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Growth induced export has become a major concern for policy makers to transform and upgrade the export composition to achieve economic growth objectives; in this respect, export diversification become at the heart of growth induced export narrative. Nevertheless, this study attempts to find relationship between export diversification and economic growth. To investigate this relationship, a cross-section method is used with averaged data from the period 1991 to 2009 of 41 sub Saharan Africa countries; moreover, diagnostic tests were conducted to ensure the robustness of the model. The empirical result of this study shows positive correlation between export diversification and economic growth which can be concluded that export diversification promotes economic growth.

The Tropical Andes make up Earth's most species-rich biodiversity hotspot for both animals and plants. Nevertheless, the ecological and evolutionary processes underlying this extraordinary richness remain uncertain. Here, we examine the processes that generate high richness in the Tropical Andes relative to other regions in South America and across different elevations within the Andes, using frogs as a model system. We combine distributional data, a newly generated time-calibrated phylogeny for 2,318 frog species, and phylogenetic comparative methods to test the relative importance of diversification rates and colonization times for explaining Andean diversity at different scales. At larger scales (among regions and families), we find that faster diversification rates in Andean clades most likely explain high Andean richness. In contrast, at smaller temporal and spatial scales (within family-level clades within the Andes), diversification rates rarely explain richness patterns. Instead, we show that colonization times are important for shaping elevational richness patterns within the Andes, with more species found in habitats colonized earlier. We suggest that these scale-dependent patterns might apply to many other richness gradients. Recognition of this scale dependence may help to reconcile conflicting results among studies of richness patterns across habitats, regions, and organisms.

Agriculture has not been a mean of securing a food for nations for a long time. Today, thanks to the European union policy, the business activities of agricultural enterprises head towards to the energetics industry and to other industries like heating, forestry or services that enable the companies to diversify their activities beyond the borders of the primary sector. The reasons for a decision of extending the strategic focus of business are many: smaller dependency on weather, better market position in the relevant micro environs, more effective use of agricultural land, local energetic self-sufficiency. This thesis analyses especially the transition of the Czech agriculture from the concept of securing the food self-sufficiency of the state towards to the concept of securing energetic self-sufficiency of the state, facilitated by the renewable energy sources produces by farmers, and other development trends in the Czech agriculture in the European transnational, Czech national and local business context.

Comprendre l'émergence des patrons de richesse biologique sur Terre intéresse les écologues et les biologistes de l'évolution depuis des décennies. La diversité en un lieu résulte d'une combinaison de processus liés à la diversification, à la dispersion et au temps. Afin d’évaluer le rôle relatif de ces différents facteurs pour mieux comprendre comment les patrons de diversité se sont mis en place, nous utilisons ici les méthodes les plus récentes basées sur des phylogénies moléculaires. Dans une première partie, nous nous sommes intéressés au gradient latitudinal de diversité des mammifères: le fait qu'il y ait plus d'espèces dans les régions tropicales que dans les régions tempérées. Pour les mammifères, nous montrons que dans les tropiques, la spéciation est plus forte, et l'extinction plus faible que dans les zones tempérées. Chez les carnivores, cependant, nous montrons que le gradient latitudinal de diversité pourrait être indépendant des taux de diversification, mais plutôt expliqué par une dispersion forte des zones tempérées vers les zones tropicales. Dans une deuxième partie, nous nous sommes intéressés à l'identification de facteurs intrinsèques et extrinsèques pouvant jouer un rôle dans la diversification des lignées. Nous avons choisi d'étudier l'impact de la migration sur la diversification des oiseaux et l'impact de la température sur la diversification des mammifères. Dans une dernière partie, et dans le contexte du réchauffement climatique actuel, nous nous sommes interrogés sur la façon d'utiliser les outils phylogénétiques pour conserver la biodiversité. / Understanding how specific richness is distributed on Earth has been a priority for ecologists and evolutionary biologists for decades. Species richness in a given place results from a combination of processes linked to diversification rates, dispersal rates, and time. In order to evaluate the relative role of these different factors and gain a better understanding of how biodiversity patterns have been shaped, we use up-to-date methodologies, based on molecular phylogenies. The first part concerns the latitudinal diversity gradient, that is how species richness decreases from the tropics to the temperate regions. For mammals, we show that speciation is higher and extinction lower in the tropics than in temperate regions. For Carnivora, however, we show that the latitudinal diversity gradient could be independent from diversification rates, and rather explained by high rates of dispersal from temperate to tropical regions. The second part is focused on the identification of intrinsic and extrinsic factors that might play a role in the diversification of lineages. We study the impact of migration on bird diversification and the impact of temperature on mammal diversification. Finally, we investigate if and how phylogenetic inference tools can be useful for the conservation of biodiversity in a changing world.

