Allopatric populations of Pseudocrenilabrus philander were found to differ in male breeding coloration. These colours are described and attention is drawn to the possibility that male coloration might prevent population hybridisation. Behaviour of the allopatric populations was studied in the laboratory. The execution of behaviour patterns of the various populations was found to be indistinguishable, and very similar to that of Haplochromis. Behaviour of P. philander was recorded in three morphologically different natural water bodies. Diurnal activities were found to follow a set rhythm. Though P. philander was shown to have adapted to a variety of habitats they retained their behavioural Components in an unchanged form. Field and laboratory observations are used to propose a behavioural mechanism for the natural regulation of population density. Although aggression between conspecific territorial Sarot herodon mossambicus habituated so that neighbours could live close to one another, it was found that P.philander are intolerant of their neighbours and are consequently forced apart. Though the execution of behaviour patterns was apparently identical for all populations of P. philander, field observations indicated that the frequency of performance differed. An experimental procedure was established to quantitatively compare the behaviour of various populations. As a result of comparative and choice chamber investigations, it is suggested that one of the four populations of P. philander would be unlikely to hybridise with the others if they were to become sympatric. These popUlations would be kept apart because of colour and behavioural differences. Differences of egg-size, fry-size, developmental and interbrood periods were also found, providing further evidence of incipient speciation. Evolutionary divergence of the allopatric populations of P. philander is discussed against a background of geological and geographical evidence. Consideration is given to the role of male coloration, ethological barriers and the importance of ethological differences to taxonomy. Behavioural evidence suggests that P. philander has closer affinities with the haplochromids than was initially realised. It is concluded that the clinal populations of P. philander should not be taxonomically separated, and it is argued that it would be premature to give the Kuruman population an elevated taxonomic status.

1. Twenty four species of the genus Sisyphus known in southern Africa are listed with their synonyms and their taxonomy is discussed. 2. A key to the adults of 23 of these species is given. 3. The known distribution of 23 species and seasonal occurrence of 19 species are illustrated and briefly discussed. 4. The general biology of the genus Sisyphus is discussed and the major behavioural and biological differences between the two subgenera Sisyphus and Neosisyphus are given. 5. The laboratory and field investigation into variations in behaviour and biology in eight species occurring in the Mkuzi Game Reserve, with regards to interspecific competition, is presented. 6. The known possible natural enemies of Sisyphus are mentioned and the extent of competition from other genera, based on field and laboratory observations, is outlined. 7. Summary tables of all data with a final tabulated evaluation of the suitability of species for introduction into Australia is given. 8. Nine species have been highly recommended for Australia. Six more species could be considered but most of these still need further investigation. The remaining nine species were found to be unsuitable for transfer to Australia.

Tamarix (Tamaricaceae) is from the Old World, but has become naturalized and invaded other parts of the world including South Africa. Tamarix usneoides is the only species native to southern Africa, but the exotic species T. aphylla, T. chinensis, T. parviflora and T. ramosissima have been reported to be present in South Africa and these Tamarix species are hypothesized to be hybridizing among themselves and with the indigenous T. usneoides. Among the exotic species, T. chinensis, T. ramosissima and their putative hybrids have become invasive. Tamarix usneoides is used in southern African mines for phytoremediation as it has the ability to hyper-accumulate sulphate and heavy metals from Acid Mine Drainage from Tailing Storage Facilities and excretes gypsum (CaSO4). Tamarix species are morphologically and ecologically similar, making them difficult to distinguish and hybridization adds to the taxonomic confusion. Identification of Tamarix species in South Africa is of great importance because of the invasive potential of T. chinensis, T. ramosissima and their putative hybrids, and also because of the potential usefulness of T. usneoides. This investigation aimed to identify populations of pure T. usneoides that can be cloned for cultivation for phytoremediation on the mines, and to reveal the geographic origin of the invasive species to facilitate a biological control programme. Nuclear (ITS) and plastid (trnS-trnG) DNA sequence data and the multilocus Amplified Fragment Length Polymorphisms (AFLPs) markers were used in this study to characterize southern African Tamarix species and their putative hybrids. Phylogenetic analyses and population genetic structure confirm the presence of three Tamarix species in South Africa (T. chinensis, T. ramosissima and T. usneoides) with admixed individuals (Tamarix hybrids). The indigenous T. usneoides is clearly genetically distant from the alien species T. chinensis and T. ramosissima. Although the exotic species remain largely unresolved in the phylogenies, they are distinctly separated through AFLP markers. The Tamarix infestation in South Africa is dominated by hybrids between T. chinensis and T. ramosissima, and the parent species match their counterparts from their places of origin in Asia. These places of origin in Asia can provide the source of potential biological control agents. Some remote populations, e.g. Witbank, Goodhouse and Henkries in the Northern Cape Province/South Africa at the border with Namibia, of pure breeding T. usneoides have been identified and these should be used as a source of genetic material that can be propagated for planting on the mines for phytoremediation programmes.

