Thesis (PhD)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: How organisms respond to unpredictable environments is a fundamental question in evolutionary ecology. For example, plants may reduce the risk of reproductive failure by spreading their reproductive effort in space (dispersal) or in time (dormancy, iteroparity). Similarly, different plant breeding systems, (for example the ability to autonomously self-fertilise) may reduce the risk of reproductive failure in environments where pollination in particular is unreliable. Each of these strategies may be affected by selective pressures exerted by heterogeneous abiotic and biotic environments (e.g. unreliable rainfall patterns or range edge habitats). However, there is little theoretical or empirical consensus on how these strategies are related. In Chapter 2, I explore the association between dispersal and breeding system traits and range edge proximity. I show that annual daisies from Namaqualand, South Africa, are characterised by two discreet syndromes: high selfing ability associated with good dispersal and obligate outcrossing associated with lower dispersal, regardless of range position. This chapter illustrates that selection on both breeding system and dispersal traits may act consistently across distribution ranges. Because co-flowering plants often share pollinators, their fecundity is likely affected by changes in pollinator visitation rates or the transfer of conspecific relative to heterospecific pollen. In Chapter 3 I experimentally investigate the effects of con- and heterospecific density and spatial distribution pattern on pollination and fecundity in annual Namaqualand daisies. I show that increasing conspecific density and aggregation enhanced fecundity through increased mate availability and reduced heterospecific interference, independent of pollinator visitation rates. Moreover, I demonstrate the benefits of autonomous selfing when mates are limited and the potential for interspecific pollen transfer is high. In Chapter 4, I examine relative investment in dispersal vs. dormancy in seed heteromorphic Dimorphotheca (Asteraceae) species in relation to life history, rainfall unpredictability and range edge proximity. I show annuals and perennials differ significantly in the relative investment in different dispersal strategies. However, my findings provide little support for theoretical predictions of bet-hedging strategies in unpredictable or range edge habitats. This chapter emphasises the role of local environmental factors on fruit set that may obscure expected patterns across broad climatic gradients. Because of different costs and benefits of dispersal in space and time, we may expect negative patterns of covariation among dispersal and dormancy as alternative risk-reducing strategies. In Chapter 5, I provide evidence for a trade-off between these traits across 27 wind- dispersed daisy species from South Africa. This trade-off did not depend on life history effects, but was inconsistent at different levels of biological organisation. I also show that the effects of life history on spatial and temporal dispersal were inconsistent. Taken together, my research illustrates the importance of simultaneously investigating different risk-reducing strategies, because associations among them are clearly complex and often contradict theoretical expectations. Moreover I show that the effects of life history and phylogenetic relatedness cannot be disregarded. My findings underscore the importance of dispersal in space and time as well as autonomous selfing as risk-reducing responses to unreliable environments.

This study utilizes stable isotope and dental microwear analyses to elucidate diet and subsistence practices of indigenous Muchik peoples interred at two sites in the Lambayeque region of northern Peru: La Capilla Santa María Magdalena De Eten (CSMME) (n=17) and La Capilla Del Niño Serranito (CNS) (n=18). Burials at CNS date to the Early Colonial Period (A.D. 1533-1620), while burials at CSMME date to the Mid- to Late-Colonial Period (A.D. 1625-1760). Dental microwear and stable isotope investigations reveal a highly correlated dietary profile across both sites, which suggests consistent subsistence practices across the Colonial Period, insofar as can be measured using these techniques. However, there is significant differences between CNS and CSMME in dental microwear features indicating the foods consumed by all members at each site—since sex and age are not significantly different between the two sites—is perhaps attributable to the influence of Spanish colonial rule to the degree to which these dental microwear features capture larger patterns in these two populations. Although samples sizes are limited, at CNS, the frequency of fine scratches and small pits increase with age and coarse scratches decrease between childhood and adolescence, indicative of transitions in diet or the use of the teeth during the maturation. Further, statistical inquiry found no significant dental microwear differences between site, age, or sex in the studied populations.

