Background: Chlamydia screening is an international strategy used to reduce rates of infection in a target population. This thesis set out to explore the behaviour of young people against the principles of this government strategy for infection control and self-empowerment. The work was set in County Durham and Darlington where I led a service for improved awareness and screening for Chlamydia for young people aged 15 – 24 years. Aims: This research was based on interviews with Chlamydia screening service users in order to understand the factors that influenced their risk taking behaviours and to generate theory for public health practice. An analysis of outcomes from a large sample of over 20,000 subjects and observations of young people in settings where Chlamydia testing and advice was available gave context and background to this study. Findings Chlamydia screening was used as a strategy to offset risk taking that enabled young people to continue behaviours that they valued. This finding is a new and unexpected contribution to Chlamydia screening literature, and also supports the developing theory of edgework. Knowledge and awareness of Chlamydia did not change as a result of screening activities, and this did not have a major influence on preventative behaviour. The national messages that one in 10 young people are infected, and that infection is easily detected and managed, was interpreted by some that nine in 10 young people were not infected, and that this was not a significant health threat. Incentives were found to significantly increase screening uptake although this did not lead to a change in risk taking. There was an increased likelihood to have sex with the perception of knowing a partner, although this was not necessarily based upon factual information. Most participants demonstrated lethal patterns of alcohol consumption that commonly led to sexual encounters and all those who stated that they were aware of safe drinking limits demonstrated lethal patterns of alcohol consumption. All participants with a positive test result had a negative result within the previous year suggesting no change in risk taking following screening, and although all participants said that they would modify their behaviour in the future, when they were probed all stated that this would not happen giving reasons such failure to moderate alcohol use. Conclusion: These findings led me to conclude that risk taking in relation to health and potential disease is a normal process in the development of young people. Young people value risk taking activities for promoting self-identity and supporting emotional and social well-being. Public health interventions need to consider the developmental needs of young people using an asset based approach in order to provide interventions that address the causes of risk taking behaviours.

Risk is inherent in many social and economic decisions, such as the choice of pathway in secondary school, the choice of major at university, job decisions, health-related behaviour, marriage, parenthood, migration and the allocation of financial assets. Investigating the determinants of attitudes towards risk is therefore essential to fully understand how people make such decisions. Recent research has shown that individual risk attitudes are not immutable personality traits, but are influenced by external factors with the potential to change them in more or less enduring ways, such as the characteristics of the environment, emotional states, life experiences such as poverty, job loss or violence, and social relationships. This thesis studies external factors that play a role in shaping risk attitudes. Specifically, it focuses on two important environmental factors: social relationships and the incentive structure that individuals face (e.g., competition or teamwork). It is composed of three chapters. Each chapter of the thesis presents the results of a different laboratory experiment, in which individual risk behaviour is always measured using the Bomb Risk Elicitation Task - BRET (Crosetto and Filippin, 2013). This task asks participants to choose how many boxes to collect out of 100, knowing that 99 boxes contain £0.10 while one contains a bomb, but without knowing in which box the bomb is located. They can therefore choose their preferred lottery among 100 lotteries whose outcomes and probabilities are fully described only by one parameter, i.e., the number of collected boxes. Earnings increase linearly with the number of boxes collected, but they are all lost if the bomb lies in one of the collected boxes. In the first two chapters, risk behaviour is measured both before and after the treatment manipulation, and feedback on the peers’ ex-ante risk behaviour is used as a channel to study peer influence on the subjects’ ex-post risk behaviour. The first two chapters provide new evidence that individual risk behaviour is influenced by the risk behaviour of the peer group and offer one explanation for why peer effects are not always present and vary in intensity. This is due to the fact that individuals are more influenced by those peers with whom they feel more bonded. Specifically, in the first chapter I study how group identity (that is, the portion of an individual’s self-concept derived from the sense of belonging to the social group) affects peer effects on risk behaviour. I induce