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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.
1

Evolução de atributos reprodutivos em anuros / Evolution of anuran reproductive traits

Pereira, Elisa Barreto 14 March 2014 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-20T14:29:33Z No. of bitstreams: 3 Dissertação - Elisa Barreto Pereira - 2014.pdf: 8780558 bytes, checksum: 5fadc3e589faf51ab9607a5a6db9a3d4 (MD5) Dissertação - Elisa Barreto Pereira - 2014 - Anexos.pdf: 5906578 bytes, checksum: 1ba8fbf89d407670555f01497afd353c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-20T14:32:03Z (GMT) No. of bitstreams: 3 Dissertação - Elisa Barreto Pereira - 2014.pdf: 8780558 bytes, checksum: 5fadc3e589faf51ab9607a5a6db9a3d4 (MD5) Dissertação - Elisa Barreto Pereira - 2014 - Anexos.pdf: 5906578 bytes, checksum: 1ba8fbf89d407670555f01497afd353c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-10-20T14:32:03Z (GMT). No. of bitstreams: 3 Dissertação - Elisa Barreto Pereira - 2014.pdf: 8780558 bytes, checksum: 5fadc3e589faf51ab9607a5a6db9a3d4 (MD5) Dissertação - Elisa Barreto Pereira - 2014 - Anexos.pdf: 5906578 bytes, checksum: 1ba8fbf89d407670555f01497afd353c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-03-14 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Leptodactylinae frogs are a remarkable example of anurans outstanding diversity of reproductive features. The major distinctions among the four reproductive modes presented by this group are the relationship with water and the predicted gradual tendency towards terrestriality. To study the evolution of Leptodactylinae reproductive traits and recognize their patterns we used ancestral reconstruction methods. We also tested correlations among reproductive modes and other life-history traits by using stochastic inferences. First we reconstructed a phylogenetic hypothesis of Leptodactylinae lineages including Leptodactylus, Adenomera, and Lithodytes genera based on four DNA fragments. This hypothesis comprises the most complete phylogeny of Adenomera to date and confirm its monophyletism with Lithodytes as sister taxon. Our ancestral reconstruction analysis indicated that even though shifts from aquatic to terrestrial breeding occurred in the history of Leptodactylus and Adenomera, shifts from terrestrial to aquatic happened in almost the same frequency, indicating that Leptodactylinae frogs do not always evolve towards terrestriality and that reproductive modes with semi-terrestrial tadpoles is not necessarily an intermediate form between aquatic and terrestrial breed. Correlations among reproductive modes and other life-history traits suggest that tadpole environment, clutch size, nuptial spines, and egg pigmentation are coevolving driven by water dependence. / (Sem resumo)
2

UM ESTUDO DE SIMULAÇÃO A PARTIR DE DADOS DE MARCADORES MICROSSATÉLITES EM FRAGMENTOS DE Luehea divaricata Mart. & Zucc. NO BIOMA PAMPA / A SIMULATION STUDY FROM MICROSATELLITE MARKERS DATA ON Luehea divaricata Mart. & Zucc. FRAGMENTS OF THE PAMPA BIOME

Serrote, Caetano Miguel Lemos 21 August 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective was to use microsatellite DNA markers in simulations to study genetic, ecological and reproductive patterns that contributed to the genetic structure of five fragments of the forest tree species Luehea divaricata Mart. & Zucc, growing in the Pampa biome (Brazil). Various rates of selfing and migration were simulated. Selection criteria included observed and expected heterozygosity, whith values of 0,52 and 0,64, respectively (based on microsatellite markers). Reproductive mode was mixed, with a predominance of outcrosses (rate = 0,7), consistent with a self-incompatibility system in this species, which reduced but did not prevent self-fertilization. Migration at the rate of 0,02, implied existence of isolation by distance between fragments, which increased inbreeding coefficients. Based on Nei s gene diversity analysis, only 6% of genetic variability was distributed among fragments, with 94% inside them, due to the high outcrosses observed. Parameters for genetic conservation, namely, Minimum Viable Population and Minimum Viable Area, determined for conservation in the short and long terms, suggested that only the Inhatinhum fragment had the potential to maintain its genetic diversity in the short term. However, in the long term, none of the fragments proved feasible, thus requiring urgent intervention to prevent a decline, with creation of ecological corridors as a useful alternative to connect fragments through gene flow. The importance of computer programs for simulation of genetic, ecological and reproductive population parameters were clearly evident, demonstrating its potential for predicting future phenomena, thereby enabling identification of priority populations for conservation. / No presente trabalho foram utilizados dados de marcadores de DNA do tipo microssatélites em simulações para estudar padrões genéticos, ecológicos e reprodutivos que contribuíram para a estrutura genética de cinco fragmentos da espécie arbórea florestal Luehea divaricata Mart. & Zucc, em desenvolvimento em área brasileira do bioma Pampa. Várias taxas de autofecundação e de migração foram simuladas, tendo como critério de seleção a heterozigosidade observada e a heterozigosidade esperada, com valores de 0,52 e 0,64, respectivamente (com base em marcadores microssatélites). Os resultados permitiram caracterizar a população, quanto ao modo reprodutivo, como mista com predominância de cruzamentos (taxa = 0,7), sugerindo a presença de algum sistema de autoincompatibilidade nessa espécie, o qual reduz, mas não impede a autofecundação. A baixa migração (taxa = 0,02) sugere isolamento por distância entre os fragmentos, que aumentou os coeficientes de endogamia. Com base nos índices de diversidade genética de Nei, apenas 6% da variabilidade genética está distribuída entre os fragmentos e 94%, dentro, devido à elevada taxa de cruzamentos observada. Os parâmetros para conservação genética (População Mínima Viável e Área Mínima Viável), determinados para conservação em curto e longo prazo, sugerem que somente o fragmento da Fazenda Inhatinhum apresentou potencial para persistência em curto prazo. Porém, em longo prazo nenhum dos fragmentos se mostrou viável, necessitando assim de uma intervenção urgente de modo a evitar seu declínio, sendo a criação de corredores ecológicos uma alternativa útil para conectar os fragmentos através do fluxo gênico entre si. A importância dos aplicativos computacionais para a simulação de parâmetros genéticos, ecológicos e reprodutivos populacionais, foi claramente evidente no neste estudo, demonstrando seu potencial na antecipação de fenômenos futuros, permitindo, assim, a identificação de populações prioritárias para a conservação.

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