821 resultados para Ethics, Evolutionary.


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In What We Owe to Each Other, T.M. Scanlon formulated a new version of the ethical theory called contractualism. This theory took reasons considerations that count in favour of judgment-sensitive attitudes to be the fundamental normative notion. It then used normative reasons to first account for evaluative properties. For an object to be valuable, on this view, is for it to have properties that provide reasons to have favourable attitudes towards the bearer of value. Scanlon also used reasons to account for moral wrongness. His contractualism claims that an act is morally wrong if it is forbidden by any set of moral principles that no one could reasonably reject. My thesis consists of five previously published articles which attempt to clarify Scanlon s theory and to defend it against its critics. The first article defends the idea that normative reason-relations are fundamental against Joshua Gert. Gert argues that rationality is a more basic notion than reasons and that reasons can be analysed in terms of their rationally requiring and justifying dimensions. The second article explores the relationship between value and reasons. It defends Scanlon s view according to which reasons are the more basic than value against those who think that reasons are based on the evaluative realm. The last three articles defend Scanlon s views about moral wrongness. The first one of them discusses a classic objection to contractualist theories. This objection is that principles which no one could reasonably reject are redundant in accounting for wrongness. This is because we need a prior notion of wrongness to select those principles and because such principles are not required to make actions wrong or to provide reasons against wrong actions. The fourth article explores the distinctive reasons which contractualists claim there are for avoiding the wrong actions. The last article argues against the critics of contractualism who claim that contractualism has implausible normative consequences for situations related to the treatment of different-sized groups of people.

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The study addresses the question concerning the relationship between ethics and aesthetics in the philosophy of Iris Murdoch. The main argument is that Murdoch s philosophy cannot be accurately understood without an understanding of the relationship she sees between the aesthetic experience and morality. Reading Murdoch s philosophy with this relationship in mind shows that it must be considered as a relevant alternative to the main forms of aesthetic-ethical theories. The study consists of seven previously published articles and a summary. It shows that Murdoch belongs to a tradition of philosophers who seek to broaden the scope of ethics by reference to aesthetic value and aesthetic experience. She sees an attitude responsible for aesthetic experiences as relevant for morality. However, she does not collapse morality into aesthetic experience. The two meet on the level of the subject s attitude towards its object, but there is a distinction between the experiences that accompany the attitudes. Aesthetic experiences can function as a clue to morals in that they present in a pleasing manner moral truths which otherwise might be psychologically too difficult to face. Murdoch equates the aesthetic attitude with virtuous love characterized by unselfish attention to its object. The primary object of such love is in Murdoch s account another human individual in her particularity. She compares the recognition of the other person as a particular existence to the experience of the Kantian sublime and offers her own version of the true sublime which is the experience of awe in the face of the infinity of the task of understanding others. One of the most central claims in Murdoch s philosophy is that human consciousness is evaluatively structured. This claim challenges the distinction between facts and values which has had an immense influence on modern moral philosophy. One argument with which Murdoch supports her claim is the nature of great literature. According to her, the standard of greatness in literature is the authors awareness of the independent existence of individuals in the particularity of their evaluative consciousnesses. The analysis of the standard of greatness in literature is also Murdoch s only argument for the claim that the primary object of the loving unselfish attention is the other particular individual. She is convinced that great literature reveals a deep truth about the human condition with its capacity to capture the particular. Abstract philo¬sophical discourse cannot compete with this capacity but it should take truths revealed by literature seriously in its theorising. Recognising this as Murdoch s stand on the question of the relation between philosophy and literature as forms of human discourse settles whether she is part of what has been called philosophy s turn to literature. The answer is yes.

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This thesis focuses on a connection between temporality and ethics in the philosophy of Emmanuel Levinas. I argue that Levinas understanding of temporality is rooted in the function of pra-impression which in its turn does not belong to the intentional consciousness but reveals a subject as being open to the Other. In the face-to-face situation with the Other the pra-impression is an essential and constitutive force: it fractures the moment of the present, questions subjectivity and generates a new meaning of temporality. As a result a responsible subject is revealed; responsibility for the Other marks a latent birth of the subject which is prior to any origin of subjectivity, it discloses a meaning of time that does not belong to the subject but is found in the Other. In this study I suggest that pra-impression finds its productive force in language, the function of the feminine, and what Levinas calls the other in the same .

