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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Shadow of the Leviathan : the role of dominance in the evolution of costly punishment

Gordon, David Stuart January 2014 (has links)
Costly ‘altruistic’ punishment, where an individual intervenes to punish someone for behaving unfairly towards another or for violating a social norm, seems to be vital for large-scale cooperation. However, due to the costs involved, the evolution of this behaviour has remained a puzzle. The thesis initially describes why punishment is costly and explains why current theories do not sufficiently explain its evolution in the context of these costs. The thesis then offers a solution to this puzzle in the form of a dominance-based theory of the evolution of punishment. The theoretical underpinnings of this theory are discussed in reference to the previous literature, specifically how a dominant position provides sufficient heterogeneity in the cost and benefits of punishment to allow the behaviour to evolve at the individual-level of selection. Across 10 studies, the thesis empirically investigates the role dominance is theorised to play in costly punishment behaviour. First, the judgements observers make about punishers are investigated. It is demonstrated that punishers are perceived as dominant but, unlike individuals who engage in other aggressive behaviours, punishers are also well liked. While successful punishers are judged to be of the highest rank in a social group, the wider social judgements of punishers are dependent on the attempt at punishment only; successful and unsuccessful punishers are seen as equally dominant and well liked, suggesting that the willingness to attempt punishment can honestly signal both dominance and ones pro-sociality. However, additional studies show that observers a) perceive subordinate punishers will face a great deal of retaliation, b) show surprise when subordinates attempt to punish, and c) expect that dominants will punish and be successful, whereas subordinates are expected to never punish. Thus, while there are reputational benefits from punishment, only dominant individuals can actually access them. Second, the effect of a dominant position on punishment behaviour is investigated. Two studies sought to simulate the greater access to resources that dominants enjoy, and demonstrate that individuals who receive more resources from group-level cooperation will punish free-riding more frequently and more severely than those who receive less resources. Moreover, individuals who are in a stable dominant position, i.e. who can continually benefit to a greater degree than others from group cooperation, punish even more frequently and severely than when individuals receive additional resources alone. The results show that individuals only punish when it is cheap for them to do so and when investment in the public good (by punishing) can produce higher future returns for them. A dominant position provides the opportunity for both of these. Further studies demonstrate that individuals at the centre of a social network, an example of a ‘real life’ informal dominant position, are more sensitive to unfairness when making punishment decisions compared to those at the periphery of a group. However, when punishment decisions are public, and there are no economic incentives to punish, individuals behave in a similar manner regardless of social position. Taken together, the results of the empirical studies support the proposed dominance-theory of costly punishment. The theoretical implications of the dominance-theory of punishment are discussed in reference to both the proximate occurrence of punishment and its evolutionary origins in dominance and dominant behaviours. The practical implications of this theory will also be discussed, specifically in regard to when and why individuals will act in defence of the public good. While further investigation is necessary, a dominance-theory of punishment explains both results of this thesis and the findings of the wider literature, and as such provides a coherent and compelling explanation for the evolution of costly punishment and its associated emotions.
52

Origem e evolução da desigualdade material hereditária: uma abordagem dos Sistemas Adaptativos Complexos / Origins and evolution of hereditary material inequality: a Complex Adaptive Systems approach

Freitas, Mikael Peric de 20 May 2016 (has links)
A desigualdade material hereditária teria surgido no registro arqueológico pela primeira vez por volta de 6.500 A.C. na região da Mesopotâmia, tendo posteriormente emergido de maneira independente em diferentes localidades e contextos, dentro de um intervalo de tempo relativamente curto. Muitas teorias foram propostas para explicar os fenômenos, porém sua compreensão permanece em aberto. Buscou-se, aqui, abordar a questão sob a perspectiva dos Sistemas Adaptativos Complexos, construindo um Modelo Baseado em Agentes que teve como base teórica a literatura que trata da questão, focada nos últimos vinte anos do debate, aprofundada em dois estudos de caso: a Mesopotâmia e a Costa Noroeste da América do Norte. Dos nove parâmetros testados oito apresentaram relação direta com a assimetria material dos indivíduos podendo colaborar com a emergência da desigualdade material hereditária, de forma que fomos levados a considerar a igualdade material e a cooperação presente entre os caçadores e coletores como propriedades decorrentes de uma estrutura social de criticalidade auto-organizada / The hereditary material inequality would have emerged for the first time in the archaeological record around 6.500 BC in Mesopotamia, emerging after it repeatedly and independently in different localities and contexts, in a small time period. Many theories have been proposed but the complete understanding of the issue remains open to debate. Thus, we have proposed here an approach of the phenomenon under the Complex Adaptive Systems perspective, through which an agent-based model have been built. Constitutes the background of the model the working papers and text books written in the last two decades, which were later checked agains two case studies: Mesopotamia and Northwest Coast, in North America. Among the nine parameters tested in the model eight presented direct relation to the material asymmetry of individuals, potentially participating of the precesses involved in the emergence of material inequality. This results leads us to consider the possibility of the egalitarian and cooperative social structures of huntergatherers to be one of self-organized criticality
53

