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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.

Cambrian arthropods from North Greenland and their evolutionary significance

Budd, Graham Edward January 1994 (has links)
No description available.

A review of heavy metal levels in marine invertebrates and some studies of mercury in seabirds

Thompson, David Richard January 1989 (has links)
No description available.

Piura: La isla Foca alberga una fauna incomparable

Keusche Sarmiento, Kirby Fernando Vicente 03 March 2013 (has links)
Entrevista al Prof. Keusche Sarmiento, Kirby Fernando Vicente sobre la isla Foca, fauna única en el mundo.

The bivalves of the Spilsby Sandstone Formation and contiguous deposits

Kelly, Simon Richard Appleton January 1977 (has links)
Hitherto the bivalve fauna of the Spilsby Sandstone and contiguous deposits including the lower part of the Sandringham Sands and Speeton Clay of-Middle Volgian to Ryazanian age has been inadequately described. As a consequence of this study 92 taxa have been recorded. 45 of these are described fully and include 13 new species and one new subgenus. Information has been obtained from the author's collecting and from museum' collections. Locality and section information is given for sites examined by the author. The preservation of the fauna is normally as moulds, but cold cure silicone rubber has been used to obtain casts with great success. The ecology of the less well understood bivalves is discussed. Five bivalve dominated assemblages are recognised. They represent various shallow marine facies. The sediments include glauconitic sands and silts with condensed sequences containing phosphatised nodules and also a sideritic ironstone occurs. A facies model is produced for the East Midlands Shelf, and the contemporary relationships with other parts of England are discussed. The Spilsby basin represents a westerly embayment or estuary of the Southern North Sea basin. In Middle Volgian times there were marine connections to the Wessex basin to the south, but with the subsequent draining of this latter area in Upper Volgian to Ryazanian times to restricted marine, brackish and freshwater lagoonal environments, open marine connection ceased. The Spilsby basin remained fully marine during these times, but became more enclosed. The Spilsby bivalve fauna indicates strong faunal similarities with Boreal regions, and in particular with East Greenland and the Russian Platform. The fauna also compares closely with the sandy Upper Kimmeridgian facies in central England but contrasts strongly with the contemporary faunas of the Portland and Purbeck Beds. The relationships of the Spilsby fauna with other Boreal regions and with Tethyan Europe are discussed.

Análise da comunidade bacteriana de animais marinhos recolhidos do litoral norte do Rio Grande do Sul / Analysis of the bacterial community from marine animals found in the coastal north Rio Grande do Sul

Medeiros, Aline Weber January 2016 (has links)
O conhecimento sobre a microbiota de animais marinhos fornece uma base que pode ser usada para comparação em virtude de mudanças futuras, apesar disso pouco se sabe sobre a natureza das bactérias associadas com o intestino desses animais. Esse estudo visou a obtenção de um panorama sobre a microbiota de animais marinhos selvagens recolhidos no litoral do Rio Grande do Sul através de ferramentas independentes de cultivo, como o sequenciamento de última geração e PCR quantitativa em tempo real (qPCR), que permitem a inferência sobre as bactérias pertencentes a microbiota intestinal a partir do DNA genômico total obtido diretamente da amostra. A partir do sequenciamento parcial do gene de 16S rRNA utilizando a plataforma de alta desempenho Ion Torrent PGM, seis amostras fecais de lobo-marinho-sul-americano (Arctocephalus australis) e quatro lobo-marinho- subantártico (Arctocephalus tropicalis) foram avaliadas. Verificou-se que o filo Firmicutes (86,28%) foi mais frequente nas fezes de ambas as espécies, seguido por Actinobacteria(6,74%) e Proteobacteria (3,34%), sendo Bacteroidetes e Fusobacteria os filos menos frequente. A qPCR foi empregada para quantificar as espécies de enterococos, mais frequentemente isoladas de fezes de animais (Enterocococcus faecalis, E. hirae, E. mundtti, E. faecium, E. gallinarum e E. casseliflavus), em amostras fecais de animais marinhos selvagens. A partir de DNAs totais isolados de 24 amostras fecais de lobos marinhos, tartarugas-verdes e aves marinhas, verificou-se que E. faecalis (1,82x1012 cópias/ng) foi a espécie mais frequente em todas as amostras analisadas e E. hirae (5,89x1010), E. mundtti (7,57x1010 cópias/ng), E. faecium (4,94x1009 cópias/ng), E. casseliflavus (1,22x1009 cópias/ng) e E. gallinarum (3,84x1010 cópias/ng) também demonstraram estar presentes na microbiota desses animais. / Knowledge about the marine animals microbiota provides a base that can be used for comparison due to future changes, nevertheless little is known about the nature of the bacteria associated with the animal gut. This study aimed to obtain an overview of the microbiota of wild marine animals collected in the Rio Grande do Sul coast using cultive independent methods, as the next-generation sequencing and quantitative real-time PCR ( qPCR ), which allow the inference about the bacteria belonging to the intestinal microbiota from total genomic DNA obtained directly from the sample. Using the high performance Ion Torrent PGM platform six fecal samples of South American fur seal (Arctocephalus australis) and four Subantartic fur seals (Arctocephalus tropicalis) were evaluated. It was found that the phylum Firmicutes (86.28%) was more common in faeces of both species, followed by Actinobacteria (6.74%) and Proteobacteria (3.34%), Fusobacteria and Bacteroidetes were the least frequent. The qPCR was used to quantify the Enterococci species commonly isolated from faecal samples of animal (Enterocococcus faecalis, E. hirae, E. mundtti, E. faecium, E. gallinarum e E. casseliflavus) in faecal samples or cloacal swabs / rectal wild marine animals. From total DNA isolated of 24 fecal samples from sea lions, green turtles , sea birds, it was observed that E. faecalis (1.82x1012 copy/ng) was the most common species in all samples analyzed and E. hirae (5.89x1010), E. mundtti (7.57x1010), E. faecium (4.94x1009), E. casseliflavus (1.22x1009) and E. gallinarum (3.84x1010) also shown to be present in the microflora of these animals.

