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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

Standing Stocks and Faunal Zonation of Deep-Sea Benthos: Patterns and Predictions across Scales

Wei, Chih-Lin 2011 May 1900 (has links)
The deep ocean (> 200-m depth) covers more than 65 percent of earth's surface and is known as the largest active carbon sink of the planet. Photosynthesis fixes inorganic carbon into organic rich-compounds to fuel the biological production in the upper ocean. A small portion of the photosynthetic carbon eventually sinks to the seafloor to support diverse deep-sea life. In this dissertation, the phytoplankton production and export flux of particulate organic carbon (POC) to the seafloor were linked to standing stocks and compositional changes of the deep-sea soft bottom assemblages. The pattern and processes of energy transfer from the surface ocean to the deep sea was examined by modeling the global benthic bacteria, meiofauna, macrofauna, and megafauna biomass from remotely sensed ocean color images and the seafloor relief. The analysis was then scaled down to the macrofauna of the Gulf of Mexico (GoM) to examine the global pattern on regional oceanic features with contrasting productivity regimes. These results suggested a universal decline of benthic standing stocks down the continental margins that is caused by an exponential decrease of export POC flux with depth. A revisit of historical epibenthic invertebrate sampling in the North Atlantic showed that both individual species and multi-species assemblages occurred in narrow depth bands that hugged the topography from the upper continental slope out to the Hatteras Abyssal Plain. The continuum compositional change suggested that the continuous decline of benthic food supply with depth was the potential driving force for the pattern of bathymetric faunal zonation. A broad, systematic survey across multiple depth transects in the northern GoM suggested that macrofauna zonation is not only taking place across isobaths, but also form the northeast to the northwest GoM due to a horizontal productivity gradient created by the nutrient-laden Mississippi River. Analyses of long-term demersal fish data from 1964 to 2002 in the northern GoM showed no evidence of large-scale faunal change across different sampling times. Base on the pooled data, a shift in rate of fish species replacement may be caused by complex biological interactions or changes in environmental heterogeneity along depth or productivity gradients.
52

Eating inequality : food, animals and people at Bosutswe

Atwood, Kirsten Marie 02 July 2014 (has links)
This study addresses the use of wild and domestic animals at the Iron Age site of Bosutswe, Botswana. I argue that that the Western (commoner) inhabitants consumed more wild game than Central (elite) inhabitants. The overall roll that wild animals played in the diet decreased radically over time, perhaps due to environmental degradation, a change in hunting practices, or due to a combination of both factors. The importance of domestic animals increased over time. Both commoners and elites had access to cattle and small stock, but elites consumed a greater amount of these species. During the Early and Middle Lose, Bosutswe elites were able to preferentially consume young and aged domestic animals rather than consuming mainly adult animals. This may have been a form of conspicuous consumption. Despite the differences in what was eaten, how meat was cooked appears to be similar amongst both commoners and elites. Meat appears to have largely been boiled, as much meat is in Botswana today. The elite inhabitants of Bosutswe retained much of the favored cuts of meat- upper limbs- for themselves. Less-favored cuts of meat, especially lower limbs and craniums, were distributed to the commoners of Bosutswe. This redistribution of resources may have provided the commoners of Bosutswe with tangible material benefits, but also served to emphasize their non-elite status and reinforce the social hierarchy. Likewise, herding cattle may have provided commoners with access to their labor and milk, but also served to codify and increase social hierarchy by enabling elites to maintain large cattle herds. / text
53

Análise quantitativa, sobreposição de nicho e coocorrência de moscas-das-frutas (Diptera: Tephritidae) em três pomares adjacentes / Quantitative analysis, niche overlap and co-occurrence of fruit flies (Diptera: Tephritidae) on three adjacent orchards