Experimental archaeology and hominid evolution: establishing a methodology for determining handedness in lithic materials as a proxy for cognitive evolution

Unknown Date (has links)
Human handedness is likely related to brain lateralization and major cognitive innovations in human evolution. Identifying handedness in the archaeological record is, therefore, an important step in understanding our cognitive evolution. This thesis reports on experiments in identifying knapper handedness in lithic debitage. I conducted a blind study on flakes (n=631) from Acheulean handaxes replicated by right- and left-handed flintknappers. Several flake characteristics significantly indicated handedness, with a binary logistic regression correctly predicting handedness for 71.7% of the flakes. However, other characteristics were not associated with handedness. This is a result of personal knapping styles, as additional analyses show that individual knappers associate with some attributes better than handedness does. Continued work on these methodologies will enable analysis of Paleolithic assemblages in the future, with the ultimate goal of tracking population-level hominid handedness rates through time and using them as a proxy for cognitive evolution and language acquisition. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
54

Direito, casamento e amor: o casamento, um caminho para encontrar o absoluto / Law, marriage and lovethe: marriage, one way to find the absolute

Korte, Paulo Thomas 29 April 2016 (has links)
Submitted by Jailda Nascimento (jmnascimento@pucsp.br) on 2016-09-22T18:54:32Z No. of bitstreams: 1 Paulo Thomas Korte.pdf: 1265772 bytes, checksum: a8e8621b611435008baa221a90f4d522 (MD5) / Made available in DSpace on 2016-09-22T18:54:32Z (GMT). No. of bitstreams: 1 Paulo Thomas Korte.pdf: 1265772 bytes, checksum: a8e8621b611435008baa221a90f4d522 (MD5) Previous issue date: 2016-04-29 / This study demonstrates the inquietude of the human with himself in trying to educe his anxiety. His anxiety comes from the comprehension where he comes rom, what he is and where he goes. The human, composed by a material part (body) and another immaterial part (soul), tries to reach a place where there is not any feeling of missing but where is plenitude and satisfaction. Many philosophies and religions show that this place exists and it is possible to reach it. There are many ways to reach it. More than that, the present study questions if there is some need to follow someone to reach the Absolute or if it is possible to reach it by yourself without any kind of imitation. Übermensch or “Superman”, Absolute, 7th grade of soul, Self, excellence, are these all names for the same hing? Animus, Anima, the male and female archetypes, the shadow as the levels o the Jungian way to find, through the marriage, the Absolute / O presente trabalho buscou apresentar a inquietação do ser humano consigo mesmo, na tentativa de reduzir sua angústia em compreender de onde vem, o que significa, e para onde vai. O ser humano composto de uma parte material (corpo) e outra parte imaterial (alma) procura chegar a um lugar onde não maishá sensação de falta, no qual existe plenitude e satisfação. Muitas filosofias e religiões indicam que há este lugar, e que é possível nele chegar. Muitos caminhos existem para se chegar lá. Além disso, no presente trabalho, questiona-se se há necessidade de seguir alguém para chegar a este Absoluto ou se é possível chegar só e sem qualquer tipo de imitação. Super-homem, Absoluto, 7ºgrau da alma, Self, excelência moral são nomes diferentes para dizer mesma coisa? Animus e Anima, os arquétipos masculinos e femininos, e a sombra como estágios do caminho junguiano para encontrar o Absoluto
55

Origem e evolução da desigualdade material hereditária: uma abordagem dos Sistemas Adaptativos Complexos / Origins and evolution of hereditary material inequality: a Complex Adaptive Systems approach

