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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.
191

Análise e comparação tafonômica-paleoecológica de três assembléias triássicas do Rio Grande do Sul

Macedo, Marcia Raquel Pegoraro de 26 February 2008 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-05-11T11:17:51Z No. of bitstreams: 1 marciaraquelpegorarodemacedo.pdf: 5847098 bytes, checksum: 6cf16b9ed061b6daffde11584b9e8e4e (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-11T13:25:30Z (GMT) No. of bitstreams: 1 marciaraquelpegorarodemacedo.pdf: 5847098 bytes, checksum: 6cf16b9ed061b6daffde11584b9e8e4e (MD5) / Made available in DSpace on 2017-05-11T13:25:30Z (GMT). No. of bitstreams: 1 marciaraquelpegorarodemacedo.pdf: 5847098 bytes, checksum: 6cf16b9ed061b6daffde11584b9e8e4e (MD5) Previous issue date: 2008-02-26 / A paleontologia do Rio Grande do Sul é conhecida principalmente pelos estudos de materiais triássicos que começaram no século passado, com as expedições de Von Huene e Price nas décadas de 20 e 40, por exemplo. Desde então novos afloramentos são constantemente descobertos e nestes, destaca-se uma variada paleofauna. Nesta paleofauna, os arcossauros, rincossauros, cinodontes, dicinodontes e procolofonídeos são os grupos mais representativos e mais estudados, com enfoque principalmente na sua morfologia, sistemática e evolução. Entretanto, pouca atenção é dada aos aspectos paleoecológicos destes grupos. Assim, este trabalho visa descrever a tafonomia e caracterizar a paleoecologia de três sítios fossilíferos do Triássico Médio do Rio Grande do Sul – Cortado, Linha Várzea e Picada do Gama. A partir da integração de dados obtidos do material coletado até o momento pode se chegar a algumas conclusões específicas sobre cada assembléia, bem como sobre a representatividade paleoecológica destas para o período temporal que compreende a Cenozona de Therapsida. A quantificação e caracterização tafonômica dos elementos ósseos e coprólitos tiveram um importante papel para a diagnose das assembléias estudadas, visto que representaram tanto a paleofauna quanto às características paleoambientais da época. Inferiu-se que a mortandade ocorrente nos sítios estudados foi natural (doença ou predação) e as assembléias formaram-se por eventos de sedimentação gradual, permitindo: a preservação de diferentes estágios ontogenéticos e de icnofósseis característicos de diferentes grupos e condições ambientais, bem como a preservação de características aleoclimatológicas do local. O Sítio Cortado e Linha Várzea representam assembléias autóctones, enquanto o Sítio Picada do Gama apresenta assembléia para-autóctone com alguns elementos bem preservados autóctones. Os Sítios Linha Várzea e Cortado são característicos de planícies de inundação e o Sítio Picada da Gama é característico de depósito de canal. Os padrões de fragmentação e o alto nível de desarticulação dos fósseis indicam período prolongado de exposição ao intemperismo e alterações eodiagenéticas. As proporções de herbívoros e carnívoros presentes em todos afloramentos indicam que os padrões de controle trófico de cadeias alimentares já apresentavam modelos complexos bem estabelecidos baseados em grandes biomassas de herbívoros sustentando carnívoros de topo. Na Cenozona de Therapsida, a base das cadeias alimentares se dava pela presença de dicinodontes como consumidores primários (herbívoros) e arcossauros no topo (carnívoros). Os cinodontes, apesar de apresentarem especializações alimentares, não foram atribuídos a nenhuma posição na cadeia, pois de acordo com a disponibilidade de alimentos, esses animais seriam menos seletivos, e, dependendo da época do ano, poderiam se comportar como oportunistas, ocupando diversas posições dentro das cadeias alimentares. / The paleontology of the Rio Grande do Sul state, southern Brazil, is known mainly by the studies of Triassic materials that had initiated in the beginning of the 20th century with the expeditions of Von Huene and Price in the decades of 20 and 40, respectively. Since then, new outcrops constantly are discovered, some of them with a rich paleofauna. In this paleofauna, the archosaurs, rhynchosaurs, cynodonts, dicynodonts and procolophonids are the most representative and more studied groups, mainly in its morphology, systematic and evolution. However, little attention is given to the paleoecological aspects of these groups. Thus, this work aims to describe the taphonomy and the paleoecology of three outcrops of the Middle Triassic of the RS – Cortado, Linha Várzea and Picada do Gama. By integrating the material collected until the moment, some specific conclusions for each assembly can be achieved, as well as on the paleoecological representation of these for the time period that contains the Therapsida Cenozone. The quantification and taphonomical characterization of the bones and coprolites had an important role for diagnosing the studied outcrops, as they record both paleofaunistic and paleoenvironmental features. The mortality of the studied outcrops was natural (disease or predation) and the assemblies had formed through time, allowing the preservation of: different ontogenetical stages; ichnofossils of different groups and environmental conditions; and paleoclimatological features of the place. The Cortado and Linha Várzea outcrops represent autochthonous assemblages while the Picada do Gama outcrop presents a para-autochthonous assemblage, with some well preserved autochthonous elements. The Cortado and Linha Várzea outcrops are characteristic of distal flooding plains and the Picada do Gama outcrop records both channel deposits and proximal flooding plain facies. The pattern of fossil fragmentation and the high level of disarticulation indicate a prolonged period of exposition to weathering and superficial eodiagenetic alterations. The rate of herbivorous and carnivores in all outcrops indicate that the patterns of trophic control of the food chains already showed complex models, established in great biomasses of herbivorous supporting carnivorous on top. In the Therapsida Cenozone, the food chains bases are represented by first-level consumer dicynodonts (herbivorous) and archosaurs in the top (carnivorous). Cynodonts, although presenting food specializations, had not been attributed to any position in the chain, as these animals would be less selective, and depending on the time of the year, they could behave as opportunists, occupying diverse positions inside of the food chains.
192

