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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.
81

SPECIATION ALONG THE PERUVIAN ANDES-AMAZON TRANSITION ZONE: PHYLOGEOGRAPHY AND LANDSCAPE GENETICS OF THE AMEEREGA PETERSI GROUP (FAMILY: DENDROBATIDAE)

French, Connor Martin 01 August 2018 (has links)
The Amazon rainforest along the Andean foothills contains exceptionally high diversity, much of it recent. The complex geology of the Andes and paleoclimate fluctuations preclude complex dispersal scenarios. This, in turn, has contributed to idiosyncratic speciation modes among shallowly-diverged Amazonian taxa. The poison frog genus Ameerega recently radiated throughout the Andes and Amazon (MRCA ~8.7 mya), with some taxa diverging as recently as the late Pliocene and early Pleistocene. Some species-level relationships remain poorly resolved, especially among recently diverged taxa. Here, I define ancestral populations and address the phylogenetic relationships among three recently diverged Peruvian Ameerega species (A. cainarachi, A. petersi, and A. smaragdina), using multiple species tree methods, including one that accounts for reticulate evolution. I complement species tree inference with assessments of behavioral divergence and niche overlap to better resolve species boundaries. I further explore the phylogeographic history of these species of Ameerega with demographic inference, considering evidence for population expansions. These analyses provide the basis to address speciation hypotheses in the Andean lowlands, including the refugial hypothesis and dispersal-vicariance hypothesis. I find support to synonymize A. smaragdina with A. petersi, and that divergent and convergent reticulation processes and historical range expansion impacted the A. petersi group’s speciation history. In addition, I use species distribution modeling (SDM) to infer the A. petersi group’s range dynamics since the mid-Pleistocene (785 kya). SDMs reveal periods of range expansion, contraction, and shifts, tracking climate fluctuations during the Pleistocene. In order to explicitly consider the relative roles of climate and geography in structuring genetic diversity at different time periods, I use a landscape genetics approach and consider 21 isolation-by-resistance hypotheses. These hypotheses include climatic resistance layers from five time periods in the Pleistocene, a stability layer, two geographic layers that reflect the two species’ natural history (distance-from-river and mid-elevation resistance), and composite layers that pair geographic and environmental layers. I find that climate stability and river proximity best explain gene flow. I find that phylogeographic, niche modeling, and landscape genetic evidence supports a dispersal-vicariance model of speciation in the A. petersi group.
82

A Biogeografia no núcleo de Rio Claro (SP): análise e avaliação das contribuições científicas no período de 1969-2004

Galina, Márcia Helena [UNESP] 05 October 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-10-05Bitstream added on 2014-06-13T18:42:00Z : No. of bitstreams: 1 galina_mh_dr_rcla.pdf: 5978263 bytes, checksum: d9a923866cbb7605e929327bfe026257 (MD5) / Os objetivos da presente pesquisa compreenderam o resgate, o levantamento, a análise e a avaliação sistemática das contribuições e originalidades geradas pela produção científica na área de Biogeografia, desenvolvida no período de 1969 a 2004, por professores, pesquisadores e alunos do Departamento de Geografia e de Pós-Graduação em Geografia, Instituto de Geociências e Ciências Exatas de Rio Claro, da Universidade Estadual Paulista, mais diretamente envolvidos com a temática biogeográfica. A partir do levantamento anterior houve a classificação das pesquisas dentro das áreas específicas da Biogeografia, a fim de identificar as subáreas mais contempladas e as que vêm apresentando maior desenvolvimento. Também houve alusão às abordagens espaciais e às escalas mais comumente utilizadas nessas pesquisas. A divulgação do papel de destaque dos pesquisadores vinculados ao denominado Núcleo de Estudos Biogeográficos de Rio Claro na orientação e condução das pesquisas, tanto no estado de São Paulo como em outros estados, acabou naturalmente compondo o rol dos objetivos. A gênese da Biogeografia deu-se pelos esforços de pesquisadores que se dedicaram à investigação sobre a distribuição dos seres vivos, desde os primórdios, tais como os naturalistas, mas seu desenvolvimento e evolução somente foram possíveis pela dedicação de outros pesquisadores, como os do Núcleo de Estudos Biogeográficos de Rio Claro, sobretudo quanto à investigação sobre o relacionamento e funcionamento global das Biogeocenoses e dos Geossistemas. / The objective of this study was recovery the academic production in Biogeography, developed since 1969 until 2004, by professors, researchers and students of the Geography Department, Master and Doctor Degree of Geography Program, Geosciences and Accurate Sciences Institute of São Paulo State University, at Rio Claro, more directly involved with Biogeography subjects. Before this investigation, a systematic analysis and estimation of the contributions and originalities were made, and a classification of the works in the specific disciplines in Biogeography as well, for the purpose to identify the more contemplate areas and those that are showing more progress. It was given also an emphasis to the analysis of the space and the scales more common in these researches. Spreading the importance of the researchers in Nucleus of Biogeography Studies at Rio Claro to the development and conduction of these researches was a natural process of this work. The Biogeography's genesis was possible due the efforts of the researchers, since a long time, in studying alive-beings' distribution, like the naturalists did. But the development and evolution only had continuity by the dedication of other researchers (the Rio Claro's researchers, for example) in studies about the relationship and the global functionality of the Biogeocenoses and Geossystems.
83