different levels of group identity through different matching protocols (random or based on individual painting preferences) and the possibility of interacting with group members via an online chat in a group task. I find that subjects are affected by their peers when taking decisions and that a stronger group identity amplifies the influence of peers: painting preferences matching significantly reduces the heterogeneity of risk behaviour compared with random matching. On the other hand, introducing a group task has no significant effect on behaviour, possibly because this interaction does not always contribute to enhancing group identity. The second chapter digs deeper into this evidence by investigating the role of the incentive structure that characterizes the individuals’ environment. Since the first chapter shows that peer effects vary in intensity, I hypothesize that different types of incentive schemes may have different effects on peer relationships and, therefore, affect peer effects on risk behaviour. Using a real effort task, which consists of recognizing the value and the country of origin of a random sequence of Euro coins, I compare piece-rate compensation first with a cooperation-based and then with a competition-based incentive scheme. I find that competition significantly reduces attachment to peers and more than halves peer influence on risk behaviour compared with piece-rate compensation, despite the fact that the latter effect is not statistically significant. Such findings suggest that, when designing and evaluating an optimal compensation scheme, it may be important to also consider how peer effects on subsequent risk behaviour will in turn affect future decisions involving risk. For example, in research and development, competition may improve the results of current projects, but risk attitudes will shape the types of future projects that are attempted. The third chapter restricts the attention to competition and enquires whether this type of incentive scheme has a direct effect on risk-taking behaviour, beyond any social comparison, and whether its impact on subsequent risk behaviour is heterogeneous according to gender. Risk behaviour is measured after the performance of a real effort task, consisting of recognizing the value and country of origin of Euro coins, incentivized either as a tournament with fixed rewards or as a random draw with the same monetary payoffs. The data show that competition does not significantly affect subsequent risk-taking behaviour when considering the full sample. However, there is a positive relationship between competition and risk aversion for males, who become significantly more risk-averse after losing a competition than after randomly earning the same low payoff. In contrast, males do not become more risk-seeking after winning the tournament, while the average risk-taking behaviour of females is unaffected by tournament participation and outcomes. The reaction of males to negative outcomes might be driven by intrinsic motives, such as emotions or a shift in the locus of control from internal to external. Overall, the evidence presented here shows that risk attitudes are not immutable but may be shaped by external factors. Of particular importance is the role played by the risk behaviour of peers, which begins to emerge even when bonds are weak and becomes stronger as the social link intensifies. Any policy that aims to change risk attitudes (or that does so indirectly) will thus see its effects spread to the target subjects’ peers, and may amplify its success if the peer group is chosen wisely. Changing the characteristics of the subjects’ environment by introducing competition weakens their attachment to the competing peers and may attenuate peer effects on risk behaviour. In addition, competition per se has no impact on subsequent risk behaviour, except for males who become more risk-averse after losing.

This paper is focused on the effect board gender diversity has on firm risk-taking behaviour within the domain of mergers and acquisitions (M&A). As existing literature has produced mixed findings concerning board effectiveness in the corporate context, it is suggested that external contingencies might have an impact on the influence of female board representativeness. In response, this study examines the impact of board gender diversity on the degree of acquisitiveness by taking a crosscultural perspective. Building on social identity theory, this paper predicts that female representativeness at the board level is negatively associated with a firm’s acquisitiveness. Additionally, this study theorizes and empirically tests the moderating effect of culture in terms of gender egalitarianism and uncertainty avoidance. The panel data used in this analysis consists of 111 Global 500 firms from 17 different countries, covering the period 2012 - 2016. Results in this paper support the notion that board gender diversity is negatively associated with acquisitiveness and that culture in terms of gender egalitarianism has a weakening effect on this relationship. Moreover, this paper contributes to existing research by offering new insights onto the role culture plays in the relationship between board gender diversity and firm risk-taking behaviour and, as a result, helps to reconcile mixed findings of previous literature focused on this topic.

