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A molecular genetic assessment of the population structure and variation in two inshore dolphin genera on the east coast of South Africa

  • Authors: Smith-Goodwin, Jacqueline Anne
  • Date: 1998
  • Subjects: Dolphins -- South Africa Variation (Biology) Dolphins -- Genetics Population genetics Bottlenose dolphin -- South Africa Sousa -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4007 , http://hdl.handle.net/10962/d1004067
  • Description: Coastal dolphins on the South African east coast are threatened by degradation and loss of habitat as a result of increasing coastal development, industrial effluent and agricultural runoff. In addition, dolphins off the coast of KwaZulu-Natal have, for more than four decades, been heavily exploited through unchecked incidental capture in shark nets set at 45 beaches. In light of the high rate of mortality and apparent depletion of both species, the persistence of bottlenose (Tursiops truncatus) and humpback (Sousa chinensis) dolphins in that region has been questioned. Genetic variation in south east African dolphin populations was determined as a means of assessing the fitness of the populations and their resilience to demographic disturbances. Furthermore, in order to determine the effects of continued mortality on the KwaZulu-Natal subpopulations, it was necessary to determine whether they are open or closed to immigration from the adjacent East Cape region, which represents a relatively unstressed region, characterised by a lack of shark nets and less intensive coastal activities. Genetic variation and differentiation in the maternal genome was assessed by determining the sequence of the first 400 bases of the mtDNA control region in bottlenose and humpback dolphins from KwaZulu-Natal and the East Cape. Nuclear variation and differentiation was estimated at six microsatellite loci and compared with earlier estimates determined from allozyme electrophoresis. Random amplified polymorphic DNA (RAPD) was assessed as a means of identifying population subdivisions and diagnostic population markers. Both bottlenose and humpback dolphins on the South African east coast are characterised by low nuclear and organellar genetic variation, consistent with a possible genetic bottleneck, the inferred date of which coincides with the onset of the last glacial period. Genetic variation in South African bottlenose dolphins was lower than that reported elsewhere for the species, while an intraspecific comparison supported lower genetic variation in South African humpback dolphins than in humpback dolphins sampled off Hong Kong. An analysis of molecular variance (AMOVA), performed on mtDNA haplotype frequency data indicated, for both species, significant genetic subdivision, concordant with geographic location. The data suggested female bottlenose dolphins demonstrate regional philopatry, displaying limited movement between KwaZulu-Natal and the East Cape. Female humpback dolphins tend towards strict local philopatry, with significant maternal differentiation evident both within and between regional subdivisions. Differentiation in microsatellite allele frequencies was also demonstrated between KwaZulu-Natal and the East Cape for both species, suggesting that the movement of male bottlenose and humpback dolphins may also be restricted. Nonetheless, considerably higher nuclear gene flow estimates suggested that males of both species represent the principal vectors of gene dispersal. The implications of historically low genetic variability and population subdivision in South African dolphins are important in view of the current rate of mortality in KwaZulu-Natal. The persistence of coastal dolphin populations relies on their ability to recover following a bottleneck event. Continued removal of demographically important age-sex classes such as occurs in shark nets, may not only further reduce the genetic variation, but would ultimately deplete dolphin populations in KwaZulu-Natal beyond a sustainable number, resulting in eventual local extinction. The differentiation of the two regions implies that, in the event of local extinction occurring, dolphins, particularly females, from adjacent regions will not readily re-colonise the area. This would result in fragmentation of the south east African populations and ensure reproductive isolation from neighbouring populations on the east African coast.
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  • Date Issued: 1998

The Marinkas Quellen Carbonatite Complex, southern Namibia: carbonatite magmatism with an uncontaminated depleted mantle signature in a continental setting