Heterogeneidade das comunidades de morcegos da Mata Atlântica brasileira

Silva, Emmanuel Messias Vilar Gonçalves da 27 March 2015 (has links)
Submitted by FABIANA DA SILVA FRANÇA (fabiana21franca@gmail.com) on 2017-12-20T15:24:12Z No. of bitstreams: 1 Arquivo Total.pdf: 8515282 bytes, checksum: 4c0688932ebc2cf358d850e2dd846f4e (MD5) / Made available in DSpace on 2017-12-20T15:24:12Z (GMT). No. of bitstreams: 1 Arquivo Total.pdf: 8515282 bytes, checksum: 4c0688932ebc2cf358d850e2dd846f4e (MD5) Previous issue date: 2015-03-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The Atlantic Forest is home bristle 1-8% of all the flora and fauna of the world. In particular bats this biome represent about 64% of all species of bats in Brazil. Data on the composition and abundance of species of bat communities have never been synthesized and analyzed, as well as data about the spatial distribution and structure of bat communities in this biome, especially as their dissimilarity in a meta community perspective that can be broadly defined as a set of ecological communities in different locations (potentially, but not necessarily connected by dispersion), while a community is a group of species in a given location. In view of this I sought to evaluate the spatial pattern of collections made in this biome and the structuring of bat communities along the Brazilian Atlantic Forest, as its beta diversity. Therefore gather a database of 57 articles totaling 342 locations through literature review. Realized statistics focused on spatial distribution of sampling, the sampling effort (median: 19140h.m²) and for the analysis of beta diversity and metacomunidades. The results show that there are collections across the Atlantic Forest with higher density in PR outbreaks, south of Rio de Janeiro, PB-PE, south of Bahia. Sampling gaps are reported in ES, AL, CS and RS. The bat communities along the Brazilian Atlantic Forest has a high heterogeneity (~0.9) mainly due to the turnover component and a low component of nesting. This result is valid for analysis in four spatial scales: locations, grid 2.5°, 5 and between 4 biogeographic regions of the Atlantic. The structure of arrays of occurrence of species per sample unit (as defined above) presentam a random structure (non-coherent) without latitudinal gradient. Four inventories were conducted in four biogeographical regions of the Atlantic Forest biome within the project Network Inventory: diversity patterns, biogeography and endemic species of mammals, birds, amphibians, fruit flies and parasites in the Atlantic Forest (CNPq / PPBIO) in the rainy season totaling a 99.600 h.m² effort. 935 bats were collected, and tissue samples for DNA extraction purpose and parasitological diagnosis of trypanosomes (T. cruzi et Leishmania spp.), Hantavirus and helminths. The place with the highest species richness was the APA Pratigi BA, followed by Rebio Guaribas, PB; Serra dos Orãos, RJ State Park and the Sierra Board, SC. Recorded the first occurrence of the bat Ametrida centurio Grey, 1847 for the Atlantic Forest, extending its distribution in more than 1000 km. The specimen was collected using canopy networks to 9m in REBIO Guaribas. / A Mata Atlântica abriga cerda de 1-8% de toda a flora e fauna do mundo. Em particular os morcegos deste bioma representam cerca de 64% do total de espécie de quirópteros do Brasil. Dados sobre a composição e abundância de espécies de comunidades de morcegos nunca foram sintetizados e analisados, assim como dados a cerca da distribuição espacial e estruturação das comunidades de morcegos neste bioma, sobretudo quanto a sua dissimilaridade sob uma perspectiva de metacomunidade que pode ser amplamente definida como um conjunto de comunidades ecológicas em locais diferentes (potencialmente, mas não necessariamente ligados por dispersão), enquanto que uma comunidade é um grupo de espécies em um determinado local. Em vista disto busquei avaliar o padrão espacial de coletas realizadas neste bioma e a estruturação das comunidades de morcegos ao longo da Mata Atlântica brasileira, quanto a sua beta diversidade. Para tanto reuni um banco de dados de 57 artigos somando 342 localidades através de revisão da literatura. Realizei estatísticas voltadas a distribuição espacial de coletas, do esforço amostral (mediana: 19140h.m²) e para a análise de beta diversidade e metacomunidades. Os resultados apontam que existem coletas em toda a Mata Atlântica com focos de maior densidade no PR, sul do RJ, PB-PE, sul da BA. Lacunas de amostragem publicadas se encontram no ES, AL,SC e RS. As comunidades de morcegos ao longo da Mata Atlântica brasileira tem uma heterogeneidade alta (~0.9) explicada principalmente pelo componente de Turnover e com um baixo componente de aninhamento. Este resultado é valido para analises em 4 escalas espaciais: localidades, grades de 2,5º, 5º e entre as 4 regiões biogeográficas da Mata Atlântica. A estruturação das matrizes de ocorrência de espécies por unidade amostral (como definido acima) apresentam uma estruturação aleatória (não coerente), sem gradiente latitudinal. Oito inventários foram realizados nas quatro regiões biogeográficas da Mata Atlântica dentro do projeto Rede BioMA Inventários: Padrões de diversidade, biogeografia e endemismo de espécies de mamíferos, aves, anfíbios, drosófilas e parasitos na Mata Atlântica (CNPq/PPBIO) na estação chuvosa totalizando um esforço de 99.600 m²h. Foram coletados 935 morcegos, assim como amostras de tecidos para fins de extração de A.D.N. e de diagnósticos parasitológicos de tripanossomatideos (T. cruzi et Leishmania spp.), Hantavirus e Helmintos. A localidade com maior riqueza de foi a APA do Pratigi BA, seguido da Rebio Guaribas, PB; Serra dos Orãos, RJ e Parque Estadual da Serra do Tabuleiro, SC. Registrei a primeira ocorrência do morcego Ametrida centurio Grey, 1847 para a Mata Atlântica, estendendo sua distribuição em mais de 1000 quilômetros. O espécime foi coletado utilizando redes de dossel a 9m na REBIO Guaribas.
84