Thesis (MA)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The present study stems from a concern with the possible occurrence of alcohol abuse on a university campus. The major focus is an exploration of the drinking habits of mostly undergraduate students. An adequate understanding of the above would simplify the task of the university authorities of formulating a relevant alcohol policy and action plan. The survey involves a self-completion questionnaire. The data analysis concentrated on Pearson's correlations and chisquare tests. Significant relationships between the level of alcohol use on the one hand and gender, residence, language, other substance abuse, sport participation, religion, moral values, and sexual activity on the other hand was found. Finally a profile of high-risk, heavier drinking students are provided. / AFRIKAANSE OPSOMMING: Die huidige studie spruit uit 'n besorgdheid oor die voorkoms van alkohol misbruik op 'n universiteitskampus. Die primêre fokus is 'n verkenning van die drinkgewoontes van hoofsaaklik voorgraadse studente. 'n Omvattende begrip van bogenoemde sal die taak vergemaklik van die universiteitsowerhede om 'n toepaslike alkoholbeleid en -aksieplan te formuleer. Die ondersoekende studie behels 'n selfvoltooings vraelys. Die data-analise fokus op Pearson se korrelasies en chi-kwadraat toetse. Beduidende verbande is gevind tussen vlak van alkohol gebruik aan die een kant en geslag, verblyf, taal, ander substansgebruik, sportdeelname, godsdiens, morele waardes en seksuele aktiwiteit aan die ander kant. Laastens word 'n profiel van die hoë risiko, swaarder drinkende studente verstrek.

Do investment portfolios meet the needs and preferences of investors? Can the portfolio selection process be improved? Traditionally, investor preferences have been identified using risk tolerance questionnaires. These questionnaires have recently attracted a fair deal of criticism. However, there has been little focus as to whether the questionnaires are useful in predicting investors' risk-taking behaviour. In this thesis, an explanatory sequential mixed methods approach was employed to find answers to the primary research question: what factors determine risk-taking behaviour in investment decisions? This thesis looked at the risk-taking behaviour of investors in Canada (N=192) and the risk-taking advice provided by financial advisers in Canada (N=155), collectively risk-taking decisions. The results suggested that return expectations and demographic variables were important predictors of risk-taking decisions, whereas risk tolerance questionnaires were not. Further investigation suggested that investment literacy impacted risk-taking decisions while investment experience impacted both return expectations and risk-taking decisions. In a novel contribution by this thesis, additional perspective was provided by qualitative analysis using semi-structured interviews with investors and advisers. From the results of the qualitative analysis, the author suggests that discovery and self-discovery, a consistent approach and a focus on process versus outcome are key attributes valued by both investors and advisers. The thesis concluded with implications and recommendations for stakeholders, including a greater focus on return expectations, more training in discovery for advisers, simulating investment experience for prospective investors and including investment literacy in school curricula.