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Many species inhabit fragmented landscapes, resulting either from anthropogenic or from natural processes. The ecological and evolutionary dynamics of spatially structured populations are affected by a complex interplay between endogenous and exogenous factors. The metapopulation approach, simplifying the landscape to a discrete set of patches of breeding habitat surrounded by unsuitable matrix, has become a widely applied paradigm for the study of species inhabiting highly fragmented landscapes. In this thesis, I focus on the construction of biologically realistic models and their parameterization with empirical data, with the general objective of understanding how the interactions between individuals and their spatially structured environment affect ecological and evolutionary processes in fragmented landscapes. I study two hierarchically structured model systems, which are the Glanville fritillary butterfly in the Åland Islands, and a system of two interacting aphid species in the Tvärminne archipelago, both being located in South-Western Finland. The interesting and challenging feature of both study systems is that the population dynamics occur over multiple spatial scales that are linked by various processes. My main emphasis is in the development of mathematical and statistical methodologies. For the Glanville fritillary case study, I first build a Bayesian framework for the estimation of death rates and capture probabilities from mark-recapture data, with the novelty of accounting for variation among individuals in capture probabilities and survival. I then characterize the dispersal phase of the butterflies by deriving a mathematical approximation of a diffusion-based movement model applied to a network of patches. I use the movement model as a building block to construct an individual-based evolutionary model for the Glanville fritillary butterfly metapopulation. I parameterize the evolutionary model using a pattern-oriented approach, and use it to study how the landscape structure affects the evolution of dispersal. For the aphid case study, I develop a Bayesian model of hierarchical multi-scale metapopulation dynamics, where the observed extinction and colonization rates are decomposed into intrinsic rates operating specifically at each spatial scale. In summary, I show how analytical approaches, hierarchical Bayesian methods and individual-based simulations can be used individually or in combination to tackle complex problems from many different viewpoints. In particular, hierarchical Bayesian methods provide a useful tool for decomposing ecological complexity into more tractable components.

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Evolutionary history of biological entities is recorded within their nucleic acid sequences and can (sometimes) be deciphered by thorough genomic analysis. In this study we sought to gain insights into the diversity and evolution of bacterial and archaeal viruses. Our primary interest was pointed towards those virus groups/families for which comprehensive genomic analysis was not previously possible due to the lack of sufficient amount of genomic data. During the course of this work twenty-five putative proviruses integrated into various prokaryotic genomes were identified, enabling us to undertake a comparative genomics approach. This analysis allowed us to test the previously formulated evolutionary hypotheses and also provided valuable information on the molecular mechanisms behind the genome evolution of the studied virus groups.

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Environmental variation is a fact of life for all the species on earth: for any population of any particular species, the local environmental conditions are liable to vary in both time and space. In today's world, anthropogenic activity is causing habitat loss and fragmentation for many species, which may profoundly alter the characteristics of environmental variation in remaining habitat. Previous research indicates that, as habitat is lost, the spatial configuration of remaining habitat will increasingly affect the dynamics by which populations are governed. Through the use of mathematical models, this thesis asks how environmental variation interacts with species properties to influence population dynamics, local adaptation, and dispersal evolution. More specifically, we couple continuous-time continuous-space stochastic population dynamic models to landscape models. We manipulate environmental variation via parameters such as mean patch size, patch density, and patch longevity. Among other findings, we show that a mixture of high and low quality habitat is commonly better for a population than uniformly mediocre habitat. This conclusion is justified by purely ecological arguments, yet the positive effects of landscape heterogeneity may be enhanced further by local adaptation, and by the evolution of short-ranged dispersal. The predicted evolutionary responses to environmental variation are complex, however, since they involve numerous conflicting factors. We discuss why the species that have high levels of local adaptation within their ranges may not be the same species that benefit from local adaptation during range expansion. We show how habitat loss can lead to either increased or decreased selection for dispersal depending on the type of habitat and the manner in which it is lost. To study the models, we develop a recent analytical method, Perturbation expansion, to enable the incorporation of environmental variation. Within this context, we use two methods to address evolutionary dynamics: Adaptive dynamics, which assumes mutations occur infrequently so that the ecological and evolutionary timescales can be separated, and via Genotype distributions, which assume mutations are more frequent. The two approaches generally lead to similar predictions yet, exceptionally, we show how the evolutionary response of dispersal behaviour to habitat turnover may qualitatively depend on the mutation rate.