Etnobotânica de Passiflora L. uma aproximação na biogeografia, agroecologia e conservação dos maracujazeiros / Ethnobotany of Passiflora L. an approach in biogeography, agroecology and conservation of passionfruits

Villamil Montero, Daniel Antonio [UNESP] 03 February 2017 (has links)
Submitted by DANIEL ANTONIO VILLAMIL MONTERO null (dvillamontero@fca.unesp.br) on 2017-07-17T04:38:29Z No. of bitstreams: 1 TeseDAVM_julho.pdf: 9783024 bytes, checksum: 5e47b7548f0a031f8c1c3c3ddbc72902 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-07-19T16:34:48Z (GMT) No. of bitstreams: 1 villamilmontero_da_dr_bot.pdf: 9783024 bytes, checksum: 5e47b7548f0a031f8c1c3c3ddbc72902 (MD5) / Made available in DSpace on 2017-07-19T16:34:48Z (GMT). No. of bitstreams: 1 villamilmontero_da_dr_bot.pdf: 9783024 bytes, checksum: 5e47b7548f0a031f8c1c3c3ddbc72902 (MD5) Previous issue date: 2017-02-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As relações e interações entre os seres humanos e as passifloras são múltiplas e complexas, incluindo casos como a domesticação, dispersão, aproveitamento e depredação de espécies (entre outras). Dada sua importância econômica, as passifloras constituem um recurso genético muito importante e a caracterização de populações silvestres e cultivadas é uma prioridade para os países neotropicais que albergam a maior diversidade do gênero. Mais de 80 espécies produzem frutos comestíveis e pelo menos 37 são cultivadas local e regionalmente. A implementação de estratégias para a conservação e o aproveitamento destes recursos fitogenéticos são necessárias, devido ao seu potencial para o desenvolvimento e diversificação de agricultura. O estudo aprofundado das relações humanas com as plantas cultivadas do gênero Passiflora pretende contribuir com delineamentos para programas de conservação da biodiversidade de passifloráceas. Neste trabalho são abordadas informações agroecológicas, biogeográficas e etnobotânicas correspondentes às espécies úteis de Passiflora. / Relationships and interactions between humans and passionflowers are multiple and complex, including cases such as domestication (among others). Due to their economic importance, passiflowers constitute a very important genetic resource and the characterization of wild and cultivated populations is a priority for Neotropical countries that have the greatest diversity of the genus. More than 80 species produce edible fruits and at least 37 are grown locally and regionally. The implementation of strategies for the conservation and utilization of these genetic resources are necessary due to their potential for the development and diversification of agriculture. A depth study of cultivated plants of the genus Passiflora intends to contribute with designs for programs of conservation of the biodiversity of Passifloracea. In this work the agroecological, biogeographic and ethnobotanical information corresponding to the useful species of Passiflora are presented and discussed.
85

