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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.
41

Using MORPHOMETRICS, Phylogenetic Systematics and Parsimony Analysis to Gain Insight into the Evolutionary Affinities of the Calymenidae Trilobita

Chestnut, Alex J. 14 May 2009 (has links)
No description available.
42

Reconstruindo parentesco e desfazendo preconceitos: filogenia de Gonyleptidae (Arachnida, Opiliones) usando caracteres ecológicos, comportamentais e químicos / Phylogeny of Gonuyleptidae (Arachnida, Opiliones) using ecological, behavioral and chemical characteres

Silva, Daniel Caetano da 26 May 2011 (has links)
A ordem Opiliones contém cerca de 6000 espécies divididas em quatro subordens e 45 famílias. Dentre essas famílias, os Gonyleptidae se destacam por sua enorme diversidade e por concentrarem a maioria dos estudos sobre biologia de opiliões. Este estudo, valeu-se dessa grande disponibilidade de informações ecológicas, comportamentais e químicas para reconstruir as relações de parentesco entre as subfamílias de Gonyleptidae. Posteriormente, com base nas topologias obtidas, discutimos os padrões de evolução dessas características dentro da família. A listagem de terminais compreende 31 espécies, sendo 27 representantes do grupo-interno e quatro do grupo-externo (Stygnidae, Manosbiidae e Cosmetidae). O grupo-interno é composto por representantes de 14 das 16 subfamílias de Gonyleptidae, exceto Ampycinae e Gonyassamiinae. Realizamos a análise filogenética utilizando caracteres igualmente pesados e os algoritmos de pesagem sucessiva e implícita. Levantamos 48 caracteres e 72 estados derivados, o que faz deste trabalho a maior matriz de caracteres ecológico-comportamentais já publicada até o momento. A análise com pesos iguais gerou uma árvore de consenso menos resolvida, porém compatível com a única topologia obtida com pesagem sucessiva e uma de duas topologias estáveis obtidas utilizando a pesagem implícita. Considerando apenas as análises com pesagem sucessiva e implícita, Gonyleptidae aparece como um grupo monofilético, irmão de Cosmetidae e definido por uma sinapomorfia inequívoca (brigas entre machos usando as pernas IV). Dentre as subfamílias já revisadas e que aqui contaram com mais de um terminal, recuperamos o monofiletismo de cinco delas: Hernandariinae, Goniosomatinae, Mitobatinae, Tricommatinae e Heteropachylinae. Não obtivemos apoio ao monofiletismo de Gonyleptinae, Sodreaninae e Progonyleptoidellinae. Dentre os grandes grupos tradicionalmente reconhecidos dentro de Gonyleptidae, obtivemos apoio ao clado formado por Hernandariinae + Gonyleptinae + Sodreaninae + Progonyleptoidellinae + Caelopyginae. Os altos valores dos índices de consistência das árvores, associado aos altos valores de suporte obtidos para vários clados (especialmente subfamílias), indicam que comportamento e ecologia são fontes de caracteres filogeneticamente informativos e que devem ser considerados em estudos futuros com a família. Embora caracteres ecológico-comportamentais já tenham sido utilizados em estudos cladísticos anteriores, esta é a primeira vez que o monofiletismo de uma família de Arthropoda é formalmente definido exclusivamente com base em caracteres de natureza não morfológica ou molecular. / The order Opiliones has almost 6000 species divided in four suborders and 45 families. Among these families, Gonyleptidae is well-known by its high diversity and because it concentrates the majority of the publications on harvestman ecology and behavior. We took advantage of this information to reconstruct the phylogeny of the gonyleptid subfamilies and discuss evolutionary patterns within the family based on the resulting topologies. The terminal species include 31 taxa, four belonging to the external-group (Stygnidae, Manosbiidae, and Cosmetidae), and 27 to the internal-group, which contains representatives of 14 of the 16 gonyleptid subfamilies (except Ampycinae and Gonyassamiinae). We performed the analyses using three distinct weighting schemes: equally weighted characters, successive weighting, and implied weighting. We coded 48 characters comprising 72 derived states, which makes the present study the largest ecological and behavioral phylogenetic data matrix published so far. The equal weighted analysis resulted in a single poorly resolved consensus tree, but this tree was compatible with the single most parsimonious successive weighted tree and with one of the two most stable trees obtained with implied weighting. Considering only the non-linear weighting schemes, Gonyleptidae is a monophyletic group, sister to Cosmetidae, based on a single non-homoplastic behavioral synapomorphy (male fights using the fourth pair of legs). We recovered the monophyly of five subfamilies that have already been revised using morphological characters: Hernandariinae, Goniosomatinae, Mitobatinae, Tricommatinae, and Heteropachylinae. We also obtained support for a well-recognized clade composed of the subfamilies Hernandariinae, Gonyleptinae, Sodreaninae, Progonyleptoidellinae, and Caelopyginae. However, we did not find support for the monophyly of Gonyleptinae, Sodreaninae, and Progonyleptoidellinae. High consistence indexes, in association with high Bremer and bootstrap support values for several clades (mainly subfamilies), clearly indicate that behavior and ecology provide phylogenetically informative characters. For that reason, they should be considered in future phylogenetic studies within Opiliones. Even though behavioral and ecological characters have already been used in other cladistic studies, this is the first time that the monophily of an arthropod family is formally demonstrated using exclusively non-morphological or non-molecular characters.
43