The purpose of this research was to determine how predator control influences nest survival and changes in life history strategies of birds. All studies were conducted at two sites: one site had very little mammal control, while the other site is a 'mainland island' in which all introduced mammals were trapped or poisoned. Nest survival rates of introduced and native species were compared between the two sites by locating and monitoring nests of nine species. I found that mammalian predator control increased nest survival rates of both introduced and native species, but the incrase of nest survival was more pronounced in native species. The influence of predator control on the plasticity of life history strategies in introduced and native New Zealand birds was also examined. Some life history strategies (e.g. time spent incubating, frequency of visits to the nest) changed significantly in the area with predator control, while other life history traits (e.g. clutch size) did not vary between areas. I found that both introduced and native New Zealand birds changed a variety of life history traits and that the changes were likely a plastic response to the recent change in predator numbers. As it has been suggested that birds may become less responsive to mammals when predators are controlled, I tested the response of birds to a model of a feral cat. Birds in the predator control area were significantly less likely to recognise the cat model as a potential threat. This suggests the recognition of predators can be rapidly lost from a population. My research confirms that mammal control can increase nest success of native species, but reductions in predator numbers can also change a variety of life history traits and behaviours. As the removal of mammalian predators also appears to make birds less responsive to potential predators, it is important for continued mammalian control once management has begun. Otherwise, any reintroduction of predatory mammals into controlled sites would likely place such bird populations at greater risk as they would have behaviours suited to an environment with lowered nest predation risk.

Ecological communities along gradients of environmental stress are thought to be structured by trade-offs between resisting biotic interactions in physically benign habitats and successfully exploiting physically stressful habitats. However, these trade-offs are likely to be affected by the predictability of abiotic stressors, and variation in the strength of biotic interactions. I investigated community assembly and food web interactions in ponds across an unpredictable gradient of water inundation (pond permanence) in Canterbury, New Zealand. Pond community composition and species richness were strongly influenced by pond permanence. However, species in temporary ponds were a nested subset of generalists that were also found in permanent ponds, rather than a unique assemblage of temporary pond specialists. Subsequent experiments indicated predator impact decreased with pond permanence, partially due to the foraging suppression of predatory invertebrates in permanent ponds by fish. Weak predation in permanent ponds combined with unpredictable drying regimes likely selected for generalist traits, and resulted in community assembly being driven by a gradient of drying stress rather than trade-offs between biotic interactions and drying. Furthermore, predator impact increased over time in temporary ponds. In predictable snow-melt ponds in the Colorado Rocky Mountains, seasonal windows of weak predation were exploited by vulnerable species, leading to increased diversity within habitats. However in unpredictable systems like Canterbury, temporal increases in predation risk that depend on drying history are likely to increase variability in the spatial arrangement of suitable habitats for particular species. This should further favour the evolution of generalist traits and reduce the importance of trade-offs between predation and drying in the assembly of communities. Considering the predictability of disturbance regimes and the spatial and temporal variation in biotic interactions will greatly enhance understanding and management of communities in heterogeneous landscapes.

