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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

Maternal Phylogeography Of Brown Bears (ursus Arctos) And Testing The Utility Of Non-invasive Genetic Samples

Cilingir, Fatma Gozde 01 October 2012 (has links) (PDF)
The genetic diversity and phylogeography of brown bear maternal lineages have been studied extensively over the last two decades. In this study the genetic diversity and maternal phylogeography of non-invasively sampled 35 brown bears, including 5 captive individuals were reported from Turkey. In addition to the optimization of DNA extraction from hair, faeces and old skin samples and their PCRs, Bayesian phylogenetic analyses based on a 269 bp long piece of bear mitochondrial DNA were conducted and 14 novel haplotypes belonging to three major lineages were revealed. The most widespread lineage was found to be the &ldquo / Eastern&rdquo / clade 3a, while geographically more restricted &ldquo / Western&rdquo / and &ldquo / Middle Eastern&rdquo / lineages were reported for the country for the first time. A specimen from the Taurus range (southern Turkey) was shown to be closely related to the presumably extinct bears in Lebanon. Moreover, a unique novel lineage that appears to have split early within the Middle Eastern clade was defined. Despite limited sampling, this study demonstrates a high level of mitochondrial diversity in Turkish brown bears, extends the ranges of both European and Middle Eastern clades into Turkey, and identifies a new divergent lineage of possibly wider historical occurrence while demonstrating the significance of non-invasive genetic sampling for such analysis.
2

Genetic Assessment of the Malayan Tapir (Tapirus indicus) for Its Conservation Implications / マレーバク(Tapirus indicus)の保全を目指した遺伝解析

LIM, Qi Luan 23 March 2023 (has links)
付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院 / 京都大学 / 新制・課程博士 / 博士(理学) / 甲第24471号 / 理博第4970号 / 新制||理||1709(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 村山 美穂, 教授 伊谷 原一, 教授 平田 聡 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
3

Reproductive Isolation and Genetic Divergence in a Young "Species Flock" of Pupfishes (Cyprinodon sp.) from San Salvador Island, Bahamas

Bunt, Thomas Michael 14 February 2002 (has links)
The study of the process of speciation is instrumental to understanding the species diversity observed today. Diverging populations are intriguing, because speciation has not reached an endpoint, yet the process that may eventually lead to distinct species can be studied. Systems that contain many putative species and/or parallel divergences, such as many species flocks and species pairs, are extraordinary examples of divergence and therefore are critical to the understanding of the speciation process. A "miniature" species flock of pupfish (Cyprinodon variegatus) discovered in lakes on San Salvador Island, Bahamas has evolved in less than 6 000 years, and is, therefore, important to the study of the pace of evolutionary processes. The San Salvador Island pupfish flock is composed of a normal form, which resembles coastal C. variegatus, and bulldog and bozo morphs, which diverge ecologically and morphologically from the normal morph. In Chapter 1, I sequenced the mtDNA control region and used haplotype frequency analyses to assess the level of differentiation between sympatric normals and bulldogs sampled from Osprey Lake and Little Lake on San Salvador Island. The bozo morph was too rare to include in the study. I also included samples of normals that occur in lakes without bulldog and bozo morphs to assess any differences between lakes on the island. All haplotype frequency comparisons for sympatric normals and bulldogs were highly significant, which suggests these morphs are distinct populations in sympatry and, therefore, have characteristics of biological species. Further, an estimation of Time for Speciation supports geological data that suggest this fauna is very young (6 000 years). The San Salvador Island pupfish species flock is, therefore, the youngest known species flock and presents an important model system for the study of how morphological and ecological divergence can promote speciation in Cyprinodon. In Chapter 2, I first compared the San Salvador Island pupfishes to other Bahamian C. variegatus populations to assess the level of inter- and intra-island pupfish population differentiation in the Bahamas. The mtDNA control region was sequenced for bulldogs and normals from San Salvador Island and normals sampled from New Providence and Exuma Islands. San Salvador Island bulldogs were found to be distinct from all normal populations sampled, and comparisons of shared haplotypes suggest they originated on San Salvador Island rather than any of the other islands sampled. This was intriguing, because a "bulldog-like" morph has recently been observed in a lake on New Providence Island, which suggests parallel divergences may be occurring throughout the Bahamas. I also sequenced the mtDNA cytochrome b gene to assess the phylogeography of C. variegatus. Populations were sampled from the Bahamas and the east coast of North America, and the results suggest the Bahamas were only recently colonized by the Southern coastal lineage of C. variegatus. A distinct Northern lineage of C. variegatus, which may warrant species designation, was also supported by the cytochrome b data. Overall, the results supported a San Salvador Island origin for the Little Lake and Osprey Lake bulldog morphs, and also suggest the Bahamian C. variegatus populations are very young. / Master of Science
4