Reconstruindo parentesco e desfazendo preconceitos: filogenia de Gonyleptidae (Arachnida, Opiliones) usando caracteres ecológicos, comportamentais e químicos / Phylogeny of Gonuyleptidae (Arachnida, Opiliones) using ecological, behavioral and chemical characteres

Daniel Caetano da Silva 26 May 2011 (has links)
A ordem Opiliones contém cerca de 6000 espécies divididas em quatro subordens e 45 famílias. Dentre essas famílias, os Gonyleptidae se destacam por sua enorme diversidade e por concentrarem a maioria dos estudos sobre biologia de opiliões. Este estudo, valeu-se dessa grande disponibilidade de informações ecológicas, comportamentais e químicas para reconstruir as relações de parentesco entre as subfamílias de Gonyleptidae. Posteriormente, com base nas topologias obtidas, discutimos os padrões de evolução dessas características dentro da família. A listagem de terminais compreende 31 espécies, sendo 27 representantes do grupo-interno e quatro do grupo-externo (Stygnidae, Manosbiidae e Cosmetidae). O grupo-interno é composto por representantes de 14 das 16 subfamílias de Gonyleptidae, exceto Ampycinae e Gonyassamiinae. Realizamos a análise filogenética utilizando caracteres igualmente pesados e os algoritmos de pesagem sucessiva e implícita. Levantamos 48 caracteres e 72 estados derivados, o que faz deste trabalho a maior matriz de caracteres ecológico-comportamentais já publicada até o momento. A análise com pesos iguais gerou uma árvore de consenso menos resolvida, porém compatível com a única topologia obtida com pesagem sucessiva e uma de duas topologias estáveis obtidas utilizando a pesagem implícita. Considerando apenas as análises com pesagem sucessiva e implícita, Gonyleptidae aparece como um grupo monofilético, irmão de Cosmetidae e definido por uma sinapomorfia inequívoca (brigas entre machos usando as pernas IV). Dentre as subfamílias já revisadas e que aqui contaram com mais de um terminal, recuperamos o monofiletismo de cinco delas: Hernandariinae, Goniosomatinae, Mitobatinae, Tricommatinae e Heteropachylinae. Não obtivemos apoio ao monofiletismo de Gonyleptinae, Sodreaninae e Progonyleptoidellinae. Dentre os grandes grupos tradicionalmente reconhecidos dentro de Gonyleptidae, obtivemos apoio ao clado formado por Hernandariinae + Gonyleptinae + Sodreaninae + Progonyleptoidellinae + Caelopyginae. Os altos valores dos índices de consistência das árvores, associado aos altos valores de suporte obtidos para vários clados (especialmente subfamílias), indicam que comportamento e ecologia são fontes de caracteres filogeneticamente informativos e que devem ser considerados em estudos futuros com a família. Embora caracteres ecológico-comportamentais já tenham sido utilizados em estudos cladísticos anteriores, esta é a primeira vez que o monofiletismo de uma família de Arthropoda é formalmente definido exclusivamente com base em caracteres de natureza não morfológica ou molecular. / The order Opiliones has almost 6000 species divided in four suborders and 45 families. Among these families, Gonyleptidae is well-known by its high diversity and because it concentrates the majority of the publications on harvestman ecology and behavior. We took advantage of this information to reconstruct the phylogeny of the gonyleptid subfamilies and discuss evolutionary patterns within the family based on the resulting topologies. The terminal species include 31 taxa, four belonging to the external-group (Stygnidae, Manosbiidae, and Cosmetidae), and 27 to the internal-group, which contains representatives of 14 of the 16 gonyleptid subfamilies (except Ampycinae and Gonyassamiinae). We performed the analyses using three distinct weighting schemes: equally weighted characters, successive weighting, and implied weighting. We coded 48 characters comprising 72 derived states, which makes the present study the largest ecological and behavioral phylogenetic data matrix published so far. The equal weighted analysis resulted in a single poorly resolved consensus tree, but this tree was compatible with the single most parsimonious successive weighted tree and with one of the two most stable trees obtained with implied weighting. Considering only the non-linear weighting schemes, Gonyleptidae is a monophyletic group, sister to Cosmetidae, based on a single non-homoplastic behavioral synapomorphy (male fights using the fourth pair of legs). We recovered the monophyly of five subfamilies that have already been revised using morphological characters: Hernandariinae, Goniosomatinae, Mitobatinae, Tricommatinae, and Heteropachylinae. We also obtained support for a well-recognized clade composed of the subfamilies Hernandariinae, Gonyleptinae, Sodreaninae, Progonyleptoidellinae, and Caelopyginae. However, we did not find support for the monophyly of Gonyleptinae, Sodreaninae, and Progonyleptoidellinae. High consistence indexes, in association with high Bremer and bootstrap support values for several clades (mainly subfamilies), clearly indicate that behavior and ecology provide phylogenetically informative characters. For that reason, they should be considered in future phylogenetic studies within Opiliones. Even though behavioral and ecological characters have already been used in other cladistic studies, this is the first time that the monophily of an arthropod family is formally demonstrated using exclusively non-morphological or non-molecular characters.
44