Gleidyane Novais Lopes Mielezrski 26 May 2014 (has links)
Este trabalho teve por objetivo o conhecimento dos padrões sazonais de abundância e o potencial para associações positivas e negativas entre espécies do gênero Anastrepha e Ceratitis capitata. As coletas foram realizadas na estação experimental do Polo Regional de Desenvolvimento Tecnológico dos Agronegócios do Leste Paulista/Agência Paulista de Tecnologia dos Agronegócios (PRDTALP/APTA), em Monte Alegre do Sul, SP, Brasil. As moscas-das-frutas foram coletadas em armadilhas tipo McPhail contendo torula, em pomares de goiaba (Psidium guajava), nêspera (Eriobotrya japonica) e pêssego (Prunus persica), de janeiro de 2002 a janeiro de 2004. Em cada pomar, foram instaladas três armadilhas, cujo atrativo alimentar era substituído semanalmente. Os espécimes de Anastrepha e C. capitata foram sexados, contados, etiquetados e fixados em etanol 70%. A identificação específica de Anastrepha foi feita, exclusivamente, nos caracteres morfológicos das fêmeas. As comunidades de moscas-das-frutas foram caracterizadas por parâmetros faunísticos (dominância, abundância, frequência e constância), índices de diversidade (H\'), riqueza e equitabilidade (E). A influência dos pomares na flutuação populacional das espécies predominantes foi avaliada pelos índices fisiográficos. Com base em modelos nulos, foram estudadas, pela primeira vez no Brasil, a sobreposição de nicho e a coocorrência de populações de mocas-das-frutas. Em 106 coletas, nos três pomares, foram obtidos 25.872 espécimes de Ceratitis capitata (21.252 fêmeas e 4.620 machos) e 89.958 do gênero Anastrepha (48.042 fêmeas e 41.916 machos). Treze espécies de Anastrepha foram capturadas no pomar de goiaba, 19 no de nêspera e seis no de pêssego, além de C. capitata. As espécies predominantes, portanto, classificadas como super nos quatro parâmetros quantitativos, foram A. fraterculus (Wiedemann), A. sororcula Zucchi, A. bistrigata Bezzi, A. obliqua (Macquart) e C. capitata (Wiedemann). Houve diferença significativa quanto ao índice fisiográfico e umidade relativa apenas para A. bistrigata e C. capitata no pomar de goiaba e para A. fraterculus, A. bistrigata e C. capitata, no pomar de nêspera. No pomar de pêssego, não houve diferença significativa para as espécies estudadas. Anastrepha fraterculus foi a espécie mais representativa nos pomares de goiaba e de nêspera e C. capitata, no pomar de pêssego. As características da comunidade (diversidade, riqueza e equitabilidade) sofreram alterações de ano para ano. Além dos fatores climáticos e da disponibilidade hospedeira, a competição interespecífica também interferiu na dinâmica populacional de moscas-das-frutas. Ceratitis capitata e A. pseudoparallela ocorreram com pouca ou nenhuma frequência, respectivamente, com as espécies de Anastrepha nos pomares de goiaba e nêspera. No entanto, no pomar de pêssego, C. capitata ocorreu em agregações significativas com algumas espécies de Anastrepha. Anastrepha fraterculus não foi fortemente influenciada por fatores interespecíficos na estação experimental em Monte Alegre do Sul, SP, Brasil. / The main objective of this study was to know the seasonal patterns of abundance and the potential for positive and negative associations among fruit fly species belong to Anastrepha and Ceratitis capitata. The collecting sites were at experimental station of the Polo Regional de Desenvolvimento Tecnológico dos Agronegócios do Leste Paulista/Agência Paulista de Tecnologia dos Agronegócios (PRDTALP/APTA), in Monte Alegre do Sul, SP, Brazil. Fruit flies were collected in McPhail-type traps baited with torula hung in trees of guava (Psidium guajava), loquat (Eriobotrya japonica) and peach (Prunus persica), from January 2002 to January 2004. Three traps were distributed in each orchard, and the bait was replaced weekly. Specimens of Anastrepha and C. capitata were sexed, quantified, labeled, and conserved in 70% ethanol. The identification of Anastrepha species was based exclusively on females. Communities of fruit flies were characterized by faunal indices such as dominance, abundance, frequency and constancy, diversity (H\'), richness and evenness (E). The influence of orchards on the population dynamics of the dominant fruit fly species was estimated by physiographic indices. Based on null models, the niche overlap and co-occurrence of population of fruit flies were studied, for the first time in Brazil. From 106 collections, were obtained 25,872 specimens of Ceratitis capitata (21,252 females and 4,620 males) and 89,958 of the genus Anastrepha (48,042 females and 41,916 males). Thirteen species of Anastrepha were collected in guava, 19 in loquat, and 6 in peach orchard. The predominant species, classified as a super on the four quantitative parameters, were A. fraterculus (Wiedemann), A. sororcula Zucchi, A. bistrigata Bezzi, A. obliqua (Macquart) and C. capitata (Wiedemann). There were significant differences in the physiographic index and humidity only to A. bistrigata and C. capitata in guava orchard and A. fraterculus, A. bistrigata and C. capitata in loquat orchard. In the peach orchard, there was no significant difference for the species studied. Anastrepha fraterculus was the most significant species in the orchards of guava and loquat, and C. capitata was the most significant species in peach orchard. The community characteristics (diversity, richness and evenness) changed from year to year. Further on climatic factors and host availability, interspecific competition also interfered with the population dynamics of fruit flies. Ceratitis capitata and A. pseudoparallela showed little or no frequency, respectively, together other Anastrepha species in guava and loquat orchards. However, in the peach orchard, C. capitata occurred in significant aggregations with some species of Anastrepha. Anastrepha fraterculus was not strongly influenced by interspecific factors at the experimental station in Monte Alegre do Sul, SP, Brazil.
54