O objetivo desta pesquisa foi investigar a relação entre comportamentos sexuais de risco e religiosidade entre jovens brasileiros de nível socioeconômico baixo. A pesquisa foi dividida em dois estudos: transversal (em São Paulo, Porto Alegre, Recife e Campo Grande) e longitudinal (em Porto Alegre). Participaram 4078 jovens com idades entre 14 e 24 anos, 46,5% masculino e 53,5% feminino, vivendo em situação de pobreza. Foi utilizado um instrumento auto-aplicável e confidencial de 109 questões. Os dados foram coletados em escolas e ONGs de forma coletiva. Foram desenvolvidas duas escalas, uma medindo religiosidade e outra comportamento de risco sexual (um indice composto por idade da primeira relação sexual, uso de camisinha, uso de métodos contraceptivos, abuso sexual e gravidez). A média de idade dos jovens participantes foi de 16,14 anos (SD=1,83) e não foi encontrada diferença entre moças e rapazes. Os resultados indicam que 97,2% são heterossexuais e 46,8% já tiveram a primeira relação sexual. A média de idade para o debute sexual foi de 14,24 anos (SD=0,60). A média do escore de comportamento de risco sexual foi de 0,60 (SD 0,60) com diferença significativa entre moças e rapazes (t=8,99; p<0,001), com média mais elevada para as moças (0,68 e 0,51). Em termos de religiosidade, a maioria se auto-declarou como católicos (40,8%), seguidos por aqueles que não têm uma religião (24,5%) e protestantes (20,5%). Houve uma diferença significativa para o nível de religiosidade (t=11,47; p<0,001) entre moças e rapazes, a média do índice de religiosidade para eles foi de -0,21 (SD=1,03) e para elas foi de 0,19 (SD=0,94). A amostra foi dividida em três grupos de religiosidade: alta, média e baixa religiosidade. O grupo com alta religiosidade teve o maior indice de comportamento sexual de risco (F=7,82; p<0,001). De seis indicadores de risco sexual, somente a relação sexual foi associada ao nível de religiosidade (participantes mais religiosos tenderam a atrasar a idade da primeira relação sexual). Dados longitudinais revelaram que a experiência sexual tende a diminuir o nível de religiosidade. Os resultados sugerem que, embora a religiosidade seja um fator de proteção atrasando a primeira relação sexual, esta não se mantem como um fator de proteção significativo após o debute sexual. / The aim of this research was to investigate the relationship between sexual risk taking behavior and religiosity among poor youth in Brazil. The research was divided into two studies: cross-sectional (in the cities of São Paulo, Porto Alegre, Recife and Campo Grande) and longitudinal (in Porto Alegre). The research was conducted with 4078 young people, ages 14-24, 46.5 % males and 53.5% females, living in poor social conditions. Data were collected using a confidential self-administered questionnaire with 109 questions. Data collection was conducted in groups at schools and non-governmental organizations (NGOs). Two scales were developed from the data, the first measuring religiosity and the second measuring sexual risk taking behavior (a composite of age of first sexual intercourse, condom use, contraception method, sexual abuse and pregnancy). The mean age was 16.14 years old (SD 1.83) and there is no age difference between males and females. Results indicate that 97.2% were heterosexual and 46,8% have had their first sexual intercourse. The mean age for the sexual debut was 14.24 years old (SD 1.93). The mean score of sexual risk taking behavior was 0.60 (SD 0.60) for the overall sample. A significant difference was found between males and females (t=8.99; p<0,001), showing that the girls have higher scores than the boys (0.68 and 0.51). Concerning religiosity, the majority was catholic (40.8%), followed by people who do not have a religion (24.5%) and protestants (20.5%). There was a significant gender difference for religiosity (t=11.47; p<0.001), the mean for males was -0.21 (SD 1.03) and for females was 0.19 (SD 0.94). The sample was divided into three groups of religiosity: high, medium or low religiosity. The high religiosity group has the highest level of sexual risk taking behavior (F=7.82; p<0.001). Of the six risk-taking indicators, only sexual debut was associated with religiosity (respondents who were more religious tended to delay sexual intercourse). Longitudinal data showed that experiencing sexual intercourse decrease religiosity levels. The findings suggest that, although religiosity plays a protective role delaying sexual debut, this is not a predictive variable for sexual risk taking behavior among poor young people in Brazil, once they are not abstinent.