Background: Studies have reported that one of the outcomes of on-going social and demographic transition is breakdown in families’ structure. Thus the emergence of single mother families is an observed trend which is associated with poverty and negative child outcome. This study examines the levels and factors associated with single motherhood in Southern Africa. Data source and methods: This is a cross-sectional study of Demographic and Health Survey (DHS) data sets for three Southern African countries of study: Lesotho (DHS) 2009, Swaziland (DHS) 2006-2007 and, Zimbabwe (DHS) 2010-2011. A total sample of 5586 women aged 15-49 for Zimbabwe, 4063 for Swaziland and 2541 for Lesotho who are either currently married or not and have at least one dependent child prior to the survey was included in the study. Data analysis was done at three stages; univariate, bivariate and multivariate level. Multivariate logistic regression which yielded odds ratio was used to identify the socioeconomic and demographic correlates of single motherhood. Results: The findings showed that the level of single motherhood in Zimbabwe is 20% (1091), Lesotho 25% (1011) and Swaziland 41% (1041) with premarital childbearing as the main source of single motherhood in the region, while widowhood and divorce is relatively low. Comparing the three countries of study in terms of correlates of single motherhood, the evidence suggested that age of respondents and number of living children, are correlates of single motherhood while religion was found not to be associated with single motherhood in all the countries of study. Younger women were more likely to become single mothers compared to older women while women with more than 2 living children are less likely to be single mothers compared to those with 1 or 2 living children. Conclusion: This study concludes that single motherhood is high in southern Africa. The implication of the rapid spread of single motherhood both reflects and reinforces the declining significance of marriage as a family status and a context for bearing and raising children. Also it may have negative implications for children from single mother families and the mothers themselves.

Thesis (MScAgric (Agricultural Economics))--University of Stellenbosch, 2007. / Regional food security is considered one of the major challenges for the Southern African Development Community (SADC) countries. SADC is one of the regions in the world currently facing widespread transitory and chronic food insecurity (malnutrition), as well as persistent threats of acute food insecurity (famine). The objective of this thesis, therefore, was to investigate and assess the prevailing causes of food insecurity in Southern Africa. The research revealed that transitory and chronic food insecurity (malnutrition) in the SADC region exists due to the problems experienced with both the supply and demand sides of the food security equation. However, though SADC has made limited attempts to tackle the problem of food insecurity in the region, the Community did not appear to learn from the 1991/92 food insecurity crisis when it recurred in 2001/02. This study consequently recommends that further investigations take place into the primary data available in an attempt to address various issues relating to the causes of food insecurity in Southern Africa in order to ensure long-term food security. Such issues include the following: mobilising agriculture to increase food production rapidly enough to meet the needs of the growing population of the region; bridging the prevailing gap between the public actors, on the one side, and the private and informal actors, on the other, in order to deliver effective food security services to the needy in the region; the designing of well-targeted food pricing policies as an interim compromise between the social concerns relating to high and volatile food prices and long-term economic growth and food security in the region; and the identification of the role of women as food producers and agents of food security in the region. On the supply side, the main food availability problems in the region lie on the agricultural level. Low productivity and frequent disasters have been of a cyclic nature in SADC, leading to additional difficulties with supplies. Such difficulties have been compounded by the inadequate political support of the sector; a lack of investment therein; the instability of the world market; and an increasingly unfair trade environment. Other major dimensions of the problem include: the imposition of trade barriers, such as tariff, non-tariff and technical barriers, particularly the complex and confusing tariff structure imposed by the Southern African Customs Union (SACU) countries against other non-SACU SADC countries; the high cost of transport, especially in landlocked countries, which has come about as a result of the weakening of the capacity and efficiency of the transport system in the region, due to a lack of investment in, as well as the poor performance of, the transport sector. A lack of a diversified production structure in the SADC region was cited as the main obstacle to the successful trade integration and economic development of the region. Looking at the demand side, the main food access problems in the region consisted of a lack of food entitlement (poverty) due to the weak economic growth resulting from unsuccessful macroeconomic policies; a poor balance of payments situation; highly skewed patterns of income and wealth distribution, resulting from maladministration due to short-sighted past colonial policies; high levels of unemployment and land tenure insecurity; the failure of governance, both as regards a lack of accountability and opposition to democratisation; and financial mismanagement. Rapid population growth in the region resulted in an escalation in the demand for agricultural products, in particular foodstuffs, and the reduced availability of arable land. The widespread preponderance of Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) infection was complicating the task of fighting hunger and undermining any attempts to strengthen the livelihoods of the poor by depleting the adult agricultural labour potential in Southern Africa. A lack of financial resources and institutional capacity (in the form of policy gaps) were the main constraints to the implementation of successful poverty and food insecurity alleviation programmes in the region, as comprehensive government intervention aimed at maintaining food security in the region for most Southern Africans was unfeasible in the near future. The research was conducted using the qualitative method of literature study, which proved a useful descriptive and analytical framework for revealing significant causes of food insecurity prevailing both in individual, households and at national levels in the SADC region. The study focused mainly on the availability, and the ability to acquire, food, in an attempt to see how balance could be achieved between the supply and demand sides of the food security equation by means of relevant investigations. Documentary data were consulted in investigating the problem, in the light of the fact that publications, such as books, academic journals and documents, illustrate the problem most clearly. In the planning of policy interventions, food insecurity in Southern Africa appears open to improvement in the long term only if the actual income of households is increased, so that they can afford to obtain enough food. Such improvement can take place in two ways: Firstly, by giving the people who face transitory and chronic food insecurity the opportunity to earn enough to ensure that they can maintain an adequate food supply through domestic production, by improving agricultural yield, and hence ensuring food security, at household level, and secondly, by means of the facilitation of trade (in the form of food imports), by eliminating tariff, non-tariff and technical barriers, and investing in the development of the transport infrastructure in the SADC region.