Os gêneros Nycticalanthus (monotípico) e Spiranthera (quatro espécies), pertencentes à família Rutaceae, tribo Galipeeae, são semelhantes morfologicamente e possuem distribuição restrita à América do Sul. São predominantemente arvoretas ciófilas de florestas úmidas, exceto Spiranthera odoratissima, que possui hábito arbustivo savânico e é a espécie de distribuição mais ampla, com a maior variabilidade morfológica. Este estudo teve como objetivo investigar as relações de parentesco entre Nycticalanthus e Spiranthera e suas espécies, utilizando dados moleculares (região ETS do DNA nuclear e espaçador trnL-F do DNA plastidial), visando entender os processos subjacentes à sua diversificação e biogeografia, além de realizar uma revisão taxonômica do grupo. Baseado na filogenia obtida e nas características morfológicas compartilhadas entre as espécies de ambos os gêneros, muitas delas sinapomórficas, é proposta a sinonimização do gênero monotípico Nycticalanthus sob Spiranthera. A revisão taxonômica apresentada baseia-se em uma extensa análise morfológica do grupo, incluindo expedições a campo e estudo de espécimes de herbários, elaboração de chave de identificação, descrição e ilustrações das seis espécies reconhecidas, incluindo uma espécie nova de Iquitos, Peru, além de dados de distribuição geográfica, habitats e variabilidade morfológica de cada táxon / The genera Nycticalanthus Ducke (monotypic) and Spiranthera A.St.-Hil. (four species), belonging to Rutaceae, tribe Galipeeae, are morphologically similar and restricted to South America. They are mostly sciophyllous treelets from rainforests, except for Spiranthera odoratissima, the most widespread species, which is a shrub inhabiting savannic formations and showing the highest morphological variation. This study investigated the phylogenetic relationships between the two genera, and among their species as well, using molecular data (ETS from the nuclear DNA, and trnL-F spacer from the plastidial DNA), aiming at understanding the processes involved in their diversification and biogeographic history. I also studied the taxonomic circunscription of both genera (all species included) carrying out a taxonomic revision of them. Based on the phylogeny and morphological characteristics shared by the species of both genera (most of them synapomorphies), I have proposed the synonymization of the monotypic genus Nycticalanthus under Spiranthera. The taxonomic revision is based on extensive morphological analysis of the group, including collecting and observation during field trips, and study of herbarium specimens. I also present identification keys, descriptions and illustrations for all the six species, including a new one from Iquitos, Peru, as well as updated geographic distribution range, habitats, and discussion about the morphological variation of each taxon

As angiospermas são um dos grupos mais diversos de organismos, e grande parte dessa diversidade deve-se às muitas formas florais existentes. Devido a isso, determinar os padrões de variação floral e os fatores históricos e ecológicos que levaram à evolução desta alta diversidade floral é essencial para entender os processos que dirigem a diversificação das angiospermas. A tribo Bignonieae (Bignoniaceae) representa um excelente modelo para o estudo de diversificação floral na região Neotropical, por ser o clado mais diverso de lianas neotropicais e apresentar uma altíssima diversidade floral. Nesta tese, utilizei a tribo Bignonieae para caracterizar: (i) o padrão de evolução de caracteres florais discretos e morfologias florais, assim como possíveis associações entre as morfologias florais e grupos de polinizadores, (ii) o sinal filogenético e as taxas de evolução de caracteres florais contínuos, (iii) o padrão e a magnitude de integração fenotípica entre caracteres florais contínuos ao longo da filogenia do grupo e (iv) a influência da filogenia, da morfologia floral e de fatores abióticos para a co-ocorrência de espécies e a estrutura de comunidades de Bignonieae. Os resultados indicam grande labilidade na evolução de caracteres discretos e morfologias florais, contrapondo o sinal filogenético encontrado para os 16 caracteres contínuos avaliados. O sinal filogenético, entretanto, difere entre caracteres de cálice-corola e estame-estigma. As taxas de evolução também variam entre caracteres, indicando a ação de diferentes pressões seletivas ou resposta diferencial à seleção em diferentes partes da flor. Os padrões de integração fenotípica se mantêm constantes ao longo da história evolutiva de Bignonieae, apesar da evolução homoplástica da magnitude das correlações entre caracteres. Essa aparente complexidade evolutiva, sugerida pela presença de padrões diferentes em diferentes tipos de caracteres, não se repete na estrutura ecológica das comunidades, já que nem a morfologia floral e nem a filogenia influenciam a co-ocorrência entre espécies. Por outro lado, há evidente especialização das espécies a fatores abióticos, sugerindo um papel crítico de filtro ambiental na estrutura das comunidades de Bignonieae. Esse resultado contraria a hipótese de que saturação causada por competição por polinizadores seria o fator determinante da estrutura interna de comunidades de Bignonieae. / Flowering plants represent one of the most diverse groups of organisms in the Planet. A large portion of this diversity results from the multitude of floral forms encountered nowadays. To understand the patterns of floral variation and of the historical and ecological factors that led to the evolution of such diversity in floral forms are critical for a better understanding of the processes that led to the diversification of angiosperms. The tribe Bignonieae (Bignoniaceae) is the most diverse clade of Neotropical lianas and represents an excellent model for the study of floral evolution due to the high diversity of floral forms of this group. In this Ph.D. thesis, I aimed to characterize: (i) the pattern of evolution of discrete floral traits and floral morphologies in Bignonieae, as well the potential associations between floral morphologies and pollinators; (ii) the phylogenetic signal and the rates of evolution of continuous floral traits; (iii) the pattern and the magnitude of phenotypic integration among floral traits across the phylogenetic history of the group; and, (iv) the influence of phylogeny, floral morphology and abiotic factors for the patterns of species co-occurrence and the structure of communities of Bignonieae in the Neotropics. The results indicate high lability in the evolution of discrete floral traits and floral forms, contrasting the significant phylogenetic signal encountered in all 16 continuous floral traits examined. However, the phylogenetic signal differs between traits of different floral whorls. The rates of evolution also varied among different characters, suggesting the action of different selective pressures or differential responses to selection in different floral parts. Overall, the patterns of phenotypic integration were constant during the history of Bignonieae, despite the homoplastic evolution of the magnitude of correlation among characters. This apparent evolutionary complexity, leading to different patterns in different traits, is not reflected in the ecological structure of communities, given that nor floral morphology or phylogeny influence species co-occurrence. On the other hand, species specialization to abiotic factors was encountered, suggesting that environmental filtering played a key role in the structure of communities of Bignonieae. The results reject the hypothesis that saturation caused by competition for pollinators would be the main factor determining the intra-community structure of Bignonieae.