Arqueologia da Morte no sítio Hatahara durante a fase paredão / Archaeology of death in the Site Hatahara during the Paredão Phase

Anne Rapp Py-Daniel 17 December 2009 (has links)
O sítio Hatahara, município de Iranduba/AM, vem sendo estudado desde 1999 e já foi alvo de diversos trabalhos acadêmicos (Machado, 2005; Neves e Petersen, 2006; Tamanaha, 2006; Rebellato, 2007; Lima, 2008 e outros). Esse sítio é excepcional por diversas razões: tamanho, conteúdo, número de ocupações, montículos construídos e principalmente estado de conservação do material orgânico (humano, animal e vegetal). Nesse trabalho optou-se por fazer uma análise mais aprofundada dos sepultamentos pertencentes à fase Paredão (séculos VII a XII) oriundos desse sítio. O objetivo sendo o de obter mais informações sobre as escolhas das comunidades pretéritas, os gestos funerários e o contexto no qual eles se inseriam. Os dados adquiridos através da perspectiva da arqueologia da morte e pela tafonomia estão sendo comparados aos trabalhos já produzidos sobre esse local. Como resultado percebe-se um padrão funerário complexo com variações significativas e estruturas polivalentes (funerárias e habitacionais). Além disso, percebeu-se que a conservação dos materiais orgânicos estão intimamente relacionados a certas variáveis ambientais e culturais que permitem envisajar que mais sítios arqueológicos nessas condições possam ser descobertos na Amazônia. / The Hatahara site, in Iranduba, State of Amazonas, has been studied since 1999 and was at the heart of many papers (Machado, 2005; Neves e Petersen, 2006; Tamanaha, 2006; Rebellato, 2007; Lima, 2008 and others). This site is exceptional for several raisons: size, content, number of occupations, earth mounds and mainly state of conservation of organic material (human, animal and vegetal). For this project it was decided that a more thorough analyses should be conducted on the burials belonging to the Paredão phase (7th to 13th century) found in this site. The main purpose was to obtain information on the life of past societies, funerary rituals and the context in which they were inserted. The data acquired through the perspective of the archaeology of death and taphonomy are being compared to the work already produced about this site. As a result we noticed a complex funerary pattern with meaningful variations and multi-purpose structures (funerary and habitation). Furthermore, it was observed that the preservation of organic materials was closely related to certain environmental and cultural variables that allow us to expect that more archaeological sites having these conditions may be discovered.
193

La faune holocène en Tunisie : études paléontologique, archéozoologique, taphonomique et paléoenvironnements / Holocene fauna in Tunisia : archeozoological, taphonomic and paleoenvironmental studies