Polygyny is the most common mating system in mammalian species (95%), yet our understanding of polygynous systems and microevolutionary processes is still limited. Pinniped mating systems range from extreme polygyny (e.g. elephant seals) to sequential female defence by males and hence have often been used as models for mating system studies. Parentage analysis has enabled the examination of mating success, the identification of pedigrees, and the elucidation of social organisation, greatly enhancing our understanding of mating systems (Chapter 1). However, such analyses are not without pitfalls, with erroneous assignments common in open systems (i.e. when parental and offspring samplings are incomplete). We investigated the effects of the user-defined parameters on the accuracy of parental assignment using two commonly used parental allocation programme, CERVUS and PASOS (Chapter 2). We showed that inaccurate user-defined parameters in CERVUS and PASOS can lead to highly biased output e.g. the assignment rate at 95% CL of offspring with a sampled known mother to sampled males decreased from 58% to 32% when the proportion of candidate males sampled in the parameter options decreasing 4-fold. We found that the use of both CERVUS and PASOS for parentage assignment can increase the likelihood of correctly allocating offspring to sampled parents to 97% in our study system. Incorrect parental assignment can bias estimates of various biological parameters, such as lifetime reproductive success and mate choice preference, and hence bias ecological and evolutionary interpretations. Here, we propose solutions to increase the power of parentage assignment and hence decrease the bias in biological parameter estimates. In addition, we analysed the effects of the intrinsic bias in likelihood assignment approaches towards assigning higher probability of parentage on individuals with rare alleles and those with heightened offspring-parent matches, which increase with the number of homozygous loci (Chapter 3). We showed that, as a consequence of the algorithms employed in the programmes CERVUS and PASOS, heterozygote males with rare genotypes are assigned higher rates of parentage than males with common alleles. Consequently, where two males could both be biological fathers of a given offspring, parentage assignment will more often go to the male with the rarer alleles (most often in heterozygous loci). Thus, the commonly used parentage assignment methods may systematically bias the results of parentage analyses towards supporting the notion that females prefer more genetically unusual, most often heterozygous, males. Such a bias may sway investigators towards incorrectly supporting the concept that females choose genetically more unusual males for heterozygosity fitness benefits that underpin the good genes hypothesis, when in fact no such relationship may exist. In polygynous mammals, successful males mate with multiple females by competing with and limiting the access of other males to females. When the status of many males (age, size, health, genetic etc.) prevents them from achieving the primary mating tactic, theory predicts selection for a diversification of male mating tactics. Recent studies in pinnipeds have shown that observed male mating success was correlated to male paternity success in some species (elephant-seals), but not in others (grey seals). The existence of alternative mating strategies can explain those discrepancies. Chapter 4 implemented the guidelines provided in Chapter 2 and 3 and focused on the polygynous New Zealand fur seal Arctocephalus forsteri, predicting that 1) competition for females is likely to cause a diversification of male mating tactics; and 2) that alternative tactics can yield reproductive success. Our results indicated three male behavioural profiles; one corresponded to large territorial males and two illustrated a continuum of alternative tactics employed by non-territorial subordinate males. Our study highlights that holding a territory is not a necessary condition for reproductive success in a population of otariids. The degree of sexual size dimorphism in polygynous species is expected to increase with the degree of intra-sexual competition and in turn with the degree of polygyny. The life history of an individual is the pattern of resource allocations to growth, maintenance, and reproduction throughout its lifetime. Both females and males incur viability costs of mating and reproduction. However, male viability costs due to increase growth and male-male competition can be greater than female viability costs of mate choice and reproduction. Although an abundant literature on sexual dimorphism in morphology, physiology, and parasite infections is available, little is known on the intra-sexual differences in physiology and parasite infections associated to the reproductive success of different mating strategies in mammalian species. Chapter 5 examined the reproductive costs between territorial and subordinate males New Zealand fur seal related to their relative reproductive success using a multidisciplinary approach (behaviour, genetics, endocrinology, parasitology). We found that dominant New Zealand fur seal males endure higher reproductive costs due to the direct and indirect effects of high testosterone levels and parasite burdens. Our study highlights that holding a territory confers a higher reproductive success, but induces higher costs of reproduction that may impair survival. Understanding microevolutionary processes associated to polygynous systems is fundamental in light of the ongoing anthropogenic alteration of the environment through climatic variations and habitat reduction which ultimately affect opportunity for sexual selection and shape the life history trade-offs.