The fish fauna of Lobster Bay, Cape D'Aguilar, Hong Kong

Leung, Wai-yin, Albert., 梁懷彥. January 1994 (has links)
published_or_final_version / Ecology and Biodiversity / Master / Master of Philosophy

Community ecology and genetics of macroinvertebrates in permanent Macaronesian streams

Kelly, Lucy Claire January 2001 (has links)
Extensive community-based sampling and single-species genetic analysis were used to study factors driving stream invertebrate community assembly on islands. Macroinvertebrates and physicochemistry were surveyed in forty-two streams on La Palma, La Gomera, Tenerife and Madeira (Macaronesia). Island faunal relationships and the role of the stream and catchment environment in determining community composition were investigated with multivariate analyses; assemblage nestedness and species richness, occupancy and abundance were also examined. The relationship between genetic differentiation and range size was tested using allozyme variation in selected species. Island species pools differed in community composition and species richness (total, and endemic), broadly as predicted by theory of island biogeography. Stream and island species richness were correlated, showing unsaturated, possibly dispersal-limited, communities, and stream faunas were nested, evidence that assemblages were not random (e.g. only generalist/dispersive taxa occur at species-poor sites). Endemics occurred in more streams than non-endemics, suggesting greater habitat availability for the former, but similar niche width, endemic and non-endemics having similar local abundance. Species richness, community composition and the abundances of individual species were correlated with stream physicochemistry, itself reflecting geology, rainfall, altitudinal zonation of vegetation and the intensity of stream exploitation. Allozyme variation was surveyed in Mesophylax aspersus (Trichoptera: Limnephilidae) and Wormaldia tagananana (Trichoptera: Philopotamidae), respectively having widespread and localised distributions. Population structure supported the hypothesis that range size is, at least partly, limited by poor dispersal ability in W tagananana. Genetic variation in Ancylus striatus (Gastropoda: Ancylidae) was typical of polyploidy and selffertilisation/ parthenogenesis. Breeding system has consequences for a species' colonisation ability, and may partially explain the wide distribution of A. striatus within the islands. Variation in community composition reflected patterns at a range of scales. Biogeography detennined the island species pooL whilst local physicochemistry determined richness and community composition within islands. Species characteristics that affect their colonisation and c:\tinction probabilities (e.g. habitat selection at the local- and mesoscaks, dispersal patterns and breeding system). influence hoth the local and regional species pools.

Some aspects of faunal distribution in the intertidal meiobenthos

Johnston, N. A. January 1981 (has links)
No description available.

Silurian-Middle Devonian Acanthodian Faunas of Eastern Australia

Burrow, C. J. Unknown Date (has links)
No description available.

An Investigation into the Landscape Ecology and Dynamics of Vegetation Remnants on the Rural Residential Fringe of Brisbane, Australia.

Melville, S. Unknown Date (has links)
No description available.

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