O objetivo desta pesquisa foi investigar a relação entre comportamentos sexuais de risco e religiosidade entre jovens brasileiros de nível socioeconômico baixo. A pesquisa foi dividida em dois estudos: transversal (em São Paulo, Porto Alegre, Recife e Campo Grande) e longitudinal (em Porto Alegre). Participaram 4078 jovens com idades entre 14 e 24 anos, 46,5% masculino e 53,5% feminino, vivendo em situação de pobreza. Foi utilizado um instrumento auto-aplicável e confidencial de 109 questões. Os dados foram coletados em escolas e ONGs de forma coletiva. Foram desenvolvidas duas escalas, uma medindo religiosidade e outra comportamento de risco sexual (um indice composto por idade da primeira relação sexual, uso de camisinha, uso de métodos contraceptivos, abuso sexual e gravidez). A média de idade dos jovens participantes foi de 16,14 anos (SD=1,83) e não foi encontrada diferença entre moças e rapazes. Os resultados indicam que 97,2% são heterossexuais e 46,8% já tiveram a primeira relação sexual. A média de idade para o debute sexual foi de 14,24 anos (SD=0,60). A média do escore de comportamento de risco sexual foi de 0,60 (SD 0,60) com diferença significativa entre moças e rapazes (t=8,99; p<0,001), com média mais elevada para as moças (0,68 e 0,51). Em termos de religiosidade, a maioria se auto-declarou como católicos (40,8%), seguidos por aqueles que não têm uma religião (24,5%) e protestantes (20,5%). Houve uma diferença significativa para o nível de religiosidade (t=11,47; p<0,001) entre moças e rapazes, a média do índice de religiosidade para eles foi de -0,21 (SD=1,03) e para elas foi de 0,19 (SD=0,94). A amostra foi dividida em três grupos de religiosidade: alta, média e baixa religiosidade. O grupo com alta religiosidade teve o maior indice de comportamento sexual de risco (F=7,82; p<0,001). De seis indicadores de risco sexual, somente a relação sexual foi associada ao nível de religiosidade (participantes mais religiosos tenderam a atrasar a idade da primeira relação sexual). Dados longitudinais revelaram que a experiência sexual tende a diminuir o nível de religiosidade. Os resultados sugerem que, embora a religiosidade seja um fator de proteção atrasando a primeira relação sexual, esta não se mantem como um fator de proteção significativo após o debute sexual. / The aim of this research was to investigate the relationship between sexual risk taking behavior and religiosity among poor youth in Brazil. The research was divided into two studies: cross-sectional (in the cities of São Paulo, Porto Alegre, Recife and Campo Grande) and longitudinal (in Porto Alegre). The research was conducted with 4078 young people, ages 14-24, 46.5 % males and 53.5% females, living in poor social conditions. Data were collected using a confidential self-administered questionnaire with 109 questions. Data collection was conducted in groups at schools and non-governmental organizations (NGOs). Two scales were developed from the data, the first measuring religiosity and the second measuring sexual risk taking behavior (a composite of age of first sexual intercourse, condom use, contraception method, sexual abuse and pregnancy). The mean age was 16.14 years old (SD 1.83) and there is no age difference between males and females. Results indicate that 97.2% were heterosexual and 46,8% have had their first sexual intercourse. The mean age for the sexual debut was 14.24 years old (SD 1.93). The mean score of sexual risk taking behavior was 0.60 (SD 0.60) for the overall sample. A significant difference was found between males and females (t=8.99; p<0,001), showing that the girls have higher scores than the boys (0.68 and 0.51). Concerning religiosity, the majority was catholic (40.8%), followed by people who do not have a religion (24.5%) and protestants (20.5%). There was a significant gender difference for religiosity (t=11.47; p<0.001), the mean for males was -0.21 (SD 1.03) and for females was 0.19 (SD 0.94). The sample was divided into three groups of religiosity: high, medium or low religiosity. The high religiosity group has the highest level of sexual risk taking behavior (F=7.82; p<0.001). Of the six risk-taking indicators, only sexual debut was associated with religiosity (respondents who were more religious tended to delay sexual intercourse). Longitudinal data showed that experiencing sexual intercourse decrease religiosity levels. The findings suggest that, although religiosity plays a protective role delaying sexual debut, this is not a predictive variable for sexual risk taking behavior among poor young people in Brazil, once they are not abstinent.