Fylogeografie of Rousettus aegyptiacus ve Středomoří / Phylogeography of Rousettus aegyptiacus in the Mediterranean region

Dundarova, Cheliana January 2011 (has links)
The genus Rousettus has distributional pattern unique among fruitbats comprising both Asia and Africa and reaching northern distributional limits of the family in Persia, Arabia and Mediterranean basin. This could be ascribed to the ability of echolocation, consequent cave dwelling, and presumably other site-specific adaptations, which enabled dispersal independent of forest block and surviving in Mediterranean type of climate. Using fastly evolving mitochondrial marker, we aimed to assess genetic variability, its geographic distribution and demography of northern populations of the Egyptian fruitbat (Rousettus aegyptiacus). Mitochondrial network indicates deep genetic divergence between disjunct Mediterranean and eastern African parts of the range. Basal position of Sinaic and Jordanian haplotypes within northern clade indicate important role of these regions in colonization of eastern Mediterranean. Generally, the northern haplogroup is moderately diversified with partial geographic localization of particular haplotypes. Significant isolation by distance pattern suggests relatively pronounced site fidelity of particular colonies, at least in terms of maternal gene flow. Landscape genetics analyses indicate discontinuities in distribution of mitochondrial genetic variability, in some cases correlating with...
5

Estrutura genética populacional do camarão rosa Farfantepenaeus paulensis (Pérez-Farfante, 1967) nas costas sul e sudeste brasileira

Teodoro, Sarah de Souza Alves. January 2018 (has links)
Orientador: Rogério Caetano da Costa / Resumo: O camarão-rosa Farfantepenaeus paulensis é um dos mais importantes recursos pesqueiros da costa sul-sudeste do Brasil. Os fundos de pesca da espécie incluem dois estoques reprodutivos principais, localizados nas costas dos estados de Santa Catarina e São Paulo. A espécie apresenta ciclo de vida do tipo II, com uma fase reprodutiva no ambiente marinho e recrutamento juvenil em áreas estuarinas e baías. O conhecimento sobre o fluxo gênico entre estoques é a base de todo o ordenamento pesqueiro, uma vez que unidades genéticas podem apresentar características particulares e, normalmente, necessitam de estratégias específicas de manejo. Porém, há poucas informações que podem servir de subsídio para verificar se os diferentes estoques pesqueiros de F. paulensis também representam estoques genéticos distintos. O crescimento desordenado da frota industrial, o incremento da pesca artesanal nas áreas de criadouro, somado à pequena eficácia da legislação pesqueira, associados à ineficiência da fiscalização, levaram a um cenário de colapso da pescaria do camarão rosa no fim dos anos 90. Um melhor entendimento da estruturação genética das populações de F. paulensis é necessário, não somente pelo seu alto valor comercial e ecológico, mas também para permitir a implementação de medidas de manejo mais efetivas. Assim, o presente trabalho buscou avaliar a estruturação genética das populações do camarão rosa F. paulensis ao longo de sua distribuição no Atlântico Sul Ocidental, utilizando como ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The pink shrimp Farfantepenaeus paulensis is one of the most important fishing resources on the south-southeast coast of Brazil. The fishing zone of the species includes two main reproductive stocks, located on the coasts of Santa Catarina and São Paulo states. The species exhibits the type II life cycle, with an offshore reproductive stage and a juvenile recruitment in bays and estuarine areas. Knowledge on the amount of gene flow between stocks is the basis of all fisheries management, since genetic units may have particular characteristics and usually require specific management strategies. However, there is little information to verify whether F. paulensis's different fish stocks also represent different genetic stocks. The unrestricted growth of the industrial fleet, the increase in artisanal fishing in breeding areas, coupled with the low effectiveness of fisheries legislation and the inefficiency of inspection, led to a collapse of the pink shrimp fishery in the late 1990s. A better understanding of the genetic structuring of the populations of F. paulensis is necessary, not only for its high commercial and ecological value, but also to allow the implementation of more effective management measures. Thus, the present work aimed to assess the genetic structuring of the populations of the pink shrimp F. paulensis throughout its distribution in the Western South Atlantic, using as molecular marker the Control Region (D-loop) of the mitochondrial DNA (Chapter 1). In additi... (Complete abstract click electronic access below) / Doutor

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