Dridi Ayari, Yosra 10 April 2015 (has links)
Le changement climatique au cours de l’Holocène est un événement majeur, qui a bien influencé sur le développement d’activité de subsistance. Cette interaction entre l’Homme et son environnement a pu être aperçu par l’analyse de la faune de quatre gisements étendus chronologiquement du Capsien au Néolithique. Les gisements BH et SHM1, reflètent une vie fondée sur la chasse, la pêche et la collecte des escargots terrestres. Les gisements les plus récents sont ceux K.Ag et DK, traduisent le passage à une activité de production manifesté par l’élevage des ovicaprins, sans exclure l’apport de la chasse et de la pêche dans l’alimentation des occupants. Les bovidés ont été toujours la source principale dans leur apport alimentaire, mais avec une dominance de mouflon à manchettes à BH, de l’antilope bubale à SHM1 et des Caprini domestiques dans les deux gisements néolithiques (K.Ag et DK). La présence des Caprini domestiques était antérieure à celle des bovins. La fréquence du mouton par rapport à la chèvre était observée dans les deux sites néolithiques.L’étude archéozoologique illustre une faible présence des parties squelettiques les plus nutritives suite à une forte intensité anthropique, dans tous les sites. La richesse spécifique ainsi que la variabilité spécifique est à l’origine de la nature du climat ainsi qu’à la position géographique du site. / Climate change during the Holocene is a major event. It had a great influence on the development of the movement of subsistence. This interaction between human being and his environment may be seen by the analysis of faunal remains of four deposits chronologically extended from Caspian to Neolithic.Both BH and SHM1 deposits, reflect a way of life based on hunting, fishing and the collection of land snails. The most recent deposits, are of K.Ag and DK, translates the move to an activity of production shown by the goat breeding, without excluding the contribution of hunting and fishing of the occupants’ food supply.The Bovids has been always the main source of their own food intake, but with the dominance of the barbary sheep in BH, the hartebeest to SHM1 and domestic goats within the two Neolithic deposits (K.Ag and DK).The presence of the local ovicaprids preceded the cattle. The frequency of sheep versus goats was observed within the two Neolithic sites.The Archeozoologic study illustrates a weak presence of the most nutritious skeletal elements after a strong intensive anthropic in all sites. The Specific richness as well as the specific variable is the origin of the climatic nature even the geographic position of the site.
194

Semikvantitativní zhodnocení fosilní asociace dobrotivského souvrství (ordovik pražské pánve) na lokalitě Ejpovice / Semiquantitative study of the fossil association of the Dobrotivá Formation (Ordovician, Prague Basin) in Ejpovice

Luptáková, Monika January 2021 (has links)
The master thesis is focused on the semiquantitative study of the fossil association of the stratigraphically lowest layer No. 3 from the channel sample from the Ejpovice locality, where in the southern bank of the flooded quarry, the Dobrotivá Formation of the Ordovician of the Prague Basin is exposed in the thickness of several meters. The thesis briefly summarizes basic knowledge about the fossil associations of the Dobrotivá Formation, its lithology, stratigraphy and previous paleontological research at studied locality. Paleoecology of the fauna recorded in studied material is described. The main part of the thesis is focused on the taphonomy and associations of the fossils recorded in studied material. In the final part of the thesis, the overall fossil association is characterized depending on the paleoecology and taphonomy of preserved fossils, and the model of the paleoenvironment at the Ejpovice locality is discussed. Based on the lithology and studied fossil associations, it is assumed that a dysoxic environment with episodic currents prevailed in the Ejpovice locality. The fauna is species-depleted and taxa typical of the Dobrotivá Formation are rare. The fauna is mainly allochtonous and most of the organisms are considered as postmortal accumulations in this study. Key words:...
195

Skeletal changes after post-mortem exposure to fire as an indicator of decomposition stage

Keough, Natalie January 2013 (has links)
Forensic anthropologists and taphonomists are often tasked with interpreting the sequence of events from death through decomposition to skeletonisation. Discovery of burnt bone often evokes questions as to the condition of the body prior to the burn event. The purpose of this study was to evaluate features of thermal damage on bones in relationship to the condition of the bone (dry/wet) and progression of decomposition. Twenty-five pigs in various stages of decomposition (fresh, early, advanced, early & late skeletonisation) were exposed to fire for 30 minutes. The skeletal elements were scored and features included: colour change (unaltered, charred, calcined), brown and heat borders, heat lines, delineation, greasy bone, joint shielding, predictable and minimal cracking, delamination and heatinduced fractures. Colour changes were scored according to a ranked percentage scale (0 – 3) and the remaining traits as absent or present (0/1). Cohen’s Kappa statistics evaluated intraand interobserver error. Density plots and frequency distributions were constructed and multiple regression (categorical variables) and transition analysis were employed. The majority (8) of the 13 traits displayed potential to predict decomposition stage from burned remains. An increase in calcined and charred bone occurred synchronously with an advancement in decomposition. The organic composition of bone and presence of flesh affect the characteristics features of burned bone. Greasy bone occurred most often in the early/fresh stages (fleshed bone). Heat borders, heat lines, delineation, joint shielding, predictable and minimal cracking were associated with wet tissue/bone; whereas brown burn/borders, delamination and other heat-induced fractures were associated with early and late skeletonisation. No statistically significant differences were noted among observers for the majority of the traits except for predictable and minimal cracking and heat-induced fractures in the cranium. Heat-induced changes may assist in estimating decomposition stage from unknown, burnt remains and thereby aid in a providing an indication as to the condition of the bone prior to the burn event. / Thesis (PhD)--University of Pretoria, 2013. / gm2014 / Anatomy / unrestricted
196

