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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.
1

Evolution of the hominoid forelimb skeleton from Miocene to present

Selby, Michael 16 April 2012 (has links)
No description available.
2

Perspectivas sobre o reconhecimento de padrões de modularidade e suas implicações para a evolução de morfologias complexas / On the recognition of modularity patterns and its implications for the evolution of morphological systems

Garcia, Guilherme 07 April 2016 (has links)
A modularidade é uma propriedade característica que sistemas biológicos exibem em relação à distribuição de interações entre seus elementos constituintes; neste contexto, um módulo é um subconjunto de elementos que interagem entre si mais do que com outros subconjuntos. Em relação aos sistemas morfológicos, tais propriedades referem-se geralmente à estrutura do componente linear do mapa genótipo/fenótipo; no entanto, as interações genéticas, ontogenéticas e funcionais que produzem fenótipos são descritas de forma adequada através de dinâmicas não-lineares, e uma apreciação completa da complexidade destas interações é necessária para a compreensão das propriedades variacionais do fenótipo. Ademais, dados avanços metodológicos na área da morfometria, é possível escolher diferentes maneiras de representar a variação morfológica, e as diferenças entre as representações podem impactar inferências feitas sobre estas propriedades variacionais. A presente tese tem como objetivo explorar a relação entre representações morfométricas e a caracterização das propriedades variacionais, focada na análise comparativa de tais propriedades em uma escala macroevolutiva; Primatas Antropóides são utilizados como modelo, dada a disponibilidade de uma grande base de dados de mensurações cranianas destes organismo. Esta relação foi avaliada sob três perspectivas diferentes. Em primeiro lugar, estima-se taxas de erro associadas aos testes de hipótese que descrevem padrões de modularidade, relacionadas com três representações morfométricas distintas; tal avaliação é também associada à exploração de um subconjunto da base de dados utilizada aqui, levando-se em consideração a dinâmica de interações ontogenéticas que produzem o crânio dos Antropóides. Os resultados deste capítulo implicam que uma dessas representações, resíduos de Procrustes, não são capazes de detectar padrões de modularidade neste contexto, considerando suas propriedades matemáticas específicas. Outras duas representações, distâncias entre marcos anatômicos e variáveis locais de forma, produzem resultados semelhantes, que estão diretamente associados à dinâmica de desenvolvimento, e as diferenças que elas apresentam são consistentes com suas diferenças principais; taxas de erro para os testes sobre as duas representações também são aceitáveis. O próximo capítulo trata da comparação entre estas duas representações no que diz respeito a estas diferentes propriedades, focado em estimar relações alométricas associadas às variáveis locais de forma e a relação entre estas estimativas e os padrões de modularidade estimados para distâncias entre marcos anatômicos. Os resultados encontrados enfatizam que os padrões de modularidade observados em distâncias entre marcos são consequência da alometria; linhagens como Homo e Gorilla, que apresentam padrões distintos de modularidade para as distâncias entre marcos estão associados a mudanças substanciais nas relações alométricas dos caracteres cranianos. O último capítulo explora a estrutura filogenética de mudanças nas propriedades variacionais fenotípicas na diversificação de Anthropoidea, considerando apenas variáveis de forma locais, uma vez que este capítulo também visa reforçar os resultados anteriores obtidos a partir de distâncias entre marcos, considerando-se um tipo diferente de representação morfométrica. Este capítulo muda o foco de testes a respeito de padrões de modularidade definidos a priori em direção a estimar a incerteza relacionada à estrutura de matrizes de covariância, decomposta sobre a filogenia de Anthropoidea. Os resultados obtidos demonstram que as mudanças na estrutura de covariância nesta linhagem são localizadas nas mesmas regiões do crânio ao longo de toda a história evolutiva do grupo, enquanto outras regiões mantêm associações estáveis. Assim, quando se considera as diferentes propriedades de representações morfométricas cuidadosamente, inferências feitas a partir de tais representações sobre propriedades variacionais são de fato compatíveis / Modularity is a characteristic property biological systems exhibit regarding the distribution of interactions between their composing elements; in this context, a module is a subset of elements which interact more among themselves than with other subsets. Regarding morphological systems, such property usually refers to the structure of the linear component of the genotype/phenotype map; however, the genetic, developmental, and functional interactions that produce phenotypes are often best described by non-linear dynamics, and a full appreciation of the complexity of such interactions is necessary for understanding phenotypic variational properties. Furthermore, given methodological advances in the field of morphometrics, one may choose different ways to represent morphological variation, and differences between representations may impact inferences made regarding variational properties. The present dissertation aims at exploring the relationship between morphometric representations and the characterization of variational properties, focusing on the comparative analysis of such properties on a macroevolutionary timeframe; Anthropoid Primates are used as a model lineage, given the availability of a large database of skull measurements. This relationship was evaluated under three different perspectives. First, an estimation of the error rates associated with tests for hypothesis that describe modularity patterns related to three different morphometric representations; such evaluation is also associated with an exploration of a subset of the database used here, considering the dynamical properties of developmental interactions that produce the Anthropoid skull. The results of this chapter imply that one of such representations, Procrustes residuals, fails to capture modularity patterns in this setting, considering its particular mathematical underpinnings. Other two representations, interlandmark distances and local shape variables, produce similar results which are directly associated with developmental dynamics, and the differences they exhibit are consistent with their different properties; error rates for tests over both representations are also acceptable. The next chapter deals with comparing these two representations with respect to these different properties, focusing on estimating allometric relationships over local shape variables and the relationship between such estimates and modularity patterns estimated for interlandmark distances. The results found stress out that modularity patterns observed in interlandmark distances are a consequence of allometry; lineages such as Homo and Gorilla, which exhibit distinct modularity patterns in interlandmark distances are associated with substantial changes in allometric relationships for skull traits. The last chapter explores the phylogenetic structure of changes in phenotypic variational properties across Anthropoid diversification, considering local shape variables alone, since this chapter also aims at reinforcing previous results obtained from interlandmark distances, considering a different type of morphometric representation. This chapter shifts the focus from testing a priori-defined modularity patterns to estimating the uncertainty related to covariance matrix structure decomposed over the Anthropoid phylogeny. The results obtained demonstrate that changes in covariance structure on this lineage are localized in the same skull regions across the entire evolutionary history of Anthropoidea, while other regions maintain stable associations. Thus, when one considers the different properties of morphometric representations carefully, inferences made from such representations regarding variational properties are in fact compatible
3