  • Authors: Smithies, Robert H , Marsh, Julian S
  • Date: 1998
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149736 , vital:38879 , https://doi.org/10.1016/S0009-2541(98)00029-1
  • Description: The Marinkas Quellen Carbonatite Complex, in southern Namibia, forms part of the ca. 490–550 Ma Kuboos-Bremen Igneous Province, a zone of alkaline igneous rocks that intrude the Mesoproterzoic to Paleoproterozoic Namaqualand Metamorphic Province and Neoproterozoic platform sediments. The carbonatite complex includes Ca-rich, Mg-rich and Fe-rich carbonatites as well as late ferrocarbonatite dykes that show extreme enrichments in Mn, REE and Th. Compared to most carbonatites, those at Marinkas Quellen are generally depleted in most trace elements, particularly Ba and the LREE.
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  • Date Issued: 1998

Ikatara

Moncoko simbabile

A case study of the implementation of the communicative approach to English second language progress testing in one secondary school in the Alexandria Circuit of the Eastern Cape Department of Education

  • Authors: Ssemakalu, John
  • Date: 1998
  • Subjects: Communicative competence , Communicative competence in children , English language -- Study and teaching (Secondary) -- Foreign speakers -- South Africa -- Eastern Cape , Language and languages -- Study and teaching (Secondary) -- Foreign speakers -- South Africa -- Eastern Cape , Second language acquisition -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2362 , http://hdl.handle.net/10962/d1002645 , Communicative competence , Communicative competence in children , English language -- Study and teaching (Secondary) -- Foreign speakers -- South Africa -- Eastern Cape , Language and languages -- Study and teaching (Secondary) -- Foreign speakers -- South Africa -- Eastern Cape , Second language acquisition -- South Africa -- Eastern Cape
  • Description: This study explores the implementation of the communicative approach (CA) to English second language progress testing in an African secondary school which falls under the Eastern Cape Department of Education. The goal of the research is to establish how teachers access, conceptualise, and apply the CA to language testing in their specific working conditions. The report of the findings of the research reveals that teachers' understanding of the CA to testing differs from that of the linguists, curriculum designers, innovators, and syllabus writers. This is caused by a combination of factors including teachers' poor working conditions, the lack of focused pre-service training and effective in-service structures for their empowennent as the agents of innovation, coupled with the poor circulation and a lack of clarity in official documents on the CA to language testing. These constraints made it impossible for teachers to implement the CA to language testing. In order to carry on with their work, however, teachers developed coping strategies by drawing, probably unconsciously, on a mixture of structuralist, sociolinguistic-psycholinguistic, communicative and any other testing practices they may have acquired during their years of service. Although based only on one school, the findings of this study indicate that for fundamental innovations such as the CA to take root, there is a need for the adoption of more dedicated, reflective implementation strategies involving proper planning and monitoring, as well as evaluation and re-evaluation of the entire process. This necessarily slow process must go hand-in-hand with a dedicated pre-service and in-service empowerment program based on consultative communication between innovator and agent; and a persuasive education/re-education approach which will encourage teachers to change their entrenched practices.
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  • Date Issued: 1998

Women's experience of abortion : a qualitative study

  • Authors: Taylor, Gaye Lesley
  • Date: 1998
  • Subjects: Abortion , Abortion -- South Africa , Women -- Counseling of
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:708 , http://hdl.handle.net/10962/d1006522 , Abortion , Abortion -- South Africa , Women -- Counseling of
  • Description: Abortion is an emotive topic that always raises strong feelings. The purpose of this study, however, is not to focus on the religious, political or moral questions surrounding abortion. Abortion is a reality and in South Africa, where it has only recently become legal, there is a need to have an understanding of the effects on women in order to provide counselling services. There is also a need to provide services for the many women who have had illegal terminations in the past. This study reviewed the most recent literature on the subject and the researcher takes the view that although the scientific literature states there is little long term psychological effect of abortion, the non-positivist literature which records women's experiences tells another story. Some of the problems with the scientific literature is that psychological effects are not defined and there may be political motivation for the study, ie. an attempt is made to prove that the health costs are not high for abortion because there is little long term effect. The researcher, however, feels this does a disservice to women who have had abortions because there is a failure to provide counselling services. Some members of the feminist movement also deserve criticism because in their haste to give women their rights they fail to allow a woman to thoroughly explore her options beforehand and to provide support services afterwards. The researcher, however, also identified a new theme in the literature which has been called a maturing of the feminist viewpoint that along with the right to abortion, women also have a right to the mixed feelings that go with making, what is for many, a very painful decision. There is a recognition that abortion is about loss and thus there is a corresponding need to acknowledge women's need to mourn and to provide services. The study does not include the experience of women who seek abortions for reasons of poverty. It also excludes the experience of women who have abortions as a result of rape, incest or harm to the foetus. It is a qualitative study and a non-probability sampling technique which comprised snowball and purposive methods was used to identify respondents. In-depth semi-structured interviews using a broad theme of questions were conducted with five respondents. The women were asked to tell the stories of their abortions: their and their partner's feelings before and after, how they decided and the actual experience. They were also asked to identify counselling requirements, what they found helpful and what would have helped. The literature and the findings support the researcher's view that women who find themselves with an unexpected pregnancy need an opportunity to objectively consider all their options, namely keeping the baby, adoption or abortion, and to have an objective counsellor assist them in vigorously considering these. If they decide on a termination they need to be given as much information as possible about the procedure and about how they are likely to feel. Afterwards counselling should be made available and women should be encouraged to use the service. They need to be assisted to explore all ways of coming to terms with it such as through dream work, dialogueing with the unborn child through a letter and for those with religious beliefs seeking absolution from the church. There is a great need for a Christian and other religious ministry in this regard. Self-help therapies such as support groups can also be helpful
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  • Date Issued: 1998

Atterrissage

  • Authors: TP Audiorama Orchestra (performers) , Showbiz
  • Date: 1998
  • Subjects: Popular music , Popular music--Africa, West , Africa Cote d'Ivoire Abidjan f-iv
  • Language: French
  • Type: sound recordings , field recordings , sound recording-musical
  • Identifier: http://hdl.handle.net/10962/129611 , vital:36313 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC30-08
  • Description: Ako music from Cote d'Ivoire performed by the TP Audiorama Orchestra, the first orchestra to develp this genre of Ivorian music
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  • Date Issued: 1998

Paris 95

  • Authors: TP Audiorama Orchestra (performers) , Showbiz
  • Date: 1998
  • Subjects: Popular music , Popular music--Africa, West , Africa Cote d'Ivoire Abidjan f-iv
  • Language: French
  • Type: sound recordings , field recordings , sound recording-musical
  • Identifier: http://hdl.handle.net/10962/129596 , vital:36310 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC30-05
  • Description: Ako music from Cote d'Ivoire performed by the TP Audiorama Orchestra, the first orchestra to develp this genre of Ivorian music
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  • Date Issued: 1998

Wui

  • Authors: TP Audiorama Orchestra (performers) , Showbiz
  • Date: 1998
  • Subjects: Popular music , Popular music--Africa, West , Africa Cote d'Ivoire Abidjan f-iv
  • Language: French
  • Type: sound recordings , field recordings , sound recording-musical
  • Identifier: http://hdl.handle.net/10962/129601 , vital:36311 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC30-06
  • Description: Ako music from Cote d'Ivoire performed by the TP Audiorama Orchestra, the first orchestra to develp this genre of Ivorian music
  • Full Text: false
  • Date Issued: 1998

Mariage

  • Authors: TP Audiorama Orchestra (performers) , Showbiz
  • Date: 1998
  • Subjects: Popular music , Popular music--Africa, West , Africa Cote d'Ivoire Abidjan f-iv
  • Language: French
  • Type: sound recordings , field recordings , sound recording-musical
  • Identifier: http://hdl.handle.net/10962/129569 , vital:36307 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC30-02
  • Description: Ako music from Cote d'Ivoire performed by the TP Audiorama Orchestra, the first orchestra to develp this genre of Ivorian music
  • Full Text: false
  • Date Issued: 1998