Změny vnějších povrchů koster dolních končetin způsobené tafonomickými faktory: Pohansko, 2. kostel / Changes in the external surfaces on the lower limb bones caused by taphonomic factors: Pohansko, 2nd church

Vitnerová, Tereza January 2020 (has links)
Changes in the external surfaces on the lower limb bones can be caused by various taphonomic factors. It is important for our work how these changes will affects. The aim of the work was to process and subsequently evaluate the changes in the external surfaces on the lower limb bones. For analyses we chose set of adults from 2nd church burial ground Pohansko near Břeclav, we chose specifically braid of the lower limbs (cingulum membri inferioris) and free lower limb (pars libera membri inferioris). We wrote down taphonomic changes into prepared protocols, changes were typologically about damages and color changes. We used programs InkScape and AdobePhotoshop to transform paper protocols into digital form. Heat maps are outputs from this programms through them we are able to see incidence rate of individual changes. We most often detected the occurrence of an orange color on the bones of the lower limbs, so we focused on its cause. We found an increased content of silicon and aluminum in its chemical composition, so we assume that it could be an aluminosilicate weathering product. Key words: Pohansko, taphonomy, taphonomic factors, bone surface, lower limb
197

A histological examination of bone weathering

Liggett, Isabella A. 10 March 2022 (has links)
This project histologically examined weathering on faunal bones. The sample consisted of a mixture of faunal remains, assessed and assigned to weathering stages (WS) 0-2 from Behrensmeyer’s (1978) scoring method. A total of 77 bones sections were observed for histological analysis. A portion were obtained, partially fleshed, commercially and were placed at the Outdoor Research Facility (ORF) in Holliston, MA. After deposition, bones were collected at specific time intervals allowing for 2, 4, 6, 8, 12, and 18-month exposure times. Bones were also collected from several outdoor locations in Ohio, having been exposed for an unknown period, and ranging from WS 0-2. Following histological preparation of the sample, the microstructure of each weathering stage was observed using the image analysis software Fiji from the National Institutes of Health (NIH). Data recorded included the number of cracks present per unit area and the depth of cracking. The number of cracks per unit area for each section of bone was calculated by dividing the number of cracks per section by the total section area resulting in number of cracks per mm2. Depth of cracking was analyzed through maximum crack length and average crack length. This data was compiled and one-way ANOVA tests were applied to determine where weathering stage and exposure time were statistically significant. This was followed by Bonferroni post-hoc analyses which were utilized to analyze the interactions within the WS and exposure time variables; to allow for analysis of statistical significance of WS to one another and exposure time intervals to one another. It was hypothesized that different weathering states would be statistically significant from one another, and microscopically identifiable through a histological examination, and that these would be able to be differentiated from other sources of microtaphonomic alteration including burial and thermal alteration. It was also hypothesized that exposure time would significantly impact the histological characteristics including the number of cracks per mm2 and the maximum and average crack depth. One-way ANOVA analysis indicated that WS has a significant impact on the number of cracks per mm2 and the maximum crack length. No significance was observed for analysis of WS and average crack length. Post-hoc analysis involving the number of cracks per mm2 revealed statistical significance between WS 0 and WS 1, WS 0 and WS 2. Analysis involving maximum crack length indicated significance only between WS 0 and WS 1. Post-hoc analysis involving average crack length did not indicate any statistically significant relationships between the WS. One-way ANOVA analysis of exposure time indicated that exposure time has a significant impact when on all three variables: number of cracks per mm2, average crack length, and maximum crack length. Post-hoc analysis involving the number of cracks per mm2 found that months 0, 2, 4, 6, and 8 were all statistically significant from 18 months. Analysis of average crack length revealed that months 0 and 2 were both statistically from 8 months of exposure. Post-hoc analysis involving maximum crack length reveals statistical significance between months 0 and 8, 0 and 12, and 2 and 8. Histological characteristics of weathered bone were found to include delamination and cracking. Delamination was observed on several bones in WS 2 and one in WS 1, while cracking was observed in bones of all stages. Positive relationships were observed between WS and number of cracks per mm2, and between exposure time and cracks per mm2 indicating that as one increased so did the other. No trend was observed for the relationship between exposure time and either of the crack length variables; the same was observed for the relationship between WS and the two crack length variables. Through comparison of the histological characteristics of weathered bone with other sources of microtaphonomic alterations, it was determined that weathering and its histological characteristics are different from other alteration sources, including burial and thermal alteration, to allow for determination of the microtaphonomic process affecting the bone.
198