Evolutionary Relationship between Life History and Brain Growth in Anthropoid Primates

Barrickman, Nancy Lynn 18 September 2008 (has links)
<p>The pace of life history is highly variable across mammals, and several evolutionary biologists have theorized that the tempo of a species' life history is set by external factors. These factors, such as food availability and predation pressure, determine mortality rates. In turn, mortality rate determines the age at maturity. High mortality rate results in early age at maturity; individuals must grow and reproduce quickly because of the high risk of death. Conversely, a low mortality rate is allows individuals to prolong their growth period and reproduce slowly. This theory assumes that growth rates are constant across species, and thus body size is determined by mortality rates.</p><p>This project posits that the intrinsic characteristics of species set the pace of life history. Among anthropoids, there is a great deal of variation in growth rates and the pace of life history relative to body size. The hypotheses proposed by this project state that the degree of encephalization in a species determines the growth rates, the length of the growth period, and the adult lifespan. Growing a large brain is costly and requires a prolonged period of development. However, a large brain has the benefit of reducing mortality by facilitating cognitive strategies for food procurement and predator avoidance. This cost/benefit balance results in the pattern of life-history variation in which mortality rates are correlated with the length of the growth period. However, the causal arrows are reversed; instead of the mortality rate determining the age at maturity and consequently the size of the species, the relative brain size of the anthropoid determines the mortality rate and the age maturity.</p><p>These hypotheses were tested by determining the body and brain growth trajectories of thirteen anthropoids, and compiling life-history data from long-term studies of these species in the wild. Multi-variate analyses demonstrated that extensive brain growth, whether through prolonged duration or rapid growth rates, results in slow body-growth rates during the juvenile period and delayed age at maturity. In addition, encephalization results in longer adult lifespan. Therefore, this project demonstrated that intrinsic characteristics of anthropoid species determine the pace of their life histories.</p> / Dissertation
4

