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Thesis (Ph.D.)--Bowling Green State University, 2007. / Document formatted into pages; contains xiv, 346 p. Includes bibliographical references.

A seleção de grupo foi proposta inicialmente em um contexto ecológico como uma força seletiva agindo sobre o grupo da mesma forma que a seleção individual atua sobre os indivíduos que compõem a população. Apesar da oposição inicial dos biólogos evolucionários tradicionais, nas últimas décadas estes conceitos têm se revelado bastante úteis no estudo de problemas pouco relacionados a sua motivação original. Na primeira parte desta tese, investigamos um modelo de seleção de grupo que usa a extinção diferenciada como força seletiva atuando sobre os grupos. Neste modelo a população é composta de grupos que no jargão de seleção de grupo são denominados demes. As demes por sua vez são habitadas por indivíduos de dois tipos (altruístas não-altruístas) que podem reproduzir-se, sofrer mutação e migrar de uma deme a outra. A dinâmica da população é implementada lançando-se mão de matrizes de transição associadas a cada um destes eventos, levando a um conjunto de equações de recorrência aclopadas cuja iteração dá o estado estacionário da freqüência dos diferentes tipos de demes na população. Examinado inicialmente no regime determinístico, no qual o número de demes é infinito mas o número de indivíduos em cada demes é finito, este modelo revelou o papel desestabilizador das mutações sobre as demes totalmente altruístas. Seguido ao regime determinístico, fizemos um estudo do modelo ainda com extinção diferenciada, considerando o número de demes finito, com vistas a investigar os efeitos provocados pela finitude da população no estado estacionário da freqüência de demes na população. Observamos um aumento ainda maior da instabilidade do estado altruísta provocado pela mutação em face da diminuição da quantidade de demes presentes na população. Finalmente, investigamos um modelo para a evolução da produção de enzimas que usa a seleção de grupo característico em sua concepção. Esta modalidade de seleção de grupo baseia-se no conceito de freqüência média subjetiva, uma freqüência estimada com base na estrutura da população que neste caso também é composta por grupos. Apresentamos uma nova formulação matemática para o mesmo problema com a qual abordamos outro modelo recentemente proposto na literatura que trata da evolução de características altruístas. / Group selection was proposed initially within an ecological context as an evolutionary selective force acting on a group in the same way as the individual selection does on the individuals composing the population. Despite the initial resistance of the conservative evolutionary biologists concerning the ideas of group selection, in the last decades those concepts have been very useful in the investigation of other problems not very correlated to its original motivation. In the first part of this thesis, we investigate a group selection model based on differential extinction as a selective force. In this model, the population is divided into groups, which in the context of group selection are termed demes. The demes are inhabited by two different types of individuals, namely, altruists and non-altruists, which are capable of reproducing themselves, mutating to the other type, or migrating to another deme. The population dynamics is formulated resorting to the transition matrices associated to those events, resulting in a set of coupled recursion equations describing the time evolution of the frequencies of the different types of demes in the population. Considering first the deterministic regime, which corresponds to the limit of infinite demes, each deme containing only a finite number of individuals, this model reveals the destabilizing role of the mutation mechanism on the altruistic demes. Following that analysis, we investigate a stochastic version of the above model, in which the number of demes is finite. The focus was on the effects of the finiteness of the population in the stationary frequencies of the demes. We verified that the instability of the altruistic state due to mutations becomes even more pronounced when the number of demes is reduced. Finally, we investigate a model for the evolution of enzymes production using the concepts of trait-group selection. This kind of group selection is based on the definition of the average subjective frequency, which is estimated by considering the structure of the population. We propose a new mathematical formulation to this problem, which we then use to study a recently proposed model to describe the evolution of altruistic features.

Thesis (M.A.)--Bowling Green State University, 2006. / Document formatted into pages; contains v, 45 p. Includes bibliographical references.