Výuka biogeografie a ochrany životního prostředí na základní škole / Teaching of Biogeography and environmental Protection at the Primary School

DVOŘÁKOVÁ, Stanislava January 2010 (has links)
The theme of this diploma thesis is the "Tcheaching of Biogeography and environmental Protection at the Primary School". The thesis is specifically concerned with the elaboration of alternative teaching material for primary schools that can be applied for lessons geography, natural science, as well as interest Gross and seminars. It also represents a source of inspiration and information for teachers. The thesis proceeds from the Framework Education Programme for Basic Education namely from the field of education "Human and Nature" and topical spheres such as "Natural View of the Earth" and "Environment". It complies with the sectional theme "Environmental Education". This thesis includes an analysis and assesment of selected geography textbooks for the 2nd stage of primary school. The main assessment criteria were the quality of subjekt matter processing and textbook structure. Furthermore, the thesis comprises of text part, worksheets, and thein key solutions.
86

Range size heritability patterns in Carnivora arise from the interplay between evolutionary and geographic constraints

MACHÁČ, Antonín January 2011 (has links)
The thesis explores how the range sizes of carnivorans are shaped by geographic and evolutionary constraints. Employing modern spatial analyses and phylogenetic comparative methods, we illustrate that phylogenetically conserved climate tolerances delimit species? geographic constraints, which in turn shape the species? range size. Range size heritability patterns emerge as a consequence of this interplay between geographic and evolutionary constraints.
87

Padrões de riqueza, diversidade e endemismo de répteis e anfíbios na América do Sul / Patterns of richness, diversity and endemism of reptiles and amphibians in South America

Mauro Teixeira Junior 11 August 2017 (has links)
O nosso conhecimento sobre a distribuição das espécies vem avançando desde as primeiras observações feitas séculos atrás. Recentemente uma melhoria nos métodos e na cobertura geográfica das amostragens tem melhorado significativamente nosso conhecimento sobre padrões de distribuição. O que tem permito diversos tipos de análises, revelando padrões macroecológicos com os observados aqui onde riqueza de répteis e anfíbios apresenta uma forte relação com o ambiente, sendo maiores em aras mais baixas, com temperatura e precipitação estáveis e maior estrutura no ambiente, enquanto que para endemismo e diversidade beta a relação é mais fraca. Porém este conhecimento sobre a distribuição das espécies não está homogeneamente distribuído por todas as regiões, sendo especialmente baixo na região Amazônica, que é justamente a região que abriga a maior riqueza local de espécies, estando concentrado ao longo das margens dos rios. Isto que pode indicar que os valores que temos disponíveis ainda são subestimados, e que quaisquer inferências sobre estes valores devem ser interpretados com cautela / Our knowledge on species distribution has advanced since the first observations made centuries ago. Recently the improvement on techniques and geographical coverage of samplings activities has improved significantly our knowledge on distribution patterns. This advance has allowed several analyses to be done, and macroecological patterns to emerge, such as the one observed ibn here with reptile and amphibian richness presenting a strong relationship with environmental conditions, with higher values at lower areas, with more stable precipitation and temperature, an higher environmental structure, while endemism and beta diversity have a weaker signal. However the knowledge on species distribution is not homogeneously distributed across all regions, being especially low at the Amazon, which is precisely the area that harbors the highest richness values, being concentrated at the rivers\' shores, suggesting that the values we have today may be far underestimated, and thus any inference using them should be interpreted with caution
88

Assessing the Habitat of Coccidioides Posadasii, the Valley Fever Pathogen: A Study of Environmental Variables and Human Incidence Data in Arizona