Mikael Peric de Freitas 20 May 2016 (has links)
A desigualdade material hereditária teria surgido no registro arqueológico pela primeira vez por volta de 6.500 A.C. na região da Mesopotâmia, tendo posteriormente emergido de maneira independente em diferentes localidades e contextos, dentro de um intervalo de tempo relativamente curto. Muitas teorias foram propostas para explicar os fenômenos, porém sua compreensão permanece em aberto. Buscou-se, aqui, abordar a questão sob a perspectiva dos Sistemas Adaptativos Complexos, construindo um Modelo Baseado em Agentes que teve como base teórica a literatura que trata da questão, focada nos últimos vinte anos do debate, aprofundada em dois estudos de caso: a Mesopotâmia e a Costa Noroeste da América do Norte. Dos nove parâmetros testados oito apresentaram relação direta com a assimetria material dos indivíduos podendo colaborar com a emergência da desigualdade material hereditária, de forma que fomos levados a considerar a igualdade material e a cooperação presente entre os caçadores e coletores como propriedades decorrentes de uma estrutura social de criticalidade auto-organizada / The hereditary material inequality would have emerged for the first time in the archaeological record around 6.500 BC in Mesopotamia, emerging after it repeatedly and independently in different localities and contexts, in a small time period. Many theories have been proposed but the complete understanding of the issue remains open to debate. Thus, we have proposed here an approach of the phenomenon under the Complex Adaptive Systems perspective, through which an agent-based model have been built. Constitutes the background of the model the working papers and text books written in the last two decades, which were later checked agains two case studies: Mesopotamia and Northwest Coast, in North America. Among the nine parameters tested in the model eight presented direct relation to the material asymmetry of individuals, potentially participating of the precesses involved in the emergence of material inequality. This results leads us to consider the possibility of the egalitarian and cooperative social structures of huntergatherers to be one of self-organized criticality
56

Abiotic and Biotic Drivers of Turnover and Community Assembly in African Mammals

January 2018 (has links)
abstract: Climate and environmental forcing are widely accepted to be important drivers of evolutionary and ecological change in mammal communities over geologic time scales. This paradigm has been particularly influential in studies of the eastern African late Cenozoic fossil record, in which aridification, increasing seasonality, and C4 grassland expansion are seen as having shaped the major patterns of human and faunal evolution. Despite the ubiquity of studies linking climate and environmental forcing to evolutionary and ecological shifts in the mammalian fossil record, many central components of this paradigm remain untested or poorly developed. To fill this gap, this dissertation employs biogeographical and macroecological analyses of present-day African mammal communities as a lens for understanding how abiotic change may have shaped community turnover and structure in the eastern African Plio-Pleistocene. Three dissertation papers address: 1) the role of ecological niche breadth in shaping divergent patterns of macroevolutionary turnover across clades; 2) the effect of climatic and environmental gradients on community assembly; 3) the relative influence of paleo- versus present-day climates in structuring contemporary patterns of community diversity. Results of these papers call into question many tenets of current theory, particularly: 1) that niche breadth differences (and, by extension, their influence on allopatric speciation) are important drivers of macroevolution, 2) that climate is more important than biotic interactions in community assembly, and 3) that communities today are in equilibrium with present-day climates. These findings highlight the need to critically reevaluate the role and scale-dependence of climate in mammal evolution and community ecology and to carefully consider potential time lags and disequilibrium dynamics in the fossil record. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2018
57

Quantitative trait variation and adaptation in contemporary humans

Mostafavi, Hakhamanesh January 2019 (has links)
Human genomic data sets are now reaching sample sizes on the order of hundreds of thousands and soon exceeding millions, providing unprecedented opportunities to understand human evolution. Most studies of human adaptation so far have focused on selection that has acted over the past million to few thousand years. However, powered by large data sets, it is now feasible to study allele frequency changes that occur within the short timescale of a few generations, directly observing selection acting in contemporary humans. I take this approach in the work presented in Chapter 1 of this thesis, where we performed a genome-wide scan to identify a set of genetic variants that influence age-specific mortality in present-day samples. Our findings include two variants in the APOE and CHRNA3 loci, as well as sets of variants contributing to a number of traits, including coronary artery disease and cholesterol levels, and intriguingly, to timing of puberty and child birth. New research directions have also opened up with the advent of large-scale genome-wide association studies (GWAS), which have begun to uncover genetic variants underlying a number of human traits, ranging from disease susceptibility to social and behavioral traits such as educational attainment and neuroticism. One such direction is the use of polygenic scores (PGS), which aggregate GWAS findings into one score as a measure of genetic propensity for traits, for phenotypic prediction. A major obstacle to this application is that the prediction accuracy of PGS drops in samples that have a different genetic ancestry than the GWAS sample. Our work, presented in Chapter 2, demonstrates that PGS prediction accuracy is also variable within genetic ancestries depending on factors such as age, sex, and socioeconomic status, as well as GWAS study design. These findings have important implications for the increasing use of these measures in diverse disciplines such as social sciences and human genetics.
58

