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In the biosonar systems of bats, emitted acoustic energy and receiver sensitivity are distributed over direction and frequency through beampattern functions that have diverse and often complicated geometries. This complexity could be used by the animals to determine the direction of incoming sounds based on spectral signatures. The present study in its first part has investigated how well bat biosonar beampatterns are suited for direction finding using a measure of the smallest estimator variance that is possible for a given direction (Cram{'e}r-Rao lower bound, CRLB). CRLB values were estimated for numerical beampattern estimates derived from 330 individual shape samples, 157 noseleaves (used for emission) and 173 outer ears (pinnae). At an assumed unit[60]{dB} signal-to-noise ratio, the average value of the CRLB was 3.9textdegree, which is similar to previous behavioral findings. Distribution for the CRLBs in individual beampatterns were found to have a positive skew indicating the existence of regions where a given beampattern does not support a high accuracy. The highest supported accuracies were for direction finding in elevation (with the exception of phyllostomid emission patterns). Beampatterns in the dataset were also characterized based upon the differences in the type of acoustic signal they are associated with, the functionality of the baffle shape producing them and their phylogeny. In the second part of the study, functionality of various local shape features was investigated under static and dynamic conditions. Each local shape feature was found to have an impact on the estimation performance of the baffle shape. Interaction of the local shape features among themselves as well as their dynamic motion produced a plethora of results, not achievable through either single features or through their static states only. / Ph. D.

The problem of biodiversity loss has been raised as a significant global issue for several years. There have been many significant attempts to cooperate at an international level. The Convention on Biological Diversity (CBD) was launched as a mechanism for multinational cooperation for global biodiversity conservation at international policy level among the signatory parties. Despite the formulation of the CBD, biodiversity policy has suffered in its framework, institution and practices. Biodiversity has continued being destroyed at a rapid rate. Previous research on biodiversity policy evaluation studied only some parts of the policy cycle but did not point out the strengths and weaknesses clearly leading to difficulties in holistic policy cycle of both formulation and implementation. This thesis evaluates effectiveness of biodiversity policy in Thailand as a signatory nation of CBD, principally in Indo-Burma and Sundaland biodiversity hotspots. They are important as a reservoir of the richest but most threatened plants and animals. While biosphere reserve has been established to allow locals utilising biodiversity as well as conservation, biodiversity threats have continuously been found. The policy was formulated and implemented to conserve them. The research was conducted to address this gap by thoroughly investigating the policy cycle in the development, implementation and evaluation of biodiversity policy, which truly reflecting political, socio-economic, cultural and environmental contexts. Thailand was taken as a case study and within this, three culturally diverse geographic locations were selected: North, Northeast and South biosphere reserves reflecting different ecosystems and cultures. This offered a detailed and complex analysis of development and implementation of the biodiversity policy throughout Thailand. An inductive approach and qualitative methods were applied using in-depth semi-structured and unstructured interviews with policy makers, decision makers, as well as focus groups with local stakeholders through the application of culturally sensitive policy evaluation methods. The findings suggested that biodiversity policy implementation failed in Thailand and policy formulation had a low level of participation from the locals. Local stakeholders demonstrated little engagement with the need for biodiversity information from the government. Bureaucrats, decision makers and policy developers also shared little enthusiasm for initiating effective policy. It is important that awareness raising and education enhancement, particularly with children so that they will learn from early age. At local level, the policy must be carefully implemented to engage local stakeholders in biodiversity conservation. It is significant that biodiversity policy will be effective if it applies a bottom-up approach and requires grassroots participation. The recommendations for biodiversity policy, in the long term, the government should take into account local views towards national policy and bring this to the international level to achieve sustainable biodiversity conservation. Thus, it offers new insights into the success or failure of biodiversity policy in developing countries that was affected by cultural factors which must be taken into account during the entire policy cycle by the international community.

Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Historical vicariant processes due to glaciations, resulting from the large-scale environmental changes during the Pleistocene (0.012-2.6 million years ago, Mya), have had significant impacts on the geographic distribution of species, especially also in marine systems. The motivation for this study was to provide novel information that would enhance ongoing efforts to understand the patterns of biodiversity on the South African coast and to infer the abiotic processes that played a role in shaping the evolution of taxa confined to this region. The principal objective of this study was to explore the effect of Pleistocene climate changes on South Africa′s marine biodiversity using five intertidal gastropods (comprising four rocky shore species Turbo sarmaticus, Oxystele sinensis, Oxystele tigrina, Oxystele variegata, and one sandy shore species Bullia rhodostoma) as indicator species. Sequence data obtained from partial segments of the mitochondrial cytochrome oxidase c subunit 1 (COI), and the nuclear ribosomal DNA (encompassing part of 5.8S, second Internal Transcribed Spacer and part of 28S, hereinafter called ITS2; or comprising part of the first Internal Transcribed Spacer, 5.8S, second Internal Transcribed Spacer and part of 28S, hereinafter called ITS), were used as genetic markers to construct phylogeographic patterns and to investigate demographic histories of the taxa. Population structure was investigated using haplotype network analyses, pairwise ΦST statistics, analysis of molecular variance (AMOVA), isolation by distance analyses, Bayesian analysis of population structure (BAPS) and coalescent analysis of gene flow. Demographic history was analysed through Fu′s Fs tests, mismatch distributions, and Bayesian skyline plots. Demographic analyses suggest that all five intertidal gastropods studied experienced demographic expansions dating to the late Pleistocene. The sandy shore direct developer B. rhodostoma began expansion after the LGM (c. 15 kya) whereas for the four rocky shore broadcast spawners (T. sarmaticus, O. sinensis, O. tigrina, and O. variegata) the onset of expansion coincided with or preceded the LGM (c. 25, 60, 50, 40 kya, respectively). Consistent with recent range expansions and gene flow patterns, the population genetic structure in all species was characterised by shallow or a lack of population differentiation. Oxystele variegata was an exception as it showed a deep disjunction, of late Pleistocene origin, between individuals in the west coast Namaqua Bioregion and those in the south coast Agulhas Bioregion. These results provide strong evidence of the vital role that Pleistocene climatic changes and current regimes played in shaping the nature and distribution of biodiversity on the South African coast. In addition, gene flow in all species, except O. tigrina, was remarkably asymmetrical with the regions around Cape Infanta and Port Elizabeth acting as source populations. Considering the generally weak population genetic structure and gene flow patterns detected for most gastropod species studied here, it is recommended that T. sarmaticus, O. sinensis, O. tigrina and B. rhodostoma be managed as panmictic populations, and that the region encompassing Cape Infanta, and Port Elizabeth should be prioritised for conservation as it appears to harbour source populations. Oxystele variegata was the only species showing distinct population structure and in this instance, species specific conservation efforts should recognize this divergence by treating the two genetic assemblages as distinct management units. / AFRIKAANSE OPSOMMING: Historiese vikariante prosesse kan toegeskryf word aan glasiasie, en het tot gevolg gehad dat grootskaalse veranderinge in die omgewing plaasgevind het tydens die Pleistoseen (,012 - 2.6 miljoen jaar gelede, Mjg). Dit het 'n beduidende impak gehad op die geografiese verspreiding van spesies, veral ook in die mariene stelsels. Die motivering vir hierdie studie was om nuwe data te voorsien wat sal bydrae tot die voortgesette pogings om die patrone van biodiversiteit langs die Suid-Afrikaanse kus te verstaan. Dit sou ook help om die abiotiese prosesse af te lei wat 'n rol gespeel het in die evolusie van taksa wat in hierdie streek voorkom. Die hoofdoel van hierdie studie was om die effek van die Pleistoseen klimaatsveranderinge op Suid-Afrika se mariene biodiversiteit te bepaal deur gebruik te maak van vyf intergety slak spesies as indikatore (vier wat in rotsagtige gebiede voorkom: Turbo sarmaticus, Oxystele sinensis, Oxystele tigrina, Oxystele variegata en 'n sanderige strand spesies: Bullia rhodostoma). Volgorde data verkry vanaf gedeeltelike segmente van die mitochondriale sitochroom oksidase c subeenheid 1 (COI), en die kern ribosomale DNA (bestaande uit 'n deel van 5.8S, tweede interne getranskribeerde spasieërders en 'n deel van 28S), hierna genoem ITS2 is gebruik as genetiese merkers om filogeografiese patrone te dokumenteer en ook om die demografiese geskiedenis van die spesies te ondersoek. Bevolking struktuur is ondersoek deur gebruik te maak van haplotipe netwerk analise, paarsgewyse ΦST statistiek, analise van molekulêre variansie (AMOVA), isolasie deur afstand analise, Bayesiaanse analise van die bevolking struktuur (BAPS) en analise van gene vloei. Demografiese geskiedenis is ontleed deur Fu se Fs toetse, misparing verdelings, en Bayesiaanse luglyn kurwes. Demografiese ontleding dui daarop dat al vyf die intergety slakke wat ondersoek is demografiese uitbreidings ervaar het wat terugdateer tot die einde van die Pleistoseen. Die sanderige strand direkte ontwikkelaar, B. rhodostoma, het die uitbreiding begin na die LGM (c. 15 Kya), terwyl vir die vier rotsagtige kusbewoners wat eiers oor 'n uitgebreide gebiede versprei (T. sarmaticus, O. sinensis, O. tigrina, en O. variegata) het die aanvang van die bevolkings uitbreiding saamgeval met die laaste galsiasie of dit voorafgegaan (c. 25, 60, 50, 40 Kya, onderskeidelik). In ooreenstemming met die onlangse reeks bevolkings uitbreidings, is die bevolking genetiese struktuur in alle spesies gekenmerk deur weinig differensiasie. Oxystele variegata was 'n uitsondering en het 'n ontwrigting van laat Pleistoceen oorsprong getoon tussen individue langs die weskus Namaqua Biostreek en dié in die suid kus Agulhas biostreek. Hierdie resultate voorsien sterk bewyse van die belangrike rol wat die Pleistoseen klimaatsveranderinge gespeel het in die vorming en verspreiding van biodiversiteit langs die Suid-Afrikaanse kus. Daarbenewens, geen vloei in alle spesies, behalwe O. tigrina, was merkwaardig asimmetries. Kaap Infanta en Port Elizabeth verteenwoordig moontlik die bron bevolkings. Met inagneming van die geringe bevolking genetiese struktuur en geenvloei patrone wat waargeneem is vir die meeste slak spesies wat bestudeer is, word dit aanbeveel dat T. sarmaticus, O. sinensis, O. tigrina en B. rhodostoma bestuur word as 'n panmiktiese bevolking, en dat die streek wat Kaap Infanta en Port Elizabeth insluit geprioritiseer moet word vir bewaring. Oxystele variegata was die enigste spesie wat duidelike bevolking struktuur getoon het en in hierdie geval, moet spesie spesifieke bewaringspogings aangewend word.