Endocranial volume and shape variation in early anthropoid evolution

Allen, Kari Leigh January 2014 (has links)
<p>Fossil taxa are crucial to studies of brain evolution, as they allow us to identify evolutionary trends in relative brain size and brain shape that may not otherwise be identifiable in comparative studies using only extant taxa, owing to multiple events of parallel encephalization among primate clades. This thesis combines indirect and direct approaches to understanding primate evolution, by evaluating variation in the endocranial morphology of extant primates and their fossil representatives. I use a comparative approach to examine the relationships between interspecific adult endocranial volume and shape, and brain evolution and cranial form among extant primate clades and their fossil representatives. The associations are evaluated via phylogenetically informed statistics perfomed on volumetric measurements and three-dimensional geometric morphometric analyses of virtual endocasts constructed from micro-CT scans of primate crania. Fossil taxa included in these analyses are: 1) anthropoids Parapithecus, Aegyptopithecus (Early Oligocene, Egypt), Homunculus and Tremacebus (Early Miocene, Argentina), and 2) Eocene euprimates Adapis and Leptadapis (Eocene adapoids, France), and the Rooneyia (Eocene omomyoid, Texas). </p><p>The first part of this work (Chapter 2) explores variation in residual mass of brain components (taken from the literature) among primates, and evaluates the correlated evolution of encephalization and brain proportions with endocast shape, quantified via three-dimensional geometric morphometric techniques. Analyses reveal a broad range of variation in endocast shape among primates. Endocast shape is influenced by a complex array of factors, including phylogeny, body size, encephalization, and brain proportions (residual mass of brain components). The analysis supports previous research, which concludes that anthropoids and tarsiers (Haplorhini) share the enlargement of several key brain regions including the neocortex and visual systems, and a reduction of the olfactory system. Anthropoids further differ from strepsirrhines in endocranial features associated with encephalization--a more flexed brain base, an inferiorly deflected olfactory fossa--and those associated with brain proportions--a small olfactory fossa, and a more caudally extended cerebrum that extends posteriorly past the cerebellar poles. Tarsiers are unique in having a mediolaterally broad and rostro-caudally short endocast with an attenuated anterior and middle cranial fossae. This morphology is likely related to the extreme orbital enlargement in this taxon, which limits anterior expansion of the endocranium. Finally, despite the correlation between residual endocranial volume and endocast shape among modern primates, early anthropoid fossils demonstrate a disconnect between these factors in sharing key features of endocast shape with extant anthropoids at a relatively small brain size. </p><p>The second part of this thesis (Chapter 3) explores the relationship between craniofacial organization--cranial base angle, facial size, facial hafting--and encephalization via the lens of the Spatial Constraints and Facial Packing Hypotheses. These hypotheses predict that interspecific adult variation in encephalization correlates with endocranial shape such that a larger brain for a given body size will be more "globular" or spherical in shape. These hypotheses futher predict that basicranial angle covaries with encephalization and that the relative size of the endocranium and facial skeleton will have an antagonistic effect on basicranial angle and facial hafting. Results show that various measures of globularity have inconsistent and weak relationships to phylogeny, encephalization, and basicranial flexion, owing to a diversity of clade-specific scaling patterns between the maximum length, breadth, and width of the endocast. Among extant primates, there is weak but significant evidence to suggest that both facial size and encephalization influence variation in basicranial flexion. Considering the fossil specimens in isolation, their relative ranks in encephalization, basicranial flexion, and midline facial size and shape follow the pattern expected from the Spatial and Facial Packing Hypotheses outlined above; however, relative to modern species, the early fossil anthropoids have more flexed cranial bases and shorter facial skeletons at much smaller level of encephalization than seen in modern anthropoids. </p><p>Together, the extant data suggest a moderately conserved pattern of correlated evolution among endocranial size, endocranial shape, brain proportions, and craniofacial organization, which may explain differences in endocranial and facial shape between extant strepsirrhine and anthropoid primates; however, the fossil record for early anthropoid evolution demonstrates that a shift towards key anthropoid-like traits of the endocranium, basicranium, and facial skeleton were initiated early in anthropoid evolution, with subsequent encephalization occurring within and among members of this clade. Thus, these anthropoid cranial traits evolved in tandem with changes in the relative size of brain components, rather than absolute or relative brain size alone. Basicranial flexion, facial length and orientation are influenced by both: 1) shifts in endocranial shape associated with changes in brain proportion--accounting for the initiation of the anthropoid-like craniofacial plan early in the evolution of the clade--and 2) encephalization, which influenced subsequent morphological divergence among extant anthropoid groups.</p> / Dissertation
5

