducted in 200 L aquaria in which aggressiveness was measured by allowing each fish to interact with a mirror image of itself, and shy/boldness was tested by measuring the amount of time a fish used before exploring a new area. Standard metabolic rate was measured in a flow-through respirometer. In contrast to my expectations, there was no correlation between the different behavioural measures and the metabolic rate of fish. Also, no correlation between boldness and aggressiveness of fish was found. In additional testing aggressiveness correlated positively with the condition of fish (in coherence with Harwood et al., 2003) but, contrary to earlier studies (Överli et al., 2004; Schjolden &amp; Winberg, 2007), not with the speed of acclimatization. The difference in results between this test and earlier studies, concerning the degree of correlation between MR and aggressiveness, suggests that the strength of this link differs between species of salmonids. Also, it may suggest changeability in the MR – behaviour link in different environments. Last, the status and condition of individuals cannot be unambiguously explained by temperament alone, but arise from a wider array of physiological and environmental factors.
128

Learning with ALiCE II

Lockery, Daniel Alexander 14 September 2007 (has links)
The problem considered in this thesis is the development of an autonomous prototype robot capable of gathering sensory information from its environment allowing it to provide feedback on the condition of specific targets to aid in maintenance of hydro equipment. The context for the solution to this problem is based on the power grid environment operated by the local hydro utility. The intent is to monitor power line structures by travelling along skywire located at the top of towers, providing a view of everything beneath it including, for example, insulators, conductors, and towers. The contribution of this thesis is a novel robot design with the potential to prevent hazardous situations and the use of rough coverage feedback modified reinforcement learning algorithms to establish behaviours.
129

Factors Influencing Web Tenure in a Tropical Spider and Comparison between Forest and Non-forest Habitats

Barraza, Daniella R 01 January 2012 (has links)
Webs are fundamental to the ecology of Nephila clavipes, the golden orb-weaver spider, because they serve as sites for prey capture, reproduction, competition, predation, and parasitism. In addition to the presence of the female N. clavipes, males and kleptoparasites reside on the web in varying numbers. Webs are also found in clusters with conspecific females. Web site selection and length of web tenure is a behavioral decision vital to the spider’s fitness and the ecology of her species. I conducted a field census to quantify these factors and analyze their influence on web tenure, compare web ecology between a forest and non-forest habitat, as well as explain the significance of N. clavipes’ web as central to many interactions. Web tenure, as well, was influenced differently by the factors between both environments. In the forest habitat, increase in prey capture rate decreased web tenure and inclusion in cluster increased web tenure. In the non-forest habitat, only increase in spider size was related to increased web tenure. There were significant differences between the two habitats in the sizes of the female spider and quantity of males and kleptoparasites. Results also showed that spider size influenced quantity of males and web diameter influenced quantity of kleptoparasites. Explanation of these results can be attributed to the complex relationships among the variables and the consequences of living in habitats impacted by human occupation.
130

Reinforcement learning in biologically-inspired collective robotics: a rough set approach

Henry, Christopher 19 September 2006 (has links)
This thesis presents a rough set approach to reinforcement learning. This is made possible by considering behaviour patterns of learning agents in the context of approximation spaces. Rough set theory introduced by Zdzisław Pawlak in the early 1980s provides a ground for deriving pattern-based rewards within approximation spaces. Learning can be considered episodic. The framework provided by an approximation space makes it possible to derive pattern-based reference rewards at the end of each episode. Reference rewards provide a standard for reinforcement comparison as well as the actor-critic method of reinforcement learning. In addition, approximation spaces provide a basis for deriving episodic weights that provide a basis for a new form of off-policy Monte Carlo learning control method. A number of conventional and pattern-based reinforcement learning methods are investigated in this thesis. In addition, this thesis introduces two learning environments used to compare the algorithms. The first is a Monocular Vision System used to track a moving target. The second is an artificial ecosystem testbed that makes it possible to study swarm behaviour by collections of biologically-inspired bots. The simulated ecosystem has an ethological basis inspired by the work of Niko Tinbergen, who introduced in the 1960s methods of observing and explaining the behaviour of biological organisms that carry over into the study of the behaviour of interacting robotic devices that cooperate to survive and to carry out highly specialized tasks. Agent behaviour during each episode is recorded in a decision table called an ethogram, which records features such as states, proximate causes, responses (actions), action preferences, rewards and decisions (actions chosen and actions rejected). At all times an agent follows a policy that maps perceived states of the environment to actions. The goal of the learning algorithms is to find an optimal policy in a non-stationary environment. The results of the learning experiments with seven forms of reinforcement learning are given. The contribution of this thesis is a comprehensive introduction to a pattern-based evaluation of behaviour during reinforcement learning using approximation spaces.

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