Laboratory bacterial populations provide ideal opportunities to experimentally test theories in ecology and evolutionary biology. I used a model laboratory microbial system, Pseudomonas fluorescens SBW25, to address an array of questions on the origin, maintenance, and functional role of biodiversity, and the evolution of biotic interactions. My thesis reports experiments with the following conclusions. (1) The extent of diversification in P. fluorescens populations is not affected by the presence of an interspecific competitor P. putida, although the early stage of the diversification in one environment (spatially homogeneous environment) could be speeded up by the competitor. (2) Niche and neutral mechanisms simultaneously contribute to the maintenance of phenotypic diversity in P. fluorescens populations; but the operation of niche processes does not lead to a positive effect of biodiversity on ecosystem functioning. (3) The competitive interactions among bacterial phenotypes are generally transitive, and competitive hierarchies inferred from pair-wise competition are fairly consistent to those from multi-species competition. (4) The niche complementarity and selection effects evaluated by random assembly biodiversity experiments can be used to predict the functional consequences of particular non-random species extinction scenarios. (5) P. fluorescens does not show an evolutionary trade-off in using several carbon substrates (glucose, galactose and trehalose), and evolution in environments containing these resources results in imperfect generalists; migration among populations may speed up fitness evolution of some generalists. (6) Biofilm formation at the air-broth interface by wrinkly spreader phenotypes in P. fluorescens is a cooperative behaviour which is costly to individuals but benefits the group; this behaviour could be exploited by smooth morph phenotypes. The cooperators and cheats in this system show reciprocal antagonistic coevolution in resistance and cheating performance.