京都大学 / 0048 / 新制・課程博士 / 博士(地域研究) / 甲第22568号 / 地博第271号 / 新制||地||103(附属図書館) / 京都大学大学院アジア・アフリカ地域研究研究科アフリカ地域研究専攻 / (主査)教授 重田 眞義, 教授 高橋 基樹, 准教授 大山 修一, 准教授 金子 守恵 / 学位規則第4条第1項該当 / Doctor of Area Studies / Kyoto University / DGAM

Marginal communities living in semi-arid Namibia face significant challenges in sustaining rural livelihoods due to environmental degradation and poverty. Research has shown that livestock farming depends on rain-fed agriculture among other things, thus making communal farmers vulnerable to climate change in the future. Given this, it often makes sense for farmers to sell their livestock and explore alternative livelihood options. However, farmers in northcentral Namibia are reluctant to sell their livestock despite a noticeable temperature increase and rainfall decrease over the past forty years. This study analyses the barriers to selling livestock in the face of a drought in the Omusati region of north-central Namibia. The study was carried out in three villages namely Omahanene, Okathitukeengombe and Oshihau, in the north-central Omusati region of Namibia. Household livestock distribution, perceptions of climate change, barriers to the sale of livestock and alternative livelihood strategies from other semi-arid regions were explored among 30 households using semi-structured household interviews and a systematic literature review. Results from the study indicate that 80% of communal farmers predict future droughts in the region and able to recall climate change through frequent droughts, increasing temperatures and decreasing rainfall. Farmers claimed that these changes have affected their livestock numbers. However, several barriers including cultural beliefs, lack of financial security, access to information, lack of institutional support and lack of efficient markets hinder livestock sales. The study suggests that the imminent impact of climate change coupled with the reluctance to sell livestock will threaten food security in the future. The study argues that rural livelihood diversification strategies are critical to safeguarding sustainable livelihoods in the future, including those of communal livestock farmers specifically. Additionally, policy recommendations like access to credit through public and private funding, access to markets by providing transportation facilities, encouraging market participation by improving quality of grazing lands, increasing water availability, building veterinary facilities, employing extension officers and access to information through reliable channels can help build a sustainable future in the face of climate risks.

Corporate strategy forms the platform to consider fundamental strategic alternatives for an organisation. The recent financial crisis has been a sobering reality check for most companies. Diversification or specialisation are two of the more common configurations that corporate strategy theory would propose to grow and sustain financial performance, particularly during though times. Research conducted in developed markets since the 1950’s have tried to establish if diversification creates or destroys value. Conglomerates, defined as unrelated diversification, are often believed to translate into diversification discounts in developed economies. The application of this theory has been questioned with respect to emerging markets and the empirical results in these markets have been mixed. A conceptual approach using different approaches, institutional, resourcebased, adaptive and learning theories was used to try and explain the deviation in results attained by conglomerates within emerging markets and those in developed markets. Specific arguments and propositions were developed based on these different theoretical lenses for South Africa. These propositions were tested by statistical analysis of organisations listed on the Industrial sector of the Johannesburg Securities Exchange (JSE). The organisations were categorised into conglomerates or focused groups. The two groups were compared in terms of financial measures from the period 2001 to 2009 to determine which group performed better. / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted