The immune system provides protection against parasites and is crucial for survival, but mounting, maintaining and controlling an immune response is expensive. Under limited resources these costs can lead to investment trade-offs between life history traits in order to maximize an individual's fitness. Understanding how these trade-offs relate to immunity can be important in understanding individual variation in fitness and the broader ecological implications that this may have in a population. In the wild there is evidence of trade-offs between life history traits and immunity, but there are relatively few studies which have measured specific aspects of the immune system under natural parasitic exposure. Using reagents developed in domestic sheep, I measured an unusually broad range of immune markers in a wild population of Soay sheep on the island of Hirta, St Kilda, Scotland. These include: T cell subsets (CD4+, CD8+, CD4+ & CD8+ naïve, gamma delta and Foxp3), anti-T.circumcincta (T. circ) antibody isotopes, (IgA, IgE, IgG), leukocyte subtypes (neutrophil:lymphocyte ratio & eosinophils), and leukocyte telomere length (LTL). I found that, in a year under high selection pressure for survival, anti-T. circ IgG positively predicted survival across all ages and for both sexes. Additionally, females had higher proportions of naïve T cells than males; a previously unreported sex difference in a wild mammal. In chapter 2, analysis of lambs in early life found higher growth rates associated with low antibody measures, while lower growth rates related to low antibody measures and high levels of inflammatory marker. I also found that male lambs with high anti-T. circ IgE and IgG were less likely to survive over-winter, contrary to the findings across all ages in chapter 1. In chapter 3, I detected an increase in LTL attrition with age in males >3 years, but this was not significant in females or in younger animals. In male lambs, high investment in horn growth was related to reduced LTL. Changes in LTL were independent of variation in leukocyte cell populations. The data in this thesis demonstrate the complexity of immune variation in the wild, and highlight the value of multiple ecologically relevant markers to understanding the evolutionary implications of resource trade-offs.

In this thesis, I combined field, greenhouse and common-garden experiments to examine the ecological and evolutionary consequences of plant-herbivore interactions and the genetic architecture of fitness-related traits in the insect-pollinated, self-incompatible, perennial herb Arabidopsis lyrata. More specifically, I examined (1) whether damage to leaves and inflorescences affects plant fitness non-additively, (2) whether trichome production is associated with a cost in terms of reduced tolerance to leaf and inflorescence damage, (3) whether young plant resistance to a specialist insect herbivore varies among populations, and (4) whether the evolution of flowering time, floral display and rosette size is constrained by lack of genetic variation or by genetic correlations among traits. A two-year field experiment in a Swedish population showed that damage to rosette leaves and to inflorescences can affect both current and future plant performance of A. lyrata, and that effects on some fitness components are non-additive. A two-year field experiment in another Swedish population indicated that trichome-producing plants are not less tolerant than glabrous plants to leaf and inflorescence damage. In a greenhouse experiment, acceptability of young plants (5-6 weeks old) to ovipositing females and damage received by Plutella xylostella larvae varied considerably among twelve A. lyrata populations. Both oviposition and leaf damage were positively correlated with rosette size, but trichome density in the trichome-producing morph was apparently too low at this developmental stage to influence resistance to P. xylostella. In a common-garden experiment, flowering time, floral display and rosette size varied among four Scandinavian A. lyrata populations, and displayed significant additive genetic variation in some populations. Yet, strong genetic correlations between flowering start and number of flowers, and between petal length and petal width suggest that these traits may not evolve independently. Taken together, the results indicate the need to consider possible long-term and non-additive effects of herbivore damage to different plant parts, that there is no trade-off between trichome production and tolerance to herbivory, that the importance of morphological defenses against herbivory may change through plant ontogeny, and that considerable genetic variation for traits such as flowering time and floral display can be maintained in natural plant populations.

With the increased use of Electronic Control Units (ECUs) in the automotive industry, the system creation and integration becomes progressively more complex. In order to manage this issue, the AUTomotive Open System Architecture (AUTOSAR) was initiated by several of the larger automotive companies and suppliers. Their goal was to create an architecture which will increase the reusability of software, integration of solutions from multiple suppliers and improve scalability. This thesis is made in collaboration with the company CrossControl and covers questions which are specific to their interests, features the AUTOSAR standard has to offer, evaluation of the use of development tools from different vendors, how migration is supported and how the standard affects the required hardware. Among our conclusions is that the AUTOSAR goals of decoupling software application components from the hardware is met to a high degree. Secondly even though file formats are standardized it is not a seamless integration between development tools. Finally, the choice of hardware is not only affected by properties of the standard, but the current versions of tools also limit the choices.

This thesis investigates the impact of avian malaria (Haemosporidia) parasites on the outcome of interspecific competition between two closely related bird species, pied (Ficedula hypoleuca) and collared (F. albicollis) flycatchers. I further investigated how variation in timing of breeding, life history strategies and immune competence genes (MHC genes) modulate the fitness effects of malaria parasites in one of the two species i.e. collared flycatchers. Collared flycatchers colonized the Baltic island Öland in the late 1950-ties and has since then been expanding their breeding range while competitively excluding pied flycatchers from the favourable habitats (deciduous forests). I investigated the underlying mechanisms behind this exclusion by combining detailed long-term breeding data with modern molecular genetic techniques identifying both the presence/absence and lineage specificity of haemosporidian blood parasites. I found that the rapid decline of pied flycatchers can be explained by the combined effects of competition over nestling sites, hybridization and haemosporidian infections. Haemosporidian infections have a negative impact on survival of pied flycatcher females but no detectable effect on collared flycatchers’ longevity or reproductive success. This may be due to the fact that collared flycatchers carry (and are potentially exposed to) a higher diversity of parasites than pied flycatchers, which in turn may select for a higher diversity of MHC genes and hence a better overall protection from the negative impact of parasites. Indeed, functional MHC diversity correlates negatively with malaria prevalence among collared flycatchers from Gotland. Moreover, I found that both, malaria infection intensity and immunoglobulin level influences how infected collared flycatchers respond to increased nestling food-demands. The latter results mean that there is variation in allocation strategies (i.e. in resource allocation between reproductive effort and immune competence) within the collared flycatcher population. Hence, this population has the ability to respond to novel selection pressures in terms of optimal allocation of resources into immune functions. In summary, my results show that local parasites may facilitate the expansion of a new colonizer. This is important in the context of global climate change that will probably increase the colonization rate of southern species and lead to novel host-parasite interactions.

Electricity generation is a vital element of economic growth, and it is necessary to encourage a growth model that does not endanger the capacity of a country to generate electricity. Generating electricity entails costs. This cost is not only economical but can also be, for example, environmental. This implies that there are different trade-offs associated with choices about how to generate electricity, such as technologies, fuels, impact on the environment, construction costs, budget constraints and so on. The Federal Government owns Mexico’s electricity sector. As such not only does it write the rules of the electricity sector but it also executes these rules. The government has stated a series of guiding principles regulating the electricity sector. These guiding principles reflect the priorities that should be taken into account when designing electricity portfolios. My thesis uses financial tools to offer a new approach to the problem of developing electricity portfolios. I assume that the electricity generation mix can be seen as a portfolio of assets. Using portfolio management techniques, I demonstrate scenarios for efficient portfolios given key assumptions about generation choices and prevailing costs. I also illustrate the implications of prioritizing one guiding principle over the other in terms of portfolio cost. Finally, my use of a portfolio modeling approach highlights the complexities inherent in public policy making given the technical and cost-driven nature of the electric power businesses and value chains. My work provides a possible method for more productive evaluation of various approaches in light of mixed priorities and the broad diversity of stakeholders in Mexico. / text

Social insect colonies are complex systems with emergent properties that arise from the cooperation and interaction amongst individuals within colonies. By dividing reproduction and physical labor amongst them, individuals contribute to the growth and ecological success of their colonies, a success that is greater than individuals could achieve on their own. A key characteristic of social insects is a division of labor amongst workers that is determined primarily either by age, morphology, or dominance. Social insects are considered one of the most ecologically successful groups of organisms on earth. Colony life cycles include: 1) growth, in which workers are produced, 2) reproduction, in which queens and males with reproductive capabilities are produced, and 3) senescence. In life history theory, phenotypic plasticity (i.e. a change in phenotype in response to an environmental change), allows organisms to adjust and optimize fitness in response the change in environments. Central to life history theory is the idea that traits have costs and benefits. Using an energetics framework that considers the costs and benefits of traits contributes to our understanding as to why organisms exhibit the sets of traits that they have within their ecological environments. Using the annual bumble bee Bombus impatiens, my dissertation investigates the effects of resource availability on worker production and on the relative allocation of energy towards growth and reproduction within colonies. Bumble bees have a morphological division of labor and concomitantly, they show large intra-colony size variation amongst workers. Because body size is an important life history trait, I also examined the costs and benefits of producing various sized workers. Lastly, I examined the association among worker body size, metabolic rate (a measure of maintenance costs), and lifespan.

Field-programmable gate arrays (FPGAs) have enjoyed increasing use due to their low non-recurring engineering (NRE) costs and their straightforward implementation process. However, it is recognized that they have higher per unit costs, poorer performance and increased power consumption compared to custom alternatives, such as application specific integrated circuits (ASICs). This thesis investigates the extent of this gap and it examines the trade-offs that can be made to narrow it. The gap between 90 nm FPGAs and ASICs was measured for many benchmark circuits. For circuits that only make use of general-purpose combinational logic and flipflops, the FPGA-based implementation requires 35 times more area on average than an equivalent ASIC. Modern FPGAs also contain "hard" specific-purpose circuits such as multipliers and memories and these blocks are found to narrow the average gap to 18 for our benchmarks or, potentially, as low as 4.7 when the hard blocks are heavily used. The FPGA was found to be on average between 3.4 and 4.6 times slower than an ASIC and this gap was not influenced significantly by hard memories and multipliers. The dynamic power consumption is approximately 14 times greater on average on the FPGA than on the ASIC but hard blocks showed promise for reducing this gap. This is one of the most comprehensive analyses of the gap performed to date. The thesis then focuses on exploring the area and delay trade-offs possible through architecture, circuit structure and transistor sizing. These trade-offs can be used to selectively narrow the FPGA to ASIC gap but past explorations have been limited in their scope as transistor sizing was typically performed manually. To address this issue, an automated transistor sizing tool for FPGAs was developed. For a range of FPGA architectures, this tool can produce designs optimized for various design objectives and the quality of these designs is comparable to past manual designs. With this tool, the trade-off possibilities of varying both architecture and transistor-sizing were explored and it was found that there is a wide range of useful trade-offs between area and delay. This range of 2.1 X in delay and 2.0 X in area is larger than was observed in past pure architecture studies. It was found that lookup table (LUT) size was the most useful architectural parameter for enabling these trade-offs.

The schedule of growth, reproduction and survivorship of an individual are the key components of life history, which reflect fitness performance of a genotype. Examining the variation in life history performance among genotypes provides an avenue for which genotypic fitness differences can be compared. The parthenogenetic freshwater zooplankton, Daphnia pulicaria, is a model organism to investigate and disentangle the genotypic from the phenotypic influences of life history variation. While Daphnia spp. life history has been extensively studied, few have examined the effect of low food concentrations on life history traits. Since Daphnia spp. are frequently subjected to periods food limitation caused by natural phytoplankton cycles, it is necessary to understand how individuals respond in low food environments in order to obtain an accurate representation of life history responses among genotypes. In this study, I conducted a set of highly controlled laboratory experiments using multiple genotypes of Daphnia pulicaria under a range of food-limited conditions in order to gain insight into the environmental and genotypic responses of life history traits. I measured a suite of life history traits, growth, reproduction and survivorship, as discrete elements for each individual and synthesized these traits into a representation of the life history schedule. This provided an accurate method to compare genotypes and allowed for identification of trade-offs between life history traits. My results indicate a significant effect of low food concentration on life history traits, causing a decrease in performance of all traits. Additionally, genotypic differences occurred in most traits, however these differences only manifested within the intermediate food levels. There were no genotypic differences in daily reproductive rate, indicating that genotypes only differ in the number of individuals reproducing within an environment. Allocation-based trade-offs among these life history traits were examined within a genotype, however the only trade-off identified was between reproduction and survivorship and this only manifested at low food levels. Even though these genotypes do not co-exist in the same lakes, similar patterns occurred in trade-offs among genotypes. This potentially indicates that trade-offs among genotypes occur due to the same physiological mechanisms witnessed at the individual level. / Thesis (Master, Biology) -- Queen's University, 2011-08-14 11:32:27.808

Antipredator defenses are ubiquitous in aquatic ecosystems. In the widely studied Chaoborus-Daphnia predator-prey system, Daphnia elicit a variety of phenotypically plastic responses to Chaoborus including: morphological, life history, and behavioral responses. While these inducible defenses benefit the prey, metal contaminants have been shown to interfere with chemosensory functions, thereby inhibiting antipredator defenses and decreasing survivorship. However, in lakes with a history of metal contamination, such as Kelly Lake in Sudbury, Ontario, there is evidence to suggest that Daphnia may have adapted to high, ambient copper concentrations. Using seven distinct Daphnia clones that were hatched from resting eggs from Kelly Lake, we examined morphological and life history traits when clones were exposed to either a nominal concentration of copper, kairomone, or a combination of both. As expected, clones displayed a variety of inducible responses in both kairomone-control and kairomone-copper treatments, which was attributed to genetic variability. Expected trade-offs in life history traits were not always observed, suggesting that inducible traits may be coupled. Furthermore, in contradiction to life history theory, one clone exhibited both increased somatic growth and increased reproductive output, indicating that clones likely adopted adaptive strategies to stressors rather than elicitng trade-offs in traditional traits. Our results indicate that environmentally relevant copper concentrations do not inhibit the induction of antipredator defenses in Daphnia from Kelly Lake, and we conclude that Kelly Lake Daphnia have developed an adaptive tolerance to copper. Adaptation to copper contamination may have implications for resilience in natural Kelly Lake populations. / Thesis (Master, Biology) -- Queen's University, 2012-04-03 19:33:59.137

Few empirical studies examine the influence that the maternal parasite environment can have on offspring fitness (maternal effects) in invertebrates. Several recent studies have found that mothers can adjust offspring phenotype to counter the negative effects of parasite infection. In this thesis I subjected the parental generation of the host species, Tenebrio molitor (Insecta: Coleoptera), to a high parasite, high density, or control treatment. Offspring were subsequently subjected to either the same stress, the alternate stress, or to the control, and fitness-related life history traits were measured in both generations. The results from this thesis do not support the hypothesis that T. molitor mothers influence offspring fitness in a positive way. Instead, maternal effects led to a reduction in offspring fitness under both types of stress. At least under some environmental conditions, females invest in their fitness at the expense of their offspring.