O objetivo desta pesquisa foi investigar a relação entre comportamentos sexuais de risco e religiosidade entre jovens brasileiros de nível socioeconômico baixo. A pesquisa foi dividida em dois estudos: transversal (em São Paulo, Porto Alegre, Recife e Campo Grande) e longitudinal (em Porto Alegre). Participaram 4078 jovens com idades entre 14 e 24 anos, 46,5% masculino e 53,5% feminino, vivendo em situação de pobreza. Foi utilizado um instrumento auto-aplicável e confidencial de 109 questões. Os dados foram coletados em escolas e ONGs de forma coletiva. Foram desenvolvidas duas escalas, uma medindo religiosidade e outra comportamento de risco sexual (um indice composto por idade da primeira relação sexual, uso de camisinha, uso de métodos contraceptivos, abuso sexual e gravidez). A média de idade dos jovens participantes foi de 16,14 anos (SD=1,83) e não foi encontrada diferença entre moças e rapazes. Os resultados indicam que 97,2% são heterossexuais e 46,8% já tiveram a primeira relação sexual. A média de idade para o debute sexual foi de 14,24 anos (SD=0,60). A média do escore de comportamento de risco sexual foi de 0,60 (SD 0,60) com diferença significativa entre moças e rapazes (t=8,99; p<0,001), com média mais elevada para as moças (0,68 e 0,51). Em termos de religiosidade, a maioria se auto-declarou como católicos (40,8%), seguidos por aqueles que não têm uma religião (24,5%) e protestantes (20,5%). Houve uma diferença significativa para o nível de religiosidade (t=11,47; p<0,001) entre moças e rapazes, a média do índice de religiosidade para eles foi de -0,21 (SD=1,03) e para elas foi de 0,19 (SD=0,94). A amostra foi dividida em três grupos de religiosidade: alta, média e baixa religiosidade. O grupo com alta religiosidade teve o maior indice de comportamento sexual de risco (F=7,82; p<0,001). De seis indicadores de risco sexual, somente a relação sexual foi associada ao nível de religiosidade (participantes mais religiosos tenderam a atrasar a idade da primeira relação sexual). Dados longitudinais revelaram que a experiência sexual tende a diminuir o nível de religiosidade. Os resultados sugerem que, embora a religiosidade seja um fator de proteção atrasando a primeira relação sexual, esta não se mantem como um fator de proteção significativo após o debute sexual. / The aim of this research was to investigate the relationship between sexual risk taking behavior and religiosity among poor youth in Brazil. The research was divided into two studies: cross-sectional (in the cities of São Paulo, Porto Alegre, Recife and Campo Grande) and longitudinal (in Porto Alegre). The research was conducted with 4078 young people, ages 14-24, 46.5 % males and 53.5% females, living in poor social conditions. Data were collected using a confidential self-administered questionnaire with 109 questions. Data collection was conducted in groups at schools and non-governmental organizations (NGOs). Two scales were developed from the data, the first measuring religiosity and the second measuring sexual risk taking behavior (a composite of age of first sexual intercourse, condom use, contraception method, sexual abuse and pregnancy). The mean age was 16.14 years old (SD 1.83) and there is no age difference between males and females. Results indicate that 97.2% were heterosexual and 46,8% have had their first sexual intercourse. The mean age for the sexual debut was 14.24 years old (SD 1.93). The mean score of sexual risk taking behavior was 0.60 (SD 0.60) for the overall sample. A significant difference was found between males and females (t=8.99; p<0,001), showing that the girls have higher scores than the boys (0.68 and 0.51). Concerning religiosity, the majority was catholic (40.8%), followed by people who do not have a religion (24.5%) and protestants (20.5%). There was a significant gender difference for religiosity (t=11.47; p<0.001), the mean for males was -0.21 (SD 1.03) and for females was 0.19 (SD 0.94). The sample was divided into three groups of religiosity: high, medium or low religiosity. The high religiosity group has the highest level of sexual risk taking behavior (F=7.82; p<0.001). Of the six risk-taking indicators, only sexual debut was associated with religiosity (respondents who were more religious tended to delay sexual intercourse). Longitudinal data showed that experiencing sexual intercourse decrease religiosity levels. The findings suggest that, although religiosity plays a protective role delaying sexual debut, this is not a predictive variable for sexual risk taking behavior among poor young people in Brazil, once they are not abstinent.