Evolution of the Orthoptera: systematic placement among insects, internal phylogeny and the origin of bioacoustics

Leubner, Fanny 07 July 2017 (has links)
No description available.
45

Phylogénie moléculaire de Monopetalanthus Harms (Fabaceae: Caesalpinioideae) et des genres affiliés

Gervais, G. Y. Fannie January 2000 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
46

Phylogeny, diversity, and ecology of the ammonoid superfamily Acanthoceratoidea through the Cenomanian and Turonian

Mertz, David A.A. 02 August 2017 (has links)
No description available.
47

New insights into old problems : the application of a multidisciplinary approach to the study of early Egyptian ceramic chronology, with a focus on luminescence dating

Hood, Amber Giles Eve January 2016 (has links)
This thesis takes a multidisciplinary approach to the study of ancient Egyptian ceramics by applying scientific dating techniques alongside more traditional methods. It is the first study to apply OSL dating to an Egyptian ceramic assemblage, and it has done so by developing the minimum extraction technique (MET), which has made it possible to use OSL to sample, and thus analyse, ceramics housed in museums. The MET is at present essential to the success of OSL dating of Egyptian ceramics, as the exportation ban on antiquities has prevented OSL analysis of field material. For this thesis, using this new sampling technique, OSL has been applied to several assemblages from the Predynastic to the Early Dynastic period. Ceramics from [ADD IN REVIEW ] have been examined, with three phases being established: late Naqada III, First Intermediate Period, and the mediaeval Islamic period. Absolute dates have been determined for each phase and, where comparison is possible, have been found in good agreement with the historical chronology. A set of vessels from Naqada, Ballas, and the Tomb of Djer at Abydos have been examined using OSL in conjunction with radiocarbon dating. Again, three phases of activity were discerned: late Naqada II, early Naqada III, and the first scientifically determined dates for a burning event in the Tomb of Djer (the New Kingdom). The thesis also demonstrates how OSL can be used as a relative dating technique by analysing a collection of Wavy-Handled ceramics and wine jars from Turah, finding that the OSL results agree well with the established relative chronology. Finally, this thesis has also examined the applicability of cladistic analysis to the study of Egyptian ceramics. Cladistics is a technique borrowed from the biological sciences which offers a complimentary way to examine the evolution of ceramic types and forms, in particular the development of beer and wine jars.
48