A Pi Cheche

  • Authors: TP Audiorama Orchestra (performers) , Showbiz
  • Date: 1998
  • Subjects: Popular music , Popular music--Africa, West , Africa Cote d'Ivoire Abidjan f-iv
  • Language: French
  • Type: sound recordings , field recordings , sound recording-musical
  • Identifier: http://hdl.handle.net/10962/129578 , vital:36308 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC30-03
  • Description: Ako music from Cote d'Ivoire performed by the TP Audiorama Orchestra, the first orchestra to develp this genre of Ivorian music
  • Full Text: false
  • Date Issued: 1998

Ahoussa Kabun

  • Authors: TP Audiorama Orchestra (performers) , Showbiz
  • Date: 1998
  • Subjects: Popular music , Popular music--Africa, West , Africa Cote d'Ivoire Abidjan f-iv
  • Language: French
  • Type: sound recordings , field recordings , sound recording-musical
  • Identifier: http://hdl.handle.net/10962/129583 , vital:36309 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC30-04
  • Description: Ako music from Cote d'Ivoire performed by the TP Audiorama Orchestra, the first orchestra to develp this genre of Ivorian music
  • Full Text: false
  • Date Issued: 1998

Assi Olivier

  • Authors: TP Audiorama Orchestra (performers) , Showbiz
  • Date: 1998
  • Subjects: Popular music , Popular music--Africa, West , Africa Cote d'Ivoire Abidjan f-iv
  • Language: French
  • Type: sound recordings , field recordings , sound recording-musical
  • Identifier: http://hdl.handle.net/10962/129606 , vital:36312 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC30-07
  • Description: Ako music from Cote d'Ivoire performed by the TP Audiorama Orchestra, the first orchestra to develp this genre of Ivorian music
  • Full Text: false
  • Date Issued: 1998

The invertebrates of temporary rivers in the Eastern Cape, South Africa

  • Authors: Uys, Amanda Cloete
  • Date: 1998
  • Subjects: Rivers -- South Africa -- Eastern Cape Stream ecology -- South Africa -- Eastern Cape Freshwater invertebrates -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5628 , http://hdl.handle.net/10962/d1004908
  • Description: Temporary rivers in dryland regions are subject to highly variable and unpredictable rainfall and flow, and are considered unstable systems relative to perennial rivers of temperate zones. Little is known of the ecology of South Africa's temporary rivers, despite their abundance. The research presented focusses on the aquatic invertebrates inhabiting intermittently-flowing rivers in the 'arid corridor' of the Eastern Cape, South Africa. The major aims of the work were: to investigate which invertebrates inhabit these rivers, how the fauna is affected by environmental variability at various spatial and temporal scales, whether or not a characteristic fauna can be associated with these rivers or the hydrological phases which characterise them, and to establish to what extent faunal overlap occurs between different temporary rivers and between natural and modified temporary and perennial rivers. Research results indicate that the fauna of the Eastern Cape temporary rivers shows little structure at the scales of investigation, and that communities are generally non-equilibrial in character. The major forces shaping the biota are considered to be physical rather than biological, and the most important of these are: present and antecedent hydrological conditions and their duration; time of year; and biotope character, extent and heterogeneity. Three groups of fauna were identified as inhabitants of the temporary rivers: 'residents', 'facultative taxa' and 'opportunist colonists'. Taxa were tentatively allocated to these groups. Faunal resemblance was fairly high in Eastern Cape temporary rivers at the level of family, but not at more detailed taxonomic levels. A comparison between faunas of temporary and perennial rivers in different regions of South Africa illustrated the influence of geographical location on diversity. Within regions, however, there was no indication that perennial rivers were more diverse than intermittent rivers. The relatively high diversities in temporary rivers in this study are attributed at least in part to the heterogeneity in surface water conditions over time. A conceptual framework envisioning a continuum between perennial and temporary rivers is proposed as a basis for ongoing research into these rivers. A supporting terminology for the range of river flow types in South Africa is presented.
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  • Date Issued: 1998

Improvement of fertility and hatchability of artificially incubated ostrich eggs in the little Karoo