Perspectivas sobre o reconhecimento de padrões de modularidade e suas implicações para a evolução de morfologias complexas / On the recognition of modularity patterns and its implications for the evolution of morphological systems

Guilherme Garcia 07 April 2016 (has links)
A modularidade é uma propriedade característica que sistemas biológicos exibem em relação à distribuição de interações entre seus elementos constituintes; neste contexto, um módulo é um subconjunto de elementos que interagem entre si mais do que com outros subconjuntos. Em relação aos sistemas morfológicos, tais propriedades referem-se geralmente à estrutura do componente linear do mapa genótipo/fenótipo; no entanto, as interações genéticas, ontogenéticas e funcionais que produzem fenótipos são descritas de forma adequada através de dinâmicas não-lineares, e uma apreciação completa da complexidade destas interações é necessária para a compreensão das propriedades variacionais do fenótipo. Ademais, dados avanços metodológicos na área da morfometria, é possível escolher diferentes maneiras de representar a variação morfológica, e as diferenças entre as representações podem impactar inferências feitas sobre estas propriedades variacionais. A presente tese tem como objetivo explorar a relação entre representações morfométricas e a caracterização das propriedades variacionais, focada na análise comparativa de tais propriedades em uma escala macroevolutiva; Primatas Antropóides são utilizados como modelo, dada a disponibilidade de uma grande base de dados de mensurações cranianas destes organismo. Esta relação foi avaliada sob três perspectivas diferentes. Em primeiro lugar, estima-se taxas de erro associadas aos testes de hipótese que descrevem padrões de modularidade, relacionadas com três representações morfométricas distintas; tal avaliação é também associada à exploração de um subconjunto da base de dados utilizada aqui, levando-se em consideração a dinâmica de interações ontogenéticas que produzem o crânio dos Antropóides. Os resultados deste capítulo implicam que uma dessas representações, resíduos de Procrustes, não são capazes de detectar padrões de modularidade neste contexto, considerando suas propriedades matemáticas específicas. Outras duas representações, distâncias entre marcos anatômicos e variáveis locais de forma, produzem resultados semelhantes, que estão diretamente associados à dinâmica de desenvolvimento, e as diferenças que elas apresentam são consistentes com suas diferenças principais; taxas de erro para os testes sobre as duas representações também são aceitáveis. O próximo capítulo trata da comparação entre estas duas representações no que diz respeito a estas diferentes propriedades, focado em estimar relações alométricas associadas às variáveis locais de forma e a relação entre estas estimativas e os padrões de modularidade estimados para distâncias entre marcos anatômicos. Os resultados encontrados enfatizam que os padrões de modularidade observados em distâncias entre marcos são consequência da alometria; linhagens como Homo e Gorilla, que apresentam padrões distintos de modularidade para as distâncias entre marcos estão associados a mudanças substanciais nas relações alométricas dos caracteres cranianos. O último capítulo explora a estrutura filogenética de mudanças nas propriedades variacionais fenotípicas na diversificação de Anthropoidea, considerando apenas variáveis de forma locais, uma vez que este capítulo também visa reforçar os resultados anteriores obtidos a partir de distâncias entre marcos, considerando-se um tipo diferente de representação morfométrica. Este capítulo muda o foco de testes a respeito de padrões de modularidade definidos a priori em direção a estimar a incerteza relacionada à estrutura de matrizes de covariância, decomposta sobre a filogenia de Anthropoidea. Os resultados obtidos demonstram que as mudanças na estrutura de covariância nesta linhagem são localizadas nas mesmas regiões do crânio ao longo de toda a história evolutiva do grupo, enquanto outras regiões mantêm associações estáveis. Assim, quando se considera as diferentes propriedades de representações morfométricas cuidadosamente, inferências feitas a partir de tais representações sobre propriedades variacionais são de fato compatíveis / Modularity is a characteristic property biological systems exhibit regarding the distribution of interactions between their composing elements; in this context, a module is a subset of elements which interact more among