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The noted 19th century biologist, Ernst Haeckel, put forward the idea that the growth (ontogenesis) of an organism recapitulated the history of its evolutionary development. While this idea is defunct within biology, the idea has been promoted in areas such as education (the idea of an education being the repetition of the civilizations before). In the research presented in this paper, recapitulation is used as a metaphor within computer-aided design as a way of grouping together different generations of spatial layouts. In most CAD programs, a spatial layout is represented as a series of objects (lines, or boundary representations) that stand in as walls. The relationships between spaces are not usually explicitly stated. A representation using Lindenmayer Systems (originally designed for the purpose of modelling plant morphology) is put forward as a way of representing the morphology of a spatial layout. The aim of this research is not just to describe an individual layout, but to find representations that link together lineages of development. This representation can be used in generative design as a way of creating more meaningful layouts which have particular characteristics. The use of genetic operators (mutation and crossover) is also considered, making this representation suitable for use with genetic algorithms.

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Despite the rhetoric of schools serving the needs of specific communities, it is evident that the work of teachers and principals is shaped by government imperatives to demonstrate success according to a set of standard ‘benchmarks’. In this chapter, we draw from our current study of new forms of educational leadership emerging in South Australian public primary schools to explore the ways in which test-based accountability requirements are being mediated by principals in schools that serve high poverty communities. Taking an institutional ethnography approach we focus on the everyday work of a principal and a literacy leader in one suburban primary school to show the complexity of the impact of national testing on practices of literacy leadership. We elaborate on the inescapable textual framings and tasks faced by the principal and literacy leader, and those that they create and modify – such as a common literacy agreement and ‘literacy chats’ between a literacy leader and classroom teacher – in order to ‘hold on to ethics’. We argue that while leaders’ and teachers’ everyday work is regulated by ‘ruling relations’ (Smith, 1999), it is also organic and responsive to the local context. We conclude with a reflection on the important situated work that school leaders do in mediating trans-local policies that might otherwise close down possibilities for engaging ethically with students and their learning in a particular school.

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Productivity is predicted to drive the ecological and evolutionary dynamics of predator-prey interaction through changes in resource allocation between different traits. However, resources are seldom constantly available and thus temporal variation in productivity could have considerable effect on the species' potential to evolve. To study this, three long-term microbial laboratory experiments were established where Serratia marcescens prey bacteria was exposed to predation of protist Tetrahymena thermophila in different prey resource environments. The consequences of prey resource availability for the ecological properties of the predator-prey system, such as trophic dynamics, stability, and virulence, were determined. The evolutionary changes in species traits and prey genetic diversity were measured. The prey defence evolved stronger in high productivity environment. Increased allocation to defence incurred cost in terms of reduced prey resource use ability, which probably constrained prey evolution by increasing the effect of resource competition. However, the magnitude of this trade-off diminished when measured in high resource concentrations. Predation selected for white, non-pigmented, highly defensive prey clones that produced predation resistant biofilm. The biofilm defence was also potentially accompanied with cytotoxicity for predators and could have been traded off with high motility. Evidence for the evolution of predators was also found in one experiment suggesting that co-evolutionary dynamics could affect the evolution and ecology of predator-prey interaction. Temporal variation in resource availability increased variation in predator densities leading to temporally fluctuating selection for prey defences and resource use ability. Temporal variation in resource availability was also able to constrain prey evolution when the allocation to defence incurred high cost. However, when the magnitude of prey trade-off was small and the resource turnover was periodically high, temporal variation facilitated the formation of predator resistant biofilm. The evolution of prey defence constrained the transfer of energy from basal to higher trophic levels, decreasing the strength of top-down regulation on prey community. Predation and temporal variation in productivity decreased the stability of populations and prey traits in general. However, predation-induced destabilization was less pronounced in the high productivity environment where the evolution of prey defence was stronger. In addition, evolution of prey defence weakened the environmental variation induced destabilization of predator population dynamics. Moreover, protozoan predation decreased the S. marcescens virulence in the insect host moth (Parasemia plantaginis) suggesting that species interactions outside the context of host-pathogen relationship could be important indirect drivers for the evolution of pathogenesis. This thesis demonstrates that rapid evolution can affect various ecological properties of predator-prey interaction. The effect of evolution on the ecological dynamics depended on the productivity of the environment, being most evident in the constant environments with high productivity.