Structural Bone Density of Pacific Cod (<i>Gadus macrocephalus</i>) and Halibut (<i>Hippoglossus stenolepis</i>): Taphonomic and Archaeological Implications

Smith, Ross E. 01 January 2008 (has links)
Describing prehistoric human subsistence strategies and mobility patterns using archaeofaunal assemblages requires archaeologists to differentiate the effects of human behavior from natural taphonomic processes. Previous studies demonstrate that differences in bone density both within and between taxa contribute to variation in element representation in archaeofaunal assemblages. Measurements of contemporary Pacific Cod (Gadus macrocephalus) and Pacific Halibut (Hippoglossus stenolepis) skeletal elements using Dual Energy Absorptiometry (DEXA) and hydrostatic weighing revealed differences in bone volume density between elements and taxa. Density values were highest in Pacific cod and halibut jaw elements; the lowest bone volume densities were measured in Pacific cod and halibut basipterygia. While halibut and salmon often exhibited similar bone density values, the densities of Pacific cod elements were consistently higher than those from either salmon or halibut. These density data indicate that the remains of Pacific cod are more likely to persist in archaeological deposits. When combined with existing salmon bone density measurements, these data allow for the identification of density-mediated destruction in fish faunal assemblages from along the North Pacific rim. Analysis of cod, halibut and salmon faunal assemblages from the North Point, Cape Addington Rockshelter, Rice Ridge, Uyak and Amaknak Bridge sites revealed that density-mediated element attrition has not consistently affected cod, halibut and salmon element representation in these sites. Significant correlations identified in aggregate site assemblages were not present at finer scales of analysis; the effects of density-mediated element attrition varied between depositional contexts. This research demonstrates that bone density data can be used to differentiate the effects of density-mediated element attrition from the results of human decision-making. Once density-mediated element attrition is ruled out, archaeologists can examine the effects of human processing, transportation, preparation and disposal activities on the distribution of Pacific cod and halibut skeletal elements both within and between archaeological contexts.
199

Cave usage and the implications of multiple taphonomic agents on a faunal assemblage

Bountalis, Alexandra Clare 01 February 2013 (has links)
The means in which fossil accumulations in the caves of southern Africa have formed is of great importance. One method of accumulation is via the collecting behaviours of a variety of mammalian species. The core of said behaviour is in the use of caves by these species. This project was designed to give insight to the way that animals in the Cradle of Humankind, South Africa are using caves today. The objective of this research is to give a new understanding to the amount that caves are used by various taxa in South African cave systems, with particular regard to taphonomic agents and potential taphonomic agents. This study was accomplished over a 20-month period by setting up motion sensor cameras outside of cave entrances at the Malapa Nature Reserve. Results have shown that animals use caves at high frequencies, crucial to recognize when examining fossil accumulations.
200

Mass Spectrometry-Based Identification of Ceramic-Bound Archaeological Protein Residues: Method Validation, Residue Taphonomy, and Prospects

Barker, Andrew Lewis 12 1900 (has links)
Despite the variety of successful reports of the preservation, recovery, and identification of archaeological proteins in general, there are few positive reports regarding mass spectrometry-based identification of ceramic-bound proteins. In large part, this shortage is due to the lack of consideration for the unique taphonomic histories of such residues and, in general, methods development. Further, because negative results are rarely published, there is no baseline to which results can be compared. This paper attempts to address these challenges via a multi-pronged approach that uses mass spectrometry and complementary approaches to evaluate ceramic-bound protein preservation in both controlled, actualistic experiments, and in archaeological artifacts. By comparing the results obtained from protein-spiked, experimentally-aged ceramic to those obtained from both faunal and ceramic archaeological materials, an enhanced perspective on protein preservation and subsequent recovery and identification is revealed. This perspective, focusing on taphonomy, reveals why negative results may be the norm for ceramic artifacts when non-targeted methods are employed, and provides insight into how further method development may improve the likelihood of obtaining positive results.

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