Behavior-analytic accounts of rule-adherence behavior suggest that rule-governance is a general class of functional (i.e., instrumental) behavior maintained by social consequences (Baum, 2005; Malott & Suarez, 2004; Jacobs et al., in prep.). Evolutionary Life-History (LH) theory suggests that LH strategy may underlie variation in rule-adherence behavior. Based on an integration of these two theories, a theoretical structural model of rule-governance was developed and tested. The structure of this model was used to develop follow-up experiments to test particularly salient links in the model. Consistent with theory, the structural model indicated that slow LH strategy directly and indirectly (through increased moral emotions and increased executive functioning) contributed to strength of rule-governance. Two experiments failed to replicate previously demonstrated effects of executive function depletion or moral identity priming (on moral behavioral outcome measures). Further, self-report measures of slow LH strategy, executive functioning, and rule-governance did not predict prosocial (donating) or rule-defiance (cheating) behavior in laboratory tasks. The limitations of relying solely on either self-report or behavioral tasks of unknown external validity are discussed.

The United States has one of the highest teen pregnancy rates among developed countries and ranks third overall in rates of teen pregnancy out of thirty countries in the Organization for Economic Cooperative Development, OECD (UNICEF, 2007). However, as a country we are spending an enormous amount of money on teen pregnancy prevention programs. For example, the Office of Adolescent Health has implemented grant funding opportunities for teen pregnancy prevention programs and provides approximately $105 million to states to design these programs. These programs include personal responsibility education and abstinence only education (http://www.hhs.gov/ash/oah/oah-initiatives/tpp). If we are spending this much on these programs, why do we still have one of the highest teen pregnancy rates among developed countries? Based on what we have learned from current prevention efforts, the goal of this dissertation is two-fold, to introduce alternative theoretical approaches for prevention design and test determinants and protective factors of sexual risk-taking in adolescence. To obtain these goals, this dissertation was written using the three paper option that contains a theoretical paper and two empirical papers that test hypotheses of determinants of sexual risk-taking in adolescence and possible factors that protect youth from engaging in sexual risk-taking, such as school-wide communication and sexual education. The theoretical paper introduces alternative theoretical approaches to not only target individual behavior that may be risky, but also target the contextual constraints in which teens are operating. The empirical papers analyze possible determinants and protective factors for sexual risk-taking in youth.

This study concerns a rural development project in a village in Bangladesh, initiated in 1973 and followed up regularly until 1991. The original project included the development of a jute handicraft cooperative for women, started and supervised by the author The aims of the thesis are: to describe and analyze the process of change in the lives of some women, engaged in the cooperative, to shed light on this process from the women's perspective, and to discuss what can and should be a target for development education for rural women, coming from the lowest social stratum of society. The ten women who first joined the cooperative are focused in this thesis. The thesis includes their own tales of their experience of the training involved in participation in the cooperative, and their own development process. In the study, the concept of dialogue is used both as a pedagogical method of imparting knowledge, as a form of conversation/interview, aiming at obtaining information from an insider perspective, and also as a concept when compiling data in life histories. The life history approach has been helpful in investigating the educational and developmental process from the women's point of view. Beside skills training, the content of the education for the cooperative was alphabetization, cooperative training and management. Other topics such as nutrition, hygiene, health- and child-care and family planning, were eventually included after the need for training in such areas was articulated in the dialogue between the participating women and the project leader. In contrast to many development projects managed entirely from the top down, all aspects of the training programme were discussed with and approved by the targeted group. The main effect of the training programme was empowerment of the women, which was expressed as an articulated consciousness of their human dignity and a feeling of freedom. The women had developed a professional identity and an awareness of the relevance of contextualised education. A further effect of their new identity was a reduced birth rate. The results of the project are discussed in relation to development education. / digitalisering@umu