Mann, Sarina N., Mann, Sarina N. January 2017 (has links)
Coccidioidomycosis, or Valley Fever, is an infectious disease caused by inhalation of soil-dwelling fungus Coccidioides posadasii spores in the Lower Sonoran Life Zone (LSLZ) in Arizona. In the context of climate change, the habitat of environmentally-mediated infectious diseases, such as Valley Fever, are expected to change. Connections have been drawn between climate and Valley Fever infection. The operational scale of the organism is still unknown. Here, we use climatic variables, including precipitation, soil moisture, and temperature. We use PRISM precipitation and temperature data, and Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) as a measure of soil moisture for the entire state of Arizona, divided into 126 primary care areas (PCA). These data are analyzed and regressed with Valley Fever incidence to determine the effects of climatic variability on disease distribution and timing. This study confirms that Valley Fever occurrence is clustered in the LSLZ. Seasonal Valley Fever outbreak was found to be variable year-to-year based on climatic variability. The inconclusive regression analyses indicate that the operational scale of Coccidioides is smaller than the PCA region. All variables are related to Valley Fever infection, but one variable was not found to hold more predictive power than others.
89

Taxonomy, Systematics, and Venom Components of Neobisiid Pseudoscorpions (Pseudoscorpiones: Neobisiidae)

Hughes, Garrett Brady, Hughes, Garrett Brady January 2017 (has links)
Pseudoscorpions are a diverse lineage of arachnids with a rich history of taxonomic study. However, they remain one of the lesser-known groups of arachnids and many questions about these enigmatic arthropods remain. The present work revises the taxonomy and systematics of the family Neobisiidae in the Southwest, documenting the existence of several new species and a hitherto unknown clade from the Sky Island region of southeastern Arizona. It also describes the venom of a pseudoscorpion for the first time, through comparative transcriptomic studies. Seven new species are described and assigned to the genus Globocreagris, extending the known range of this genus from California into Arizona, Oregon, and Washington. The monophyly of the subfamily Neobisiinae was tested using two genes (COI and 28S). Molecular phylogenetic analysis of both genes and the pattern of trichobothrial placement on the chelae supports removing Parobisium from the subfamily Neobisiinae, and placing it within the subfamily Microcreagrinae, a reassignment here made. Although it has long been known that most pseudoscorpions possess venom glands in their pincers which they use to subdue their arthropod prey, the components of the venom have never been identified. Using comparative transcriptomics from the pedipalps of Globocreagris the first putative venom proteins in pseudoscorpions were identified. Putative venom proteins include astacin-like metalloproteases, chitinases, cysteine-rich secretory proteins, Kunitz-type serine protease inhibitors, phospholipase A2, and scorpion La1-like peptides.
90

Studies on the diversity and spatial distribution of deep-water sponges along the west and south coasts of South Africa

Maduray, Seshnee January 2013 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / This thesis explores the diversity, spatial patterns and community structure for the sponges (Porifera) along the west and south coasts of South Africa. Species collected were identified to the lowest level of lowest taxonomic unit possible (either species or genus). The study site was divided into areas and in each of these we documented the spatial diversity and in so doing were able to assess the variation of sponge communities between the west and south coasts. The total number of species recorded for this deep-water region was eighty-three of which nineteen are described. The south coast was more diverse than the west coast and eleven species were found to be common to both coasts. The analysis based on location and depth showed that both coasts are significantly different to each other. We determined that these areas are biogeographically separated. Species contributing toward the dissimilarity between both coasts include Suberites carnosus, Myxilla (Burtonanchora) sp 1, Rossella antarctica, Tetilla capillosa and Haliclona sp. Patterns of species richness showed an increase in diversity from the west to south. It was found that species richness increases with depth for both coasts but only up to 350 m for the west coast and 200 m for the south coast. However, the sampling effort was determined to possibly have not been enough to gain a full understanding of species richness for the entire study area as the number of species was correlated with sampling effort. Estimated richness found that higher richness of sponges could still be found within most of the best bins and for each coast. An estimate of samples needed both each depth bin per coast showed that more samples would be needed on the south coast and this is possibly due to the greater variety and variability of the species found on the coast. The sponge community on the south coast was found to have no significant difference in pattern with some of the depth bins, whereas depth plays a role in sponge community on the west coast. Species of Suberites were dominant at depths lower than 200 m while Hamacantha (Vomerula) esperioides was dominant between 200 and 350 m with Tetilla capillosa dominated depths lower than 350 m. The thesis is concluded with an overview of what is now known and what still needs to be discovered and determined to further enhance biodiversity knowledge in the country.

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