Evolution des sauropodomorphes basaux et diversification des dinosaures sauropodes : apport des faunes du Lesotho et cladistique comparée / Evolution of basal sauropodomorphs and diversification of sauropod dinosaurs : contribution of Lesotho's fauna and comparative cladistics

Peyre de Fabrègues, Claire 11 October 2016 (has links)
L’évolution des dinosaures sauropodomorphes et la radiation des grands sauropodes sont encore loin d'être comprises, ni même datées avec précision. Si les premiers sauropodes semblent apparaître à la fin du Trias, ils ne se diversifient qu'à partir du Jurassique moyen. L’incertitude entourant la définition à donner au clade Sauropoda est une des principales causes de l'absence de consensus quant à la transition prosauropodes – sauropodes. C’est ce problème du « stem-group » des sauropodes qui est abordé dans cette thèse. Certains prosauropodes sont ainsi aujourd’hui considérés comme des sauropodes à part entière par certains auteurs. Ces taxons basaux diffèrent cependant beaucoup selon les auteurs. La multiplication des analyses cladistiques n’a rien résolu puisque celles-ci n’ont jamais été comparées entre elles.La découverte en 2008, par une équipe du MNHN, dans le Jurassique inférieur du Lesotho, d'un squelette de prosauropode articulé sert ici de base à une étude anatomique et systématique des sauropodomorphes basaux. De nombreux autres restes de dinosaures inédits du Lesotho appartenant aux collections du MNHN viennent compléter le matériel d’étude. Parmi ceux-ci, du matériel rapporté au prosauropode de Maphutseng et des fossiles attribués au genre Meroktenos sont entièrement décrits en détail pour la première fois.Une comparaison critique et détaillée des analyses phylogénétiques antérieures a été réalisée en utilisant la méthode de cladistique comparée telle qu’elle a été formalisée par Sereno en 2009. Elle a permis de démontrer l’impact très important du choix des caractères et de leur codage sur la topologie des arbres. Suite à cela, un premier retour sur une liste compilée de 449 caractères a été effectué. Il a nécessité la vérification d’une matrice de 15 000 à 20 000 cellules, et plus de 1300 mesures. Ce retour aux caractères ont entraîné la suppression de plus d’une centaine de caractères, et la création d’une matrice inédite de 49 unités taxonomiques et 308 caractères. Les résultats de l’analyse phylogénétique de cette matrice, bien que préliminaires, soulèvent plusieurs points intéressants. Plusieurs clades, généralement retrouvés dans les analyses les plus récentes publiées par d’autres auteurs, n’apparaissent pas. En revanche, des clades qui n’avaient jusque-là jamais été retrouvés font leur apparition. Les différentes analyses pointent également du doigt le problème de l’origine des Sauropodomorpha, et relancent le débat sur l’origine du clade Sauropoda. / The evolution of sauropodomorph dinosaurs and the radiation of the large sauropods are still far from being understood and well-dated. If the first sauropods seem to appear at the end of the Triassic, they don’t start to diversify before the Middle Jurassic. The uncertainty surrounding the definition of the clade Sauropoda is one of the main causes of the lack of consensus regarding the prosauropod – sauropod transition. It is this issue of the “stem-group” of sauropods that is dealt with in this thesis. Some prosauropods are now considered to be sauropods by some authors. These basal taxa differ a lot depending on the authors. The multiplication of the cladistic analyses didn’t solve the problem as they never were compared.The discovery in 2008, by a MNHN team, in the Early Jurassic of Lesotho, of a prosauropod articulated skeleton is used herein as the basis for anatomical and systematic study of basal sauropodomorphs. Many other new dinosaur remains from Lesotho, housed in the MNHN collections, complement the study material. Among these, material referred to the Maphutseng prosauropod and fossils referred to the genus Meroktenos are described in details for the first time.A critical and detailed comparison of previous phylogenetic analyses is performed, using the comparative cladistics method as formalized by Sereno in 2009. This work allowed to highlight the significant impact of the choice of characters and their scoring on the topology of the trees. After that, a first reappraisal of a list of 449 compiled characters was carried out. It required the reexamination of a matrix consisting in 15 000 to 20 000 cells, and more than 1300 measures. This work led to remove more than one hundred morphological characters, and the building of a new matrix including 49 taxonomic units and 308 characters. The results of the phylogenetic analysis, although preliminary, raise some interesting points. Several clades, often recovered in the most recent analyses published by other authors, are not recognized here. However, clades that had, until then, never been found, are recovered. The different analyses also point out the hurdle of the origin of Sauropodomorpha, and reopen the debate on the origin of Sauropoda.
49