This study investigates physical education (PE) teachers careers and professional development in the context of Taiwanese junior high schools (pupils aged 12-14), where a national educational reform the Grade 1-9 Curriculum was launched in 2001. In particular, from teachers perspectives, this study addresses questions about (1) how and why selected Taiwanese PE teachers engage in professional learning over their careers; (2) the impact of the introduction of a new curriculum and policies; (3) ways in which professional learning could be supported more effectively. Eight case study PE teachers, who simultaneously worked as local coordinators, were invited as participants. Life history method was followed by data analysis using constructivist grounded theory to generate findings at three levels: individual life histories, cross-case themes and a theoretical framework. In addition, the process of data analysis, both manually and using a popular software package, is critically compared. The findings suggest that teachers beliefs about professional development were closely connected to their individual career histories, and these were influenced by a set of personal and contextual factors in relation to their professional lives. Moreover, despite a major government curriculum reform, the implementation of the new curriculum resulted in very little change to these teachers practices, because: (1) the curriculum guidelines were very flexible and were difficult for teachers to fully understand; and (2) there was a lack of evaluation of, or accountability for, teachers practices. This study suggests that the Taiwanese government s aspirations for radical changes to teachers practice (both teaching and learning) are more likely to be realised by ensuring that policies and the new curriculum are based on a more realistic understanding of teachers lives and careers.

It is widely documented that non-human organisms express individual differences in behavioural patterns. For example individuals can be categorised as bold or shy and when these individual behavioural differences are consistent through time, they are termed behavioural types (BTs). In recent years research has identified that BTs often correlate across contexts/situations and these correlations are referred to as behavioural syndromes. Behavioural types and syndromes (i.e. personality) have also been implicated as major factors shaping population dynamics and the ability to buffer environmental disturbance. Recent theoretical predictions have proposed that BT variation may be underpinned by life-history strategies; however, these predictions have been little studied to date. Moreover, little research has focused upon environmental influences and the ontogeny of personality. In this thesis I use the Mangrove killifish (Kryptolebias marmoratus), a naturally occurring clonal vertebrate, as a model organism. This species presents a powerful tool providing the ability to replicate within and between isogenic genotypes in a controlled manner. Moreover the natural clonality expressed by this species permits environmental effects upon BT plasticity and BT-life-history interactions to be investigated within a developmental framework. In chapter 2, I present microsatellite genotyping results which show that the founding individuals used to propagate a laboratory population at The University of Exeter represent 20 genetically distinct homozygous genotypes. I additionally address five research questions exploring genotypic, environmental, and developmental effects upon three commonly studied BTs (exploration, boldness and aggression): Firstly; I ask do adult hermaphrodite and secondary males exhibit personality i.e. repeatable BT expression? In chapter 3, I present results showing that both of the sexes express short term personality. Moreover, I show that that genotype is an important factor influencing BTs expressed, regardless of sex, indicating underlying genetic control. Secondly I ask; does genotype level life-history variation underpin personality trait variation during ontogeny? In chapter 4, I show considerable developmental plasticity in behavioural expression between genotypes but not life-history and I find limited behaviour-life-history relationships during development. Thirdly I ask; does the rearing environment influence life-history and behavioural plasticity? In chapter 5, I show that in comparison to a control treatment, the presence of conspecifics during ontogeny results in an average reduction in behavioural scores; however, life-history was unaffected. In addition, I show that development in a low food environment lowered average exploration and growth rate but had no effect on boldness or aggression. Furthermore, fish exposed to a predation risk simulation during ontogeny exhibited similar behavioural scores as the control, yet this treatment generated BTs i.e. personality. My fourth question asks; does the parental rearing environment (utilised in chapter 5) influence behavioural expression in the next generation? In chapter 6, I show that transgeneratonal effects of each parental rearing environment influenced life-history but had a minimal effect upon behaviour in the next generation. Finally I ask; does kin or familiarity influence plasticity in associations and aggression? In chapter 7, I show that genotypes have the ability to discriminate kin and familiars and modulate aggression and association accordingly. These results support the concept that developmental and environmental induced plasticity may be more important than life-history in shaping behaviour. Furthermore, although adults exhibit personality and genotypic effects appear important, genotype interacts with environmental/experiential influences to differentially shape behavioural plasticity during ontogeny. I suggest that theoretical predictions regarding life-history may be insufficient to explain the complexity of animal personality in this species. I discuss these results within developmental and epigenetic frameworks with reference to the ecological significance of these patterns within this species and the animal kingdom as a whole.