Proposals for the internal relationships and classification of the bostrichoids are currently poorly supported, and almost all are based on morphology alone. This study improves upon on previous phylogenetic analyses of the group by including more taxa using the standard genes for many phylogenetic analyses. Cytochrome C oxidase subunit 1 (CO1), 28S small subunit rRNA, and 16S small subunit rRNA mitochondrial genes were sequenced or obtained from Genbank, then analyzed using parsimony and Bayesian analyses. Topologies differed depending on genes used. A three gene tree and a two gene (28S and CO1) tree both supported relationships in which a basal bostrichid clade was sister to Ptinidae s. s. + anobiids, with another bostrichid clade within the ptinids. Current bostrichid and anobiid subfamilies tested were not supported as monophyletic in any of the trees obtained. Additionally, five new species of spider beetles in the genus Meziomorphum Pic from South Africa are described including M. endrödyi, M. boroveci, and M. nama from the Richtersveld, M. bulla from south-central Namaqualand, and M. cederbergensis from the Cederberg. Genitalia are illustrated for the genus for the first time for six of the 10 species now known. A brief discussion of the evolution of generic morphology and biology as well as the relationships of the genus to other spider beetle groups are also provided. Finally, a revision of the genus Eutaphroptinus is presented. Eutaphroptinus pseudonatalensis is considered a synonym of Eutaphroptinus natalensis. New species records of E. natalensis are also provided, as well as illustrations of the genus.

Thesis (M.A.) - Carleton University, 2005. / Includes bibliographical references (p. 126-136). Also available in electronic format on the Internet.

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 196-218).

Thesis (M. Sc.)--University of Ottawa, 1997. / Includes bibliographical references (leaves 82-99).

This study explores two interlinked aspects of human-environment relationship—cash crop development and biodiversity conservation—by examining the situations of the Hmong people, the largest traditional pioneer swidden group in the Thai highlands. Cash crop adoption among the Hmong have occurred in two main ways. The first involves the adoption of low-input upland crops and a shift to high-input vegetable crops. This pattern is found in the Lower North and spread to the Upper North, particularly in Tak, Phrae, Nan, Payao and Chiang Rai. The adoption is closely linked to the development of roads into the uplands and the diffusion of maize cultivation in the lowlands. The second pattern is a direct shift from opium to high-input crops, particularly cabbage. Large scale cabbage growing began in the early 1980s as a response to the demand for off-season vegetables. The most important driving factors behind cash crop adoption were the government poppy eradication activities, the contacts between market agents and the Hmong and the increased accessibility of Hmong villages. Adoption was facilitated by favourable market prices at the initial period and by the Hmong clan network. Each type of cash crops has had its particular effects on the Hmong socio-economy. Cut-flowers bring small but regular income into a household while cabbages bring a lump sum, a few times a year. Cabbage production induces high level of truck ownership leading to increased mobility, rapid diffusion of innovations, changing cultural values and increased uses of lowland services (such as health care, schools, market, etc.). Flower production, on the other hand, allows women to take active parts in marketing. The study also found a type of movement not discussed in earlier literature, the temporary migration of households or parts of households to take advantage of successful cash crop cultivation in other villages for a period of 1–2 years. The examination of four cash crops: opium, maize, cabbage and carnations shows that the Hmong have gradually shifted from land extensive to land intensive cash crops. This move to economize on land is, however, recompensed by the need for high inputs in agriculture. The more land intensive the crop is, the more fertilizers and pesticides are used. Comparisons between crops on three variables: population-land ratio, income and pesticide used per unit area, suggest that cut-flowers may be a superior crop, if measures to reduce pesticide uses can be found. Cash crop adoption affect the relationships between the people and wildlife in three ways. First, the labour-intensive nature of cash crop production prevents farmers from spending as much time in the forest as in the past. Second, cash crops provide incomes which allow the people to obtain meat from the market and thus reducing the needs for wild meat. Third, cash crop economy orients people toward the lowland, resulting in weakening traditional knowledge about wildlife behaviours, hunting or trapping. Most Hmong view hunting as a leisure activity, and some, particular women, see it as a waste of time. Reduced hunting, however, has not lessen the pressure on wildlife as the population of all species are reportedly declining. Many Hmong villages have rules against hunting some species, particularly gibbons. This rule is respected by most people but not all. Since the people do not feel that their livelihood is greatly affected by the disappearance of wildlife, the direct relationships between economic improvement and conservation is not clearly apparent. / Graduate