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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.
11

Understanding of human communicative motives in domestic dogs

Pettersson, Helene January 2009 (has links)
<p>I investigated the understanding of human communicative motives in domestic dogs. Dogs use human communicative cues, like the pointing gesture when searching for hidden food, but it is uncertain how dogs interpret human communication. 32 dogs were presented with two communicative contexts in an object choice task experimental design. In a cooperative context the experimenter informed the subject where food was hidden by pointing and giving a verbal indication. In a competitive context the experimenter held out her arm towards the correct location in a stop gesture and firmly said no. To be successful in the competitive context the subject had to understand the experimenters communicative motive and make an inference from the prohibition (i.e. she would only prohibit it if there was something good there). The average correct choices were compared between the conditions. The dogs successfully followed the cooperative communication. They showed a trend towards choosing the baited cup in the competitive condition. A second study tested if the stop gesture affected the dogs’ choice, since it is not known how dogs interpret gestures. The pointing cue was now presented with the prohibiting command and the stop gesture was presented with the cooperative verbal cue. The dogs used the cooperative communication but did not understand the competitive context. A difference between the contexts was found. The dogs did not differentiate between the gestures. In conclusion dogs do not make inferences from competitive communication or prohibition but are specialized in utilizing cooperative communication</p>
12

Do enclosure characteristics affect anti-predator behaviour in the European bison (<em>Bison bonasus</em>)?

Hofling, Annika January 2009 (has links)
<p>Animals raised in captivity often fail to express appropriate anti-predator behaviour when reintroduced into the wild. The European bison (<em>Bison bonasus</em>) is a species that was close to extinction in the early 20<sup>th </sup>century but was saved in the last moment by intense captive breeding and subsequent reintroduction into the wild. In this study, seven groups of European bison living in different locations in Sweden were studied to investigate whether there was any difference in the anti-predator behaviour depending on the type of enclosure they were kept in. Olfactory and auditory stimuli from moose, as a control, and from two predators, wolf and bear, and visual stimulus (silhouette of a wolf) were presented to the animals and their response to them and behaviour following presentation were analysed. The results showed that European bison kept in barren enclosures responded stronger to auditory stimuli than those that were kept in naturalistic enclosures. The results further showed that the animals had a stronger response to the visual stimulus than to the auditory stimuli. The animals changed their behaviour after stimuli presentations compared to a pre-test baseline. They moved, stood still and ate for a significantly longer period of time and they rested for a shorter period of time after being presented olfactory, auditory and visual stimuli than during pre-test baseline.</p>
13

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

Walett, Emma January 2010 (has links)
<p>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.</p>
14

Social behaviour responses in red junglefowl (<em>Gallus gallus</em>) selected for tameness

Ericsson, Maria January 2010 (has links)
<p>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<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.</p>
15

Zero-order manipulation task to obtain a food reward in Colombian black spider monkeys (<em>Ateles fusciceps rufiventris</em>) kept in a zoo

Högberg, Sofia January 2010 (has links)
<p>Spider monkeys (<em>Ateles</em> sp.) are common in zoological parks, but rare in scientific publications. Studies on tool use in primates have mostly focused on impressive tool users such as chimpanzees. Spider monkeys fulfill several criteria that are known to be associated with tool use. To be able to give an appropriate environment and enrichment for spider monkeys in captivity more knowledge is needed about their cognitive abilities. In this study we wanted to see if five male spider monkeys kept in a zoo could learn to use tools to reach a reward. Experiment 1 examined the subjects’ ability to learn to use a stick-tool to extract honey from a tube and experiment 2 their ability to learn to use a rake-tool to reach a reward. Each experiment consisted of three parts; A – monkeys got tools and treat next to each other; B – monkeys were shown how to use tool to get treat by a keeper and then got tools and treats next to each other; C – monkeys got tools and treats so they just could pull out the tool and get the treat. In both experiments at least two different spider monkeys succeeded with the zero-order manipulation task to pull out the tool and get treat in part C. Longer studies need to be conducted to be able to say if spider monkeys are able to learn a more complex tool using behavior as needed in part A and B.</p>
16

Living with males : benefits and costs to females of resident males in <em>Colobus vellerosus</em>

Hedlund, Johanna S. U. January 2009 (has links)
<p>Only in primates is permanent male-female association the most widespread social structure of all. The continuous presence of resident males in the social group can have significant impacts on female fitness, both in forms of costs and benefits. In this study I investigate particular short-term benefits and costs of resident males to females in a population of ursine colobus (<em>Colobus vellerosus</em>). I hypothesise that for females permanent association with males result in certain benefits and certain costs, exceeding those provided or imposed by other females. The results indicate that female derive greater benefits from males than from females during intergroup encounters and in the form of vigilance since males were the main participants in intergroup encounter and were more vigilant than females. I could not confirm any type of behaviour employed by resident males that is costly to females. However, the rarity and subtleness of some costly male behaviours imply that more data is needed before making a conclusion on their absence or occurrence in this population and I purpose that herding behaviour could occur at my study site. Moreover, multi-male groups (MM-groups) showed higher rates of vigilance than single-male groups (SM-groups) and had a tendency to experiencing fewer intergroup encounters than SM-groups. I interpret the former as a result of the demanding social conditions in the MM-groups. The latter indicate that females may benefit from MM-group living through a decrease in intergroup encounters.</p>
17