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Predicting evolutionary outcomes and reconstructing past evolutionary transitions are among the main goals of evolutionary biology. Ultimately, understanding the mechanisms of evolutionary change will also provide answers to the timely question of whether and how organisms will adapt to changing environmental conditions. In this thesis, I have investigated the relative roles of natural selection, random genetic drift and genetic correlations in the evolution of complex traits at different levels of organisation from populations to individuals. I have shown that natural selection has been the driving force behind body shape divergence of marine and freshwater threespine stickleback (Gasterosteus aculeatus) populations, while genetic drift may have played a significant role in the more fine scale divergence among isolated freshwater populations. These results are concurrent with the patterns that have emerged in the published studies comparing the relative importance of natural selection and genetic drift as explanations for population divergence in different traits and taxa. I have also shown that body shape and armour divergence among threespine stickleback populations is likely to be biased by the patterns of genetic variation and covariation. Body shape and armour variation along the most likely direction of evolution the direction of maximum genetic variance reflects the general patterns of variation observed wild populations across the distribution range of the threespine stickleback. Conversely, it appears that genetic correlations between the sexes have not imposed significant constraints on the evolution of sexual dimorphism in threespine stickleback body shape and armour. I have demonstrated that the patterns of evolution seen in the wild can be experimentally recreated to tease out the effects of different selection agents in detail. In addition, I have shown how important it is to take into account the correlative nature of traits, when making interpretations about the effects of natural selection on individual traits. Overall, this thesis provides a demonstration of how considering the relative roles of different mechanism of evolutionary change at different levels of organisation can aid in an emergence of a comprehensive picture of how adaptive divergence in wild populations occurs.

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The International Conference on End of Life: Law, Ethics, Policy and Practice was held at Queensland University of Technology, Brisbane, Australia in August 2014. It was co-hosted by the Australian Centre for Health Law Research, the Dalhousie Health Law Institute (Canada) and the Tsinghua Health Law Research Center (China). The conference attracted almost 350 delegates from 26 countries and included representation from over a dozen different disciplines with an interest in end of life care.

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Evolutionary genetics incorporates traditional population genetics and studies of the origins of genetic variation by mutation and recombination, and the molecular evolution of genomes. Among the primary forces that have potential to affect the genetic variation within and among populations, including those that may lead to adaptation and speciation, are genetic drift, gene flow, mutations and natural selection. The main challenges in knowing the genetic basis of evolutionary changes is to distinguish the adaptive selection forces that cause existent DNA sequence variants and also to identify the nucleotide differences responsible for the observed phenotypic variation. To understand the effects of various forces, interpretation of gene sequence variation has been the principal basis of many evolutionary genetic studies. The main aim of this thesis was to assess different forms of teleost gene sequence polymorphisms in evolutionary genetic studies of Atlantic salmon (Salmo salar) and other species. Firstly, the level of Darwinian adaptive evolution affected coding regions of the growth hormone (GH) gene during the teleost evolution was investigated based on the sequence data existing in public databases. Secondly, a target gene approach was used to identify within population variation in the growth hormone 1 (GH1) gene in salmon. Then, a new strategy for single nucleotide polymorphisms (SNPs) discovery in salmonid fishes was introduced, and, finally, the usefulness of a limited number of SNP markers as molecular tools in several applications of population genetics in Atlantic salmon was assessed. This thesis showed that the gene sequences in databases can be utilized to perform comparative studies of molecular evolution, and some putative evidence of the existence of Darwinian selection during the teleost GH evolution was presented. In addition, existent sequence data was exploited to investigate GH1 gene variation within Atlantic salmon populations throughout its range. Purifying selection is suggested to be the predominant evolutionary force controlling the genetic variation of this gene in salmon, and some support for gene flow between continents was also observed. The novel approach to SNP discovery in species with duplicated genome fragments introduced here proved to be an effective method, and this may have several applications in evolutionary genetics with different species - e.g. when developing gene-targeted markers to investigate quantitative genetic variation. The thesis also demonstrated that only a few SNPs performed highly similar signals in some of the population genetic analyses when compared with the microsatellite markers. This may have useful applications when estimating genetic diversity in genes having a potential role in ecological and conservation issues, or when using hard biological samples in genetic studies as SNPs can be applied with relatively highly degraded DNA.