  • Authors: Van Schalkwyk, Salmon Jacobus
  • Date: 1998
  • Subjects: Ostrich farming -- South Africa , Eggs -- Hatchability , Eggs -- Incubation
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5713 , http://hdl.handle.net/10962/d1005399
  • Description: Ostriches are an important commercial species in South Africa and are becoming increasingly so in other parts of the world. Fertility and hatchability of artificially incubated ostrich eggs, however, is generally regarded as low compared to other poultry species and to ostriches in the wild. Investigation into specific farming practices at present indicated scope for an overall improvement in productivity through a sound breeding strategy. This thesis investigated factors that affect egg production, fertility, and hatchability of artificially incubated eggs in the Little Karoo region of South Africa. Specific breeding pair combinations accounted for the major variations in egg weight, hatchability, chick production and offspring weight at slaughter age. An appreciable proportion of variation in reproductive traits was attributable to the repeatable nature of breeding pair performance from year to year, even from first breeding attempts, suggesting that selection of good breeding stock can be made from an early age. Artificially incubated eggs showed improved hatchability when eggs were collected two to three hours after lay rather than the following morning. Storing position of eggs did not significantly effect hatchability when eggs were stored for a maximum of one week. The critical zero temperature for ostrich eggs, below which no embryonical development takes place, was found to be ± 25°C and cooling eggs to temperatures below 20°C for complete cessation of embryonic development during storage resulted in better hatchabilities compared to eggs stored at 25°C room temperature. Hatchability decreased when incubator temperatures were raised from 36 to 37.3°C. Large temperature fluctuations and gradients, which encompass detrimental temperatures, persist within forced draught wooden incubators of the type most commonly in use in the Little Karoo region. The highest temperatures occurred at the top of these incubators and will consequently have a negative impact on hatchability. The ontogeny of ostrich egg metabolism showed an exponential increase during the first 70% of incubation followed by a decline to 75% of the peak value between days 31 and 38 of incubation. From peak levels of embryonic development it was calculated that single stage incubators needs an airflow of 54.4 1/egg.hour to maintain oxygen levels just below 21% and carbon dioxide levels below 0.5%. Lower embryonic mortalities were observed when eggs were turned twenty-four times/day in an electronic incubator compared to hand turning twice a day. Eggs rotated through increasing angles between 60 and 90° resulted in a linear improvement in hatchability. In incubators where turning angles were fixed at 60°, lower hatchabilities were overcome by incubating eggs for 2 - 3 weeks in a horizontal position before placing them vertically. No specific farming practice could be singled out as the main cause of low fertility or hatchability but rather a combination of certain practices applied wrongly.
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  • Date Issued: 1998

Group problem solving among community activists in a South African setting: an everyday cognition approach

  • Authors: Van Vlaenderen, Hilde
  • Date: 1998
  • Subjects: Group problem solving Group problem solving -- South Africa Cross-cultural studies -- Methodology Cognition Cross-cultural studies Cognition -- Research
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3080 , http://hdl.handle.net/10962/d1002589
  • Description: The study focuses on the everyday problem solving processes of a group of community activists in a rural setting in the Eastern Cape Province of South Africa. It aims to uncover: first, the local knowledge of the participants of the study with reference to the concepts problem and problem solving; second, the participants' group problem solving procedure; and third, the dialectical interrelation between the participants' knowledge and practice with reference to everyday group problem solving. It is contended that the mainstream cognitive approach and the cross-cultural tradition are inappropriate for the study of everyday cognitive processes. A ‘situated cognition’ approach, based on the notions of activity and cultural mediation, is proposed as a theoretical framework for the study. The ontological and epistemological assumptions underpinning the empirical study were derived from a scientific realist and a hermeneutical paradigm. Data for the inquiry into the local knowledge of the participants was collected through individual interviews. The data was interpreted, using the grounded theory techniques of constant comparison, coding and compiling theoretical diagrams. Data for the inquiry into the participants' group problem solving practice consisted of video-taped group problem solving processes. This data was analysed, using a multi layered process of progressively deeper interpretation, employing a reading guide technique. Analysis of the research data revealed that the participants perceived a problem as an impediment to satisfactory participation in society. Problem solving was considered as an emotive, cognitive and inter-active process, involving particular role players. This process had a certain structure, involved attitudes and actions and relied on particular resources. Successful problem solving was perceived to result in restoration of social equilibrium. The group problem solving procedure used by the participants consisted of a process of developing a common understanding and group consensus. The strategies employed in the process, the roles played by the participants, the rules adhered to by the participants and the structure underlying the process were all congruent with these aims. There was a mutually reinforcing interrelation between knowledge and practice with reference to the participants’ problem solving.
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  • Date Issued: 1998