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

Bengtson, Johanna January 2009 (has links)
<p></p><p>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 (<em>Salmo trutta</em>). I hypothesized, from the results of earlier studies (Cutts <em>et al</em>., 1998; Yamamoto <em>et al</em>., 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 <em>et al</em>., 2003) but, contrary to earlier studies (Överli <em>et al.,</em> 2004; Schjolden & 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.</p><p> </p>
18

Relations between metabolic rate, migration and behaviour in Atlantic salmon (<em>Salmo salar</em>) and brown trout (<em>Salmo trutta</em>)

Lans, Linnea January 2010 (has links)
<p> </p><p>ABSTRACT</p><p> </p><p>Migration is common among populations of brown trout (Salmo trutta) and Atlantic salmon (Salmo salar). However, not all individuals in the same population migrate, a phenomenon referred to as partial migration. The aim of this thesis was to investigate if an individual’s behaviour and metabolic rate influences its decision to migrate and how such knowledge may be used when trying to produce hatchery-raised smolts with as high a proportion of migrating individuals as possible. In paper I the influence of reduced food ration on the proportion and swimming speed of migrating brown trout and Atlantic salmon smolts was investigated. Furthermore, the standard metabolic rate (SMR) of migrating and non-migrating individuals was compared. In paper II, a laboratory experiment, SMR was correlated to the behaviour of individual brown trout and Atlantic salmon. Dominant fish of both species had a higher SMR than subordinates (paper II). In addition, migrant brown trout had a higher SMR than non-migrant trout when given a normal food ration, whereas no difference in SMR between migrating and non-migrating salmon could be seen (paper I). When administered low food rations, smolts of both species migrated faster than smolts given a normal food ration, and the proportion of migrating smolts was higher for salmon given less food when the size difference for smolts from the two feeding regimes was large (paper I). Other factors that influenced migration speed were the degree of smolt development and water temperature (paper I). SMR was not correlated with aggressiveness, or with different measurements of boldness. Moreover, aggression and boldness were not correlated with each other (paper II). Trout showed a higher level of aggressiveness and acclimated more rapidly to laboratory conditions than salmon (paper II). In summary, there was no support for the existence of coping styles in migratory Atlantic salmon and brown trout. Instead, metabolic rates were related to both migratory behaviour and social status. Furthermore, an individual’s decision to migrate was influenced by ration size.</p>
19

Relations between metabolic rate, migration and behaviour in Atlantic salmon (Salmo salar) and brown trout (Salmo trutta)

Lans, Linnea January 2010 (has links)
ABSTRACT   Migration is common among populations of brown trout (Salmo trutta) and Atlantic salmon (Salmo salar). However, not all individuals in the same population migrate, a phenomenon referred to as partial migration. The aim of this thesis was to investigate if an individual’s behaviour and metabolic rate influences its decision to migrate and how such knowledge may be used when trying to produce hatchery-raised smolts with as high a proportion of migrating individuals as possible. In paper I the influence of reduced food ration on the proportion and swimming speed of migrating brown trout and Atlantic salmon smolts was investigated. Furthermore, the standard metabolic rate (SMR) of migrating and non-migrating individuals was compared. In paper II, a laboratory experiment, SMR was correlated to the behaviour of individual brown trout and Atlantic salmon. Dominant fish of both species had a higher SMR than subordinates (paper II). In addition, migrant brown trout had a higher SMR than non-migrant trout when given a normal food ration, whereas no difference in SMR between migrating and non-migrating salmon could be seen (paper I). When administered low food rations, smolts of both species migrated faster than smolts given a normal food ration, and the proportion of migrating smolts was higher for salmon given less food when the size difference for smolts from the two feeding regimes was large (paper I). Other factors that influenced migration speed were the degree of smolt development and water temperature (paper I). SMR was not correlated with aggressiveness, or with different measurements of boldness. Moreover, aggression and boldness were not correlated with each other (paper II). Trout showed a higher level of aggressiveness and acclimated more rapidly to laboratory conditions than salmon (paper II). In summary, there was no support for the existence of coping styles in migratory Atlantic salmon and brown trout. Instead, metabolic rates were related to both migratory behaviour and social status. Furthermore, an individual’s decision to migrate was influenced by ration size.
20

Zero-order manipulation task to obtain a food reward in Colombian black spider monkeys (Ateles fusciceps rufiventris) kept in a zoo

Högberg, Sofia January 2010 (has links)
Spider monkeys (Ateles sp.) are common in zoological parks, but rare in scientific publications. Studies on tool use in primates have mostly focused on impressive tool users such as chimpanzees. Spider monkeys fulfill several criteria that are known to be associated with tool use. To be able to give an appropriate environment and enrichment for spider monkeys in captivity more knowledge is needed about their cognitive abilities. In this study we wanted to see if five male spider monkeys kept in a zoo could learn to use tools to reach a reward. Experiment 1 examined the subjects’ ability to learn to use a stick-tool to extract honey from a tube and experiment 2 their ability to learn to use a rake-tool to reach a reward. Each experiment consisted of three parts; A – monkeys got tools and treat next to each other; B – monkeys were shown how to use tool to get treat by a keeper and then got tools and treats next to each other; C – monkeys got tools and treats so they just could pull out the tool and get the treat. In both experiments at least two different spider monkeys succeeded with the zero-order manipulation task to pull out the tool and get treat in part C. Longer studies need to be conducted to be able to say if spider monkeys are able to learn a more complex tool using behavior as needed in part A and B.

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