themselves than with other subsets. Regarding morphological systems, such property usually refers to the structure of the linear component of the genotype/phenotype map; however, the genetic, developmental, and functional interactions that produce phenotypes are often best described by non-linear dynamics, and a full appreciation of the complexity of such interactions is necessary for understanding phenotypic variational properties. Furthermore, given methodological advances in the field of morphometrics, one may choose different ways to represent morphological variation, and differences between representations may impact inferences made regarding variational properties. The present dissertation aims at exploring the relationship between morphometric representations and the characterization of variational properties, focusing on the comparative analysis of such properties on a macroevolutionary timeframe; Anthropoid Primates are used as a model lineage, given the availability of a large database of skull measurements. This relationship was evaluated under three different perspectives. First, an estimation of the error rates associated with tests for hypothesis that describe modularity patterns related to three different morphometric representations; such evaluation is also associated with an exploration of a subset of the database used here, considering the dynamical properties of developmental interactions that produce the Anthropoid skull. The results of this chapter imply that one of such representations, Procrustes residuals, fails to capture modularity patterns in this setting, considering its particular mathematical underpinnings. Other two representations, interlandmark distances and local shape variables, produce similar results which are directly associated with developmental dynamics, and the differences they exhibit are consistent with their different properties; error rates for tests over both representations are also acceptable. The next chapter deals with comparing these two representations with respect to these different properties, focusing on estimating allometric relationships over local shape variables and the relationship between such estimates and modularity patterns estimated for interlandmark distances. The results found stress out that modularity patterns observed in interlandmark distances are a consequence of allometry; lineages such as Homo and Gorilla, which exhibit distinct modularity patterns in interlandmark distances are associated with substantial changes in allometric relationships for skull traits. The last chapter explores the phylogenetic structure of changes in phenotypic variational properties across Anthropoid diversification, considering local shape variables alone, since this chapter also aims at reinforcing previous results obtained from interlandmark distances, considering a different type of morphometric representation. This chapter shifts the focus from testing a priori-defined modularity patterns to estimating the uncertainty related to covariance matrix structure decomposed over the Anthropoid phylogeny. The results obtained demonstrate that changes in covariance structure on this lineage are localized in the same skull regions across the entire evolutionary history of Anthropoidea, while other regions maintain stable associations. Thus, when one considers the different properties of morphometric representations carefully, inferences made from such representations regarding variational properties are in fact compatible
6

Atentát na říšského protektora Reinharda Heydricha - komparace filmových adaptací Atentát (1964) a Anthropoid (2016) / Assassination of Reichsprotektor Reinhard Heydrich - comparison of movie adaptations Atentát (1964) and Anthropoid (2016)

Majerová, Marie January 2018 (has links)
Diploma thesis with the title Atentát na říšského protektora Reinharda Heydricha - komparace filmových adaptací Atentát (1964) a Anthropoid (2016) deals with the influence of selected factors on the movie representation of real historical event. These facts can be the time and the country of origin, the political situation in the country, the target market, nationality of the authors, etc. The theoretical part will present the historical context of the real event, the corresponding film theory, artistic means and methodology. The comparative analysis will help to compare pre-selected scenes and situations identical for both movies. The findings will be evaluated at the end of the thesis.
7