Conservatism and change: the refashioning of gender relations from 1870 to 1914: a case study of East London

  • Authors: Vernon, Gillian Noël
  • Date: 1998
  • Subjects: Women -- South Africa -- East London , Women -- South Africa -- Social conditions , Women's rights -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2567 , http://hdl.handle.net/10962/d1002420 , Women -- South Africa -- East London , Women -- South Africa -- Social conditions , Women's rights -- South Africa
  • Description: This is a case study of East London from 1870 to 1914 with gender as the critical analytical category. The focus is on change in the structure of gender relations, evaluated in terms of the recognition of the rights of women and their status in society and women of all race groups are dealt with. A feature of the source material has been the use made of oral history where interviews were conducted with the descendants of women who lived during the study period. There were many indirect factors which had a retrogressive influence on progressive change in the rights and position of women. The initial small size of the population and unbalanced gender ratios, the few natural resources, a small and limited port and periodic unpredictable natural disasters gave rise to a 'boom and burst' economy with very little industry. The result was that initially the women were very conservative and unwilling to make social changes. The military occupation and the outbreak of hostilities in the late 1870s affected social and racial attitudes detrimentally. The entrenched patriarchal system, under which both black and white women lived, and the legal controls, particularly in the marital situation, reinforced the subordination of women, making the system difficult to break. Further conservative forces were at work with the European class system being well entrenched, with most women working for upward mobility, gentrification and respectability. Wealth was critical in determining status and those women from the working class, who had achieved some degree of wealth and status, were not prepared to challenge the system. Religion was important for nearly all white women and converted black women, but was a retarding influence in the growth of feminist consciousness. Little progress was made in improving the condition of women who transgressed the law, the non-respectable women, and ethnicity made no difference. Progress was made in gender relations for women in some fields. The reduction in family size and the improvement in health, gave women more time and energy for public affairs. Participation in sport helped women discard the image of being weak and frail and also improved health. Educational opportunities allowed some to get tertiary training and obtain proper qualifications to earn a living for themselves. Xhosa women who came into the town, made a major break with traditional society and many became independent. The major impetus for change came through women's associations, where women actively worked together and achieved some positive results. Middle class white women could earn an independent living without losing respectability, although it was accepted that women should give up paid employment on marriage. Black women broke traditional ties and many urban women became independent. Conditions for working class and non-respectable women changed very little. A deduction is that many women, both white and black, had sympathy for one another and they created a fund of goodwill on both sides of the colour line.
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  • Date Issued: 1998

Interaction of nitric oxide with cobalt (II) phthalocyanine

  • Authors: Vilakazi, Sibulelo L , Nyokong, Tebello
  • Date: 1998
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/293579 , vital:57100 , xlink:href="https://doi.org/10.1016/S0277-5387(98)00244-7"
  • Description: The coordination of nitric oxide (NO) to cobalt(II) phthalocyanine (CoPc) in dimethyl sulphoxide (DMSO) has been studied. CoPc coordinates with NO in a 1:1 ratio, forming a CoPc(NO) species. The IR band observed at 1680 cm−1 is assigned to the coordinated NO. In the presence of excess NO, pseudo first order kinetics were followed. The observed rate constant, kf, was determined to be 15.0±0.3 dm−3 mol−1 s−1 and the equilibrium constant was K=5.4±0.4×104dm3 mol−1. Solution or adsorbed CoPc catalyses the reduction of NO. The products of