La dispersion est un trait d'histoire de vie clé pour les processus écologiques et évolutifs dans les populations naturelles. Les dernières recherches se sont notamment focalisées sur les corrélations entre traits comportementaux et la dispersion, ceci afin de mettre en évidence des syndromes comportementaux de dispersion, tout en démontrant la base génétique de la dispersion. Les dispersants ne seraient donc pas une part aléatoire d'une population, mais des individus montrant des stratégies particulières qui augmenteraient leur chances de succès. Cette thèse s'est orientée vers trois objectifs de recherche majeurs. Le premier est la mise en évidence d'une base génétique de la probabilité de disperser dans une population fragmentée de gobe-mouches à collier Ficedula albicollis. Les résultats nous ont montré, au-delà de l'estimation de la base génétique de la dispersion, une distribution spatiale non aléatoire de l'apparentement dans cette population, qui pourrait être dû à des effets génétiques sur les règles de décision de choix de l'habitat. Le deuxième s'intéresse à la corrélation phénotypique et génétique entre le comportement de dispersion natale et le comportement de défense du nid, chez le martinet alpin Tachymarpis melba. Nous avons montré que la dispersion natale et le comportement de défense du nid sont négativement corrélés au niveau phénotypique mais aussi génétique dans ces populations. Enfin, le troisième nous à conduit à tester l'existence de syndromes comportementaux de dispersion, c'est-à-dire si les dispersants présentent un profil comportemental particulier, leur permettant en particulier de coloniser de nouveaux sites, chez le gobe-mouche à collier / Dispersal is a key like history trait for ecological and evolutionary processes in wild population. The last researching particularly focused on the correlation between behavioural trait and dispersal, in order to emphasize the existence of behavioural syndromes of dispersal, and on the estimation of the genetic basis of the dispersal behaviour. Dispersant individuals could not be a random part of the population, but individuals showing particular strategies, that help them to succeed in their dispersal attempt. This thesis has three main aims of research. The first is to show a genetic basis of the dispersal propensity in a fragmented population of collared flycatchers (Ficedulla albicollis). We shown not only the genetic bases of the dispersal, but also a non-random spatial distribution of relationship between individuals in this population, that might be due to genetic effects on the decision rules of habitat choice in this population. The second aim concerns phenotypic and genetic correlation between the natal dispersal and a behavioural trait, the nest-defense behaviour, in the alpin swift (Tachymarpis melba). We shown that natal dispersal and nest-defense behaviour are negatively correlated at a phenotypic level, but also at a genetic level in theses populations. Finally, the third aim attempt to test the existence of behavioural syndrome of dispersal, that is if dispersant individuals have a particular behavioural profile, which enable them to colonize new sites, in the collared flycatcher

Dispersal is a key life history trait for ecological and evolutionary processes in wild populations. The latest research has particularly focused on the correlation between behavioural traits and dispersal, in order to emphasize the existence of behavioural syndromes of dispersal, and on the estimation of the genetic basis of the dispersal behaviour. Dispersing individuals are not a random part of the population, but are individuals showing particular strategies, that help them to succeed in their dispersal attempt. This thesis has three main aims of research. The first is to show a genetic basis of the dispersal propensity in a fragmented population of collared flycatchers (Ficedulla albicollis). We show, not only, the genetic bases of the dispersal, but also a non-random spatial distribution of relationship between individuals in this population, that might be due to genetic effects on the decision rules of habitat choice in this population. The second aim concerns phenotypic and a genetic correlation between the natal dispersal and a behavioural trait, the nest-defense behaviour, in the alpin swift (Tachymarptis melba). We showed that natal dispersal and nest-defense behaviour were negatively correlated at a phenotypic level, but also at a genetic level in these populations. Finally, the third aim attempts to test the existence of a behavioural syndrome of dispersal, that is if dispersing individuals have a particular behavioural profile, which enable them to colonize new sites, in the collared flycatcher. / <p>The exmination will be videolinked to seminar room 1003 Evolutionary Biology Centre, EBC, Uppsala University.</p>