Philistine burial practices in cultural context

Fugitt, Stephen Mark 30 November 2003 (has links)
This paper traces burials from Iron Age I Canaan that reflect an influence of Philistine culture. This influence can be measured by the presence of Philistine bichrome pottery or other evidence related to this ancient biblical people. A major road block to the clearest possible understanding of Philistine burials is that no cemeteries have been found at any of the earliest settlements of the biblical Philistines, the Pentapolis. The Old Testament lists these cities as Ashkelon, Ashdod, Ekron, Gath, and Gaza (e.g. Joshua 13:3). Though extensive excavation has been conducted at most of these sites, they have yet to yield a necropolis. Excavations are still being done at Tell es-Safi/Gath and Ashkelon, so hopefully the future will supply researchers with data to help clarify this rather vague area of Philistine studies. Recognizing these limitations, the paper presents a "symbiotic model," which identifies some of the areas of shared culture from the Canaanite context. Examples of this symbiosis are seen as the amalgamated result of people groups living in close proximity to each other and influencing the customs and practices of their neighbors. A Mycenaean origin of the Philistines is an underlying supposition of the research laid out in this paper. Because of this origin, and the other influences upon the early Philistine settlers in Canaan, a certain amount of cultural comparison becomes necessary to be able to understand the developing Philistine culture of Iron I. The paper includes a map of tombs and burials bearing Philistine influence and a map identifying different types of tombs and their locations. The variety of tomb types is an important facet of Philistine custom. The strong Egyptian influence upon Canaan and the surrounding area at that time in history is inescapable. Evidence of this influence will be explored. The inclusion of a chapter on the anthropoid clay coffins, and the Philistines' relationship to them, struggles with the scholarly interpretations. Finally, a chapter on literary implications strives to shed light on possible Philistine burial practices from the perspective of the Old Testament and other applicable literatures of the ancient Near East. / Old Testament / D. Th.
8

Philistine burial practices in cultural context

Fugitt, Stephen Mark 30 November 2003 (has links)
This paper traces burials from Iron Age I Canaan that reflect an influence of Philistine culture. This influence can be measured by the presence of Philistine bichrome pottery or other evidence related to this ancient biblical people. A major road block to the clearest possible understanding of Philistine burials is that no cemeteries have been found at any of the earliest settlements of the biblical Philistines, the Pentapolis. The Old Testament lists these cities as Ashkelon, Ashdod, Ekron, Gath, and Gaza (e.g. Joshua 13:3). Though extensive excavation has been conducted at most of these sites, they have yet to yield a necropolis. Excavations are still being done at Tell es-Safi/Gath and Ashkelon, so hopefully the future will supply researchers with data to help clarify this rather vague area of Philistine studies. Recognizing these limitations, the paper presents a "symbiotic model," which identifies some of the areas of shared culture from the Canaanite context. Examples of this symbiosis are seen as the amalgamated result of people groups living in close proximity to each other and influencing the customs and practices of their neighbors. A Mycenaean origin of the Philistines is an underlying supposition of the research laid out in this paper. Because of this origin, and the other influences upon the early Philistine settlers in Canaan, a certain amount of cultural comparison becomes necessary to be able to understand the developing Philistine culture of Iron I. The paper includes a map of tombs and burials bearing Philistine influence and a map identifying different types of tombs and their locations. The variety of tomb types is an important facet of Philistine custom. The strong Egyptian influence upon Canaan and the surrounding area at that time in history is inescapable. Evidence of this influence will be explored. The inclusion of a chapter on the anthropoid clay coffins, and the Philistines' relationship to them, struggles with the scholarly interpretations. Finally, a chapter on literary implications strives to shed light on possible Philistine burial practices from the perspective of the Old Testament and other applicable literatures of the ancient Near East. / Biblical and Ancient Studies / D. Th.

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