M.Com. (Economics) / The main purpose of the study was to investigate the role of economic integration in the economic development of the member states of an envisaged economically integrated Southern African bloc, that would include South Africa. The study contends that economic development will be aided, if economic integration were implemented correctly. Economic integration will influence both the allocation and distribution elements of the involved countries' wealth. Since economic development is inextricably entwined with the distribution of wealth, economic integration would have to give special attention to its effect on the distribution of wealth between countries. The mainstream theory of economic integration, however, places much more emphasis on the allocation aspect of integration than the distribution aspect. This imbalance means that economic integration, implemented according to the guidelines of the mainstream theory, will be detrimental to the economic development of especially the less developed countries. The orthodox approach to economic integration should therefore be adapted to the circumstances of developing countries. A suitable economic integration approach should comprise two steps. The first step involves the identification of areas for profitable specialisation, and the second the formulation of an economic integration strategy within the framework of a dirigiste approach to economic development. Porter's theory of the competitive advantage of nations served as the foundation for the formulation of the approaches to both economic development and economic integration in Southern Africa. Industry segments in which profitable specialisation could take place, were identified for South Africa, Malawi, Zambia and Zimbabwe by means of Porter's statistical method, and afterwards classified in clusters. The development and integration approaches will be centred around the various identified clusters with competitive advantage.

One of the central tenets of much current development thinking in southern Africa is that market-oriented strategies and private sector involvement must be the basis for future economic growth. This has underpinned structural adjustment and economic policy reform policies in the region over the last decade or more. It also underlies the argument for encouraging external foreign direct investment (FDI) as a motor for growth. However growing evidence suggests that such a strategy has not paid off. Economic growth rates have been disappointing, private, and particularly foreign, investment has been limited, and employment in the formal sector has fallen dramatically.1 Structural adjustment and market liberalisation have clearly not delivered the developmental benefits claimed of them, and people's livelihood opportunities have, ft seems, declined over the same period and their levels of vulnerability have increased. The increasing recognition that the standard neo-liberal prescriptions were not having the expected benefits, especially for poor people, has resulted in some rethinking about how best to redirect the benefits of globalisation and economic reform towards the poor, and how to offset some of the losses. Thus ‘pro-poor growth strategies’, ‘making markets work for the poor’ and ‘growth for redistribution' have become well-worn slogans. However, the practical and policy measures required, whereby the benefits of an engagement with a globalised economy, investment by the private sector and liberalisation privatisation measures can result in poverty reduction, remain vague.A number of issues arise. For the sceptics, questions are raised about the degree to which the turn to a 'pro-poor' markets approach is simply rhetorical gloss, added to the discredited neo-liberal paradigm, or actually a genuinely new policy perspective in its own right. It is important to differentiate between broad economic policy reform objectives (which, with some nuances, remain largely in the standard neo-liberal form) and sectoral policies which contain explicitly pro-poor elements. While retaining the argument that market liberalisation and external investment are key, such policies may include some strategic elements of state- directed intervention which boost the access of the poor to new markets and investment opportunities. It is this stance, where the state intervenes to improve access and for particular groups of people, redressing to some extent the imbalances caused by the lack of level playing fields of existing markets, which potentially sets a pro-poor perspective apart.

Thesis (Ph. D.)--University of Chicago, Dept. of Germanic Studies, August 2001. / Includes bibliographical references. Also available on the Internet.

Thesis (diploma in librarianship)--University of the Witwatersrand.

Thesis (diploma in librarianship)--University of the Witwatersrand.