Peter Wilhelm Lund: o auge das suas investigações científicas e a razão para o término das pesquisas

De Luna Filho, Pedro Ernesto 28 August 2007 (has links) (PDF)
O naturalista dinamarquês Peter Wilhelm Lund (1801-1880), considerado o pai da Paleontologia brasileira, professava a chamada Teoria do Catastrofismo, de Georges Cuvier. Foi para tentar comprovar esta teoria que o naturalista escavou milhares de fósseis nas cavernas de Lagoa Santa (MG) entre 1835 e 1844, quando descreveu dezenas de espécies extintas do período Pleistoceno. Durante este trabalho, Lund descobriu os esqueletos fossilizados de cerca de 30 seres humanos, que ficaram conhecidos como os Homens de Lagoa Santa. Logo após esta descoberta, o naturalista enviou suas coleções para a Dinamarca e pôs um fim nos trabalhos de campo, sem no entanto voltar ao seu país e permanecendo no Brasil até sua morte. <br />A maior questão não respondida sobre a vida de Peter Lund, e o objetivo deste trabalho, é entender porque afinal ele parou de pesquisar? O próprio Lund alegou falta de dinheiro. Mas seus biógrafos escolheram como bode espiatório o cansaço físico e intelectual após anos de trabalho ininterrupto nas cavernas. <br />A resposta, no entanto, encontra-se na coleção de cartas de Lund, arquivadas na Biblioteca Real de Copenhagen. O presente trabalho é resultado do estudo de uma pequena parte desta correspondências. Analisou-se a vida do naturalista à luz da sua relação com a família, mestres e amigos no Brasil e na Dinamarca, na esperança de identificar a razão para o término das pesquisas de um dos mais influentes cientistas do Brasil no século XIX.
59

Mitochondria and Human Evolution

Ingman, Max January 2003 (has links)
<p>Mitochondrial DNA (mtDNA) has been a potent tool in studies of the evolution of modern humans, human migrations and the dynamics of human populations over time. The popularity of this cytoplasmic genome has largely been due to its clonal inheritance (in Man) allowing the tracing of a direct genetic line. In addition, a comparatively high rate of nucleotide substitution facilitates phylogenetic resolution among relatively closely related individuals of the same species.</p><p>In this thesis, a statistically supported phylogeny based on complete mitochondrial genome sequences is presented which, for the first time, unambiguously places the root of modern human mitochondrial lineages in Africa in the last 200 thousand years. This conclusion provides strong support for the “recent African origin” hypothesis. Also, the complete genome data underline the problematic nature of traditional approaches to analyses of mitochondrial phylogenies.</p><p>The dispersal of anatomically modern humans from the African continent is examined through single nucleotide polymorphism (SNP) and sequence data. These data imply an expansion from Africa about 57 thousand years ago and a subsequent population dispersal into Asia. The dispersal coincides with a major population division that may be the result of multiple migratory routes to East Asia.</p><p>Also investigated is the question of a common origin for the indigenous peoples of Australia and New Guinea. Previous studies have been equivocal on this question with some presenting evidence for a common genetic origin and other proposing separate histories. Our data reveals an ancient genetic link between Australian Aborigines and the peoples of the New Guinea highlands.</p>
60

Mitochondria and Human Evolution

Ingman, Max January 2003 (has links)
Mitochondrial DNA (mtDNA) has been a potent tool in studies of the evolution of modern humans, human migrations and the dynamics of human populations over time. The popularity of this cytoplasmic genome has largely been due to its clonal inheritance (in Man) allowing the tracing of a direct genetic line. In addition, a comparatively high rate of nucleotide substitution facilitates phylogenetic resolution among relatively closely related individuals of the same species. In this thesis, a statistically supported phylogeny based on complete mitochondrial genome sequences is presented which, for the first time, unambiguously places the root of modern human mitochondrial lineages in Africa in the last 200 thousand years. This conclusion provides strong support for the “recent African origin” hypothesis. Also, the complete genome data underline the problematic nature of traditional approaches to analyses of mitochondrial phylogenies. The dispersal of anatomically modern humans from the African continent is examined through single nucleotide polymorphism (SNP) and sequence data. These data imply an expansion from Africa about 57 thousand years ago and a subsequent population dispersal into Asia. The dispersal coincides with a major population division that may be the result of multiple migratory routes to East Asia. Also investigated is the question of a common origin for the indigenous peoples of Australia and New Guinea. Previous studies have been equivocal on this question with some presenting evidence for a common genetic origin and other proposing separate histories. Our data reveals an ancient genetic link between Australian Aborigines and the peoples of the New Guinea highlands.

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