Systematics and Evolution of the Californian Trapdoor Spider Genus Aptostichus Simon (Araneae: Mygalomorphae: Euctenizidae)

Bond, Jason E. 28 September 1999 (has links)
Chapter One: Raven's 1985 phylogenetic analysis of the Mygalomorphae placed a number of previously unrelated genera into the rastelloid family Cyrtaucheniidae. Although Goloboff's 1993 reanalysis of mygalomorph relationships retained the familial composition of the Rastelloidina it di not support cyrtaucheniid monophyly. This study resolves the issue of cyrtaucheniid monophyly within the context of the Rastelloidina. Using 71 morphological characters scored for 29 mygalomorph taxa we find that the Cyrtaucheniidae is polyphyletic and propose the following families in its place: Cyrtaucheniidae, Kiamidae (new family), Aporoptychidae (new rank), Ancylotrypidae (new family) and Euctenizidae (new rank). We also propose two new euctenizid genera, Apachella and Sinepedica, revise the taxonomy of the euctenizids of the Southwestern United States, and present a key for these six genera. In addition to the morphologically based phylogeny we test and refine the euctenizid intergeneric phylogeny using molecular data (mitochondrial 16S rRNA and COI genes and 28S rRNA nuclear genes). The results of the combined morphological and molecular analysis are used to construct a composite rastelloid phylogeny that is used to investigate biogeographical relationships, burrow entrance evolution, and homoplasy. Chapter Two: This systematic study of the predominately Californian trapdoor spider genus Aptostichus Simon, 1890 describes 28 species, 25 of which are newly described: A. atomus, A. improbulus, A. insulanus, A. icenoglei, A. ebriosus, A. muiri, A. cahuillus, A. luiseni, A. serranos, A. calientus, A. chemehuevi, A. shoshonei, A. pauitei, A. tipai, A. cochesensis, A. indegina, A. gertschi, A. kristenae, A. fornax, A. spinaserratus, A. brevifolius, A. brevispinus, A. agracilapandus, A. tenuis, and A. gracilapandus. Aptostichus stanfordianus Smith, 1908 is considered to be a junior synonym of A. atomarius Simon 1890. Using 72 quantitative and qualitative morphological characters we propose a preliminary phylogeny for this group. Based on the results of this phylogenetic analysis, we recognize the Atomarius, Simus, Hesperus and Pandus species groups. Additionally, our phylogenetic analysis indicates that adaptations favoring the invasion of the very arid desert habitats of southern California have evolved multiple times in the Aptostichus clade. The existence of both desert and non - desert species in three of the four species groups makes this genus an ideal candidate for the study of the evolutionary ecology of desert arthropods. Chapter Three: Aptostichus simus is a trapdoor spider that is endemic to the coastal dunes of southern California and is recognized as a single species on morphological grounds. Mitochondrial DNA 16S rRNA sequences demonstrate that populations from San Diego County, Los Angeles County, Santa Rosa Island, and Monterey County are extremely divergent (6 - 12%). These results are comparable to, or higher than recent reports of species - level differences in other invertebrate taxa. A molecular clock hypothesis shows that these four populations have been separated for 2 - 6 million years. A statistical cluster analysis of morphological features demonstrates that this genetic divergence is not reflected in anatomical features that might signify ecological differentiation among these lineages. The species status of these divergent populations of A. simus depends upon the species concept utilized. The time - limited genealogical perspective that is employed separates A. simus into two genetically distinct species. This study suggests that a species concept based on morphological distinctiveness in spider groups with limited dispersal capabilities probably underestimate taxonomic diversity. / Ph. D.
50

Phylogenetische Untersuchungen an Schädeln der Neuweltaffen (Platyrrhini) / Phylogenetic investigations of skulls of the New World monkeys (Platyrrhini)

Wiesemüller, Bernhard 27 January 2005 (has links)
No description available.

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