A seleção de grupo foi proposta inicialmente em um contexto ecológico como uma força seletiva agindo sobre o grupo da mesma forma que a seleção individual atua sobre os indivíduos que compõem a população. Apesar da oposição inicial dos biólogos evolucionários tradicionais, nas últimas décadas estes conceitos têm se revelado bastante úteis no estudo de problemas pouco relacionados a sua motivação original. Na primeira parte desta tese, investigamos um modelo de seleção de grupo que usa a extinção diferenciada como força seletiva atuando sobre os grupos. Neste modelo a população é composta de grupos que no jargão de seleção de grupo são denominados demes. As demes por sua vez são habitadas por indivíduos de dois tipos (altruístas não-altruístas) que podem reproduzir-se, sofrer mutação e migrar de uma deme a outra. A dinâmica da população é implementada lançando-se mão de matrizes de transição associadas a cada um destes eventos, levando a um conjunto de equações de recorrência aclopadas cuja iteração dá o estado estacionário da freqüência dos diferentes tipos de demes na população. Examinado inicialmente no regime determinístico, no qual o número de demes é infinito mas o número de indivíduos em cada demes é finito, este modelo revelou o papel desestabilizador das mutações sobre as demes totalmente altruístas. Seguido ao regime determinístico, fizemos um estudo do modelo ainda com extinção diferenciada, considerando o número de demes finito, com vistas a investigar os efeitos provocados pela finitude da população no estado estacionário da freqüência de demes na população. Observamos um aumento ainda maior da instabilidade do estado altruísta provocado pela mutação em face da diminuição da quantidade de demes presentes na população. Finalmente, investigamos um modelo para a evolução da produção de enzimas que usa a seleção de grupo característico em sua concepção. Esta modalidade de seleção de grupo baseia-se no conceito de freqüência média subjetiva, uma freqüência estimada com base na estrutura da população que neste caso também é composta por grupos. Apresentamos uma nova formulação matemática para o mesmo problema com a qual abordamos outro modelo recentemente proposto na literatura que trata da evolução de características altruístas. / Group selection was proposed initially within an ecological context as an evolutionary selective force acting on a group in the same way as the individual selection does on the individuals composing the population. Despite the initial resistance of the conservative evolutionary biologists concerning the ideas of group selection, in the last decades those concepts have been very useful in the investigation of other problems not very correlated to its original motivation. In the first part of this thesis, we investigate a group selection model based on differential extinction as a selective force. In this model, the population is divided into groups, which in the context of group selection are termed demes. The demes are inhabited by two different types of individuals, namely, altruists and non-altruists, which are capable of reproducing themselves, mutating to the other type, or migrating to another deme. The population dynamics is formulated resorting to the transition matrices associated to those events, resulting in a set of coupled recursion equations describing the time evolution of the frequencies of the different types of demes in the population. Considering first the deterministic regime, which corresponds to the limit of infinite demes, each deme containing only a finite number of individuals, this model reveals the destabilizing role of the mutation mechanism on the altruistic demes. Following that analysis, we investigate a stochastic version of the above model, in which the number of demes is finite. The focus was on the effects of the finiteness of the population in the stationary frequencies of the demes. We verified that the instability of the altruistic state due to mutations becomes even more pronounced when the number of demes is reduced. Finally, we investigate a model for the evolution of enzymes production using the concepts of trait-group selection. This kind of group selection is based on the definition of the average subjective frequency, which is estimated by considering the structure of the population. We propose a new mathematical formulation to this problem, which we then use to study a recently proposed model to describe the evolution of altruistic features.

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Group therapy has been demonstrated to be effective through a number of factors. Group theorists and researchers have attempted to identify client characteristics that would enable the clinician to determine a client's appropriateness for group therapy. Reviews of research have identified client expectancies and positive and negative interpersonal skills as promising predictors of group process, outcome, and attrition. The Group Selection Questionnaire (GSQ) was created to provide clinicians with a short and useful tool to aid them in identifying potential members for therapy groups, and has shown positive preliminary results in the past. This study presents tentative support for the factor structure of the GSQ and compares the GSQ and the Group Therapy Questionnaire (GTQ), another well established pre-group selection measure. Convergent validity of the GSQ is generally supported. GSQ Demeanor, Expectancy and Total scale scores correlate significantly with the GTQ Expectations about Group scale. In addition, GSQ Participation, Expectancy and Total scale scores correlate with GTQ Interpersonal Problems, with more interpersonal problems indicating fewer positive interpersonal skills, better expectancies for group, and stronger overall group readiness. Implications of these findings are discussed as well as future research directions.

The aim of this study is to place a wide variety of two-phenotype frequency-dependent selection models into a unified population-genetic framework. This work is used to illuminate the possible genetic constraints that may exist in such models, and to address the question of evolutionary modification of these constraints. The first part of Chapter 1 synthesizes from the literature a general framework for applying a genetic structure to a simple class of two-phenotype models. It shows that genetic constraints may prevent the population from achieving a predicted phenotypic equilibrium, but the population will equilibrate at a point that is as close as possible to the phenotypic equilibrium. The second part of Chapter 1 goes on to ask whether evolutionary modification of the genetic system might be expected to remove these constraints. Chapter 2 provides an example of the application of the framework developed in Chapter 1. It presents re-analysis of a model for the evolution of social behavior by reciprocation (Brown et al. 1982). The genetic results of Chapter 1 apply to this model without modification. I show that Brown et al. were unnecessarily restrictive in their assumptions about the types of genetic systems that support their conclusions. Chapter 3 discusses some models for the evolution of altruism that do not fit the assumptions of Chapter 1, despite their two-phenotype structure. These models violate the fundamental assumption of Chapter 1, this being the way in which individual fitness is derived from the behavioral fitnesses. The first part is a complete, in-depth analysis of diploid sib-sib kin selection. I show that some results from the basic model can be used, provided the behavioral inclusive fitness functions are substituted for the true behavioral fitnesses. The second part is an analysis of the validity of the concept of behavioral structure, as introduced by Michod and Sanderson (1985). I show that this concept is flawed as a general principle. Chapter 4 extends the basic model to the case of sex-allocation evolution. I show how many of the central results of sex-allocation theory can be derived more simply using a two-phenotype framework.

A critical examination of Popper’s falsificationism as a methodological criterion of demarcation led to the development o f a supplementary means of distinguishing science from pseudo- science The discipline is made the unit of appraisal and its pattern o f historical development b used as the indicator of demarcation. Results of a test of this indicator against astrology and physical optics accord with our basic judgm ents of these disciplines. The indicator effectively reveals that scientific creationism is pseudo-science, and that evolutionary biology is genuine science. Three fundam ental approaches to scientific investigation, viz. v erificationism , falsificationism and m ulti-cornered testing (M CT) are contrasted. MCT is distinguished by competition between hypotheses, which makes it more informative than at least the naive versions of the other two approaches. While competition does not produce immediate victors, it does make demands on theories, which can be augmented by prescribing a series of independent tests. The comparative method implies the existence of two types of evidence. Common evidence is that which io predicted or explained by two or more rival hypotheses. Discriminatory evidence favours one rival over the others. It is argued that in both the fields of species biology and speciation there have been instances o f over-relying on common evidence, o f indistinctly defining alternative hypotheses, of ro t following their logical consequences and of not using exisiing discriminatory evidence to adjudicate between these hypotheses. Species concepts and definitions of modes o f speciation are evaluated. Normative principles are suggested for defining species and other important terms in evolutionary biology, and for testing species concepts and modes of speciation. The advantages and limitations o f a historical indicator of demarcation and the merits and principles of the comparative approach to method are discussed and illustrated using the analoev of a mathematical game. Scientific crcanomsni is shown to have a coating of scientific method, but to have systematically violated fundamental methodological principles. D arn in ’* method in contrast, had a comparative structure, and distinguished between common *nd discriminatory evidence. While there are methodological problems sn evolutionary biology, these are shown to be minor in comparison to that four*! in to c n o fk ciratxxiiun.

The aim of the work is the selection of individuals or groups of employees using the methods multicriteria evaluation of alternatives. First outline the issue of human resources and focusing specifically on the acquisition, selection and recruitment of employees. Then we move on the theory of decision making, testing of non-dominated solution and calculation of the Saaty's weights. We will describe in detail the methods: ORESTE, WSA, TOPSIS, ELECTRE I, ELECTRE III and Cook-Seiford method for the selection of the expert team. In other parts of the work of the above findings apply to a particular fictional example, carry out a comparison of the methods for the multicriteria evaluation of the alternatives and choose group of 10 candidates, to which we will use the group expert choice for group selection. At the conclusion we summarize the work and we determine the winning candidate or the winning group.