Characterization of hydrothermal vent faunal assemblages in the Mariana Back-Arc Spreading Centre

Giguere, Thomas 04 May 2020 (has links)
Researchers have learned much about the biological assemblages that form around hydrothermal vents. However, identities of species in these assemblages and their basic ecological features are often lacking. In 2015, the first leg of the Hydrothermal Hunt expedition identified likely new vent sites in the Mariana Back-arc Spreading Center (BASC). In 2016, the second leg of the expedition used a remotely operated vehicle (ROV) to confirm and sample two new sites and two previously known sites. My first objective is to identify the animals collected from these four vent sites. In these samples, I identify 42 animal taxa, including the discovery of four new vent-associated species, five potentially new species and six taxa not previously reported in the Mariana BASC vents. My second objective is to combine these new data with previous studies and examine the species distributions among all known vent sites in the Mariana BASC using the α-, β-, and γ-diversity framework. I present updated species absence-presence lists for all eight Mariana BASC vent sites, which begin to resolve some of the issues with species identification. In this thesis, my approach to assessing β-diversity is novel in the field of hydrothermal vent ecology. My work also provides the first intra-regional scale assessments of β-diversity that include all sites known in a vent system. My third objective is to explore environmental factors driving these species distribution patterns. The α-diversity of BASC vent sites gradually increases with latitude, and the β-diversity calculated using the Raup-Crick index correlates with distance to nearby vent sites. Stochastic assembly processes likely shape the diversity patterns throughout the Mariana BASC as few environmental variables are known to correlate with these patterns. My fourth objective is to compare the β-diversity patterns between the Mariana BASC vent sites and those in two other vent systems: the Mariana Arc and the Juan de Fuca Ridge. The γ- and average α-diversity values for the BASC vents are relatively low compared to the other two systems. The Jaccard index revealed that the average number of shared species among the Arc vent sites is much lower than those of the BASC and the Juan de Fuca Ridge. The Raup-Crick index indicates that stochastic processes explain the average β-diversity of the Mariana BASC vents better than those of the Mariana Arc and Juan de Fuca Ridge. / Graduate / 2021-04-17
55

Were they or weren't they? A study of possible sedentariness using faunal indicators at a coastal Thom's Creek site (38ch1693)

Alford, Lauren Lowrey 06 August 2011 (has links) (PDF)
Site 38CH1693 is a coastal site located in Charleston County, South Carolina. Thom’s Creek ceramics place the site in the Late Archaic/Early Woodland Period and radiocarbon dating corroborates this, placing the features present between 3650 and 3950 BP. Faunal analysis was undertaken to assess seasonality in order to understand the occupations that occurred at the site. Faunal seasonality, botanical seasonality, and sedentariness indicators are used to determine the sedentariness of the site. The presence of certain marine fish species is one of the most important seasonality indicators used. It is determined from the available evidence that at least one short-duration, year-round occupation is represented by the materials recovered at 38CH1693. Site 38CH1693 does not fit into the current Late Archaic settlement pattern models for the coast, calling for a reevaluation of these settlement pattern models and the sedentary sites within them.
56

Ritual and Funerary Rites in Later Prehistoric Scotland: An Analysis of Faunal Assemblages from the Covesea Caves

Fitzpatrick, Alexandra L. January 2020 (has links)
The Covesea Caves are a series of later prehistoric sites that form a complex mortuary landscape. Previous excavations of the caves have provided evidence for the decapitation, disarticulation, and intentional deposition of human remains. Although there has been substantial analysis of the human remains, there has been little consideration of the significant number of faunal remains recovered during numerous excavations. This research represents the first focused examination of the extensive zooarchaeological record from the Covesea Caves, with an emphasis on investigating characteristics of the faunal bone related to taphonomy and processing in order to provide a proxy for the complex funerary treatments to which the human remains were subject. Analysis of Covesea Cave 2 revealed a narrative of ritual and funerary activities, from the Neolithic to the Post-Medieval Period. Zooarchaeological analysis has illustrated how certain species were significant in ritual activity, and thus utilised specifically in funerary rites. The results from this research shed more light on past cosmologies and the importance of non-human species to humans in both life and death. / Funding for fieldwork was provided by Historic Environment Scotland and Aberdeenshire Council. Lab work and species confirmation was funded by a generous grant from the British Cave Research Association. Funding for this [comparative] analysis was provided by the following organisations: The Prehistoric Society, The Society of Antiquaries of Scotland, The Natural History Society of Glasgow
57

Subsistence at Si•čǝ’nǝł: the Willows Beach site and the culture history of southeastern Vancouver Island

Willerton, Ila Moana 03 September 2009 (has links)
Culture types in Pacific Northwest archaeology are characteristic artifact assemblages distinguishing different prehistoric periods. Assemblages indicate a culture type transition during the 2,630 BP–270 BP occupation of Willows Beach (DcRt-10), southeastern Vancouver Island. Faunal remains could reveal links to subsistence patterns, following Croes’s theory that culture type change reflects subsistence intensification. Five dated DcRt-10 faunal assemblages underwent taxonomic and size classification, weighing and MNI calculation. Vertebrate weight and NISP percentages were compared between stratigraphic units associated with the later Gulf of Georgia and earlier Locarno Beach culture types. The youngest assemblage contains a smaller proportion of land mammal bone, suggesting increased sea mammal, fish, and bird procurement. Faunal remains also suggest a greater variety of taxa exploited over time. Faunal assemblages suggest that culture type change at DcRt-10 is the product of subsistence change, increasing knowledge of the culture historic sequence of this region.
58

Taken to the grave : an archaeozoological approach assessing the role of animals as crematory offerings in first millennium AD Britain

Worley, Fay L. January 2008 (has links)
The crematory funerary rites practiced by those living in parts of mainland Britain during the first millennium AD included burning complete or parts of animals on the pyre. This thesis highlights the potential for archaeozoological analysis of faunal pyre goods using assemblages from the first millennium AD as a dataset. Experimental study and the integration of current research from a number of disciplines is used to suggest that although pyrolysis and cremation practices fragment and distort burnt bone assemblages, careful analysis can reveal a wealth of data leading to the interpretation of various forms of pyre good. The results of the author's analysis of material from the sites of Brougham, Cumbria, St. Stephen's, Hertfordshire, Castleford, West Yorkshire and Heath Wood, Derbyshire are combined with data from other published cemeteries to suggest a series of chronological and regional continuities in the use of animals but with a distinct change at the start of the Early Medieval period. The results from Brougham are particularly significant as they alter preconceived views on the utilisation of animals in Romano-British funerary practice. Cremation burials in first millennium AD Britain are shown to include the burnt remains of predominantly domestic taxa with occasional wild species. The pyre goods are interpreted as representing food offerings, companions, amulets, gaming items and sacrifices. This thesis demonstrates that cremated animal bone should not be disregarded but rather valued as source of archaeozoological data, and a significant functional tool for interpreting past funerary behaviour and animal utilisation.
59

Fylogeneze a biogeografie neotropických a afrických říčních cichlid: využití multilokusových metod ke studiu evoluce / Phylogeny and biogeography of Neotropical and African riverine cichlids: multilocus phylogenetic methods in the evolutionary studies

Musilová, Zuzana January 2011 (has links)
Summary: The thesis comprises from the introduction and five main parts: three of them are published papers, the rest two are manuscripts prepared for submitting to the scientific journals. The first two are published phylogenetic studies of the cichlasomatine cichlids based on (1) molecular characters, and (2) both morphological and molecular data with the description of a new genus Andinoacara. The third (3) is the already published description of the new species Andinoacara stalsbergi from Peru combining both morphological and phylogenetic approaches and including the detailed phylogeny of the genus Andinoacara. The next unpublished manuscript (4) is the more detailed comprehensive phylogeography of the two non-relative genera (including Andinoacaras) of the trans-Andean cichlids. Including all valid species from the majority of their distribution areas it was reconstructed the ancestral area of both genera in the Choco region, Colombia, and revealed the directions of their distribution spreading. The last (5) unpublished manuscript is the phylogeographical study of the cichlid genus Serranochromis from the headwaters of the totally unknown Central Angola. It showed several evidences of the faunal exchange among the adjacent river systems. Lastly, the thesis is supplemented by several appendices...
60

L’exploitation faunique au site BiFk-5 : étude zooarchéologique des restes squelettiques mammaliens

Laperrière-Désorcy, Louis-Vincent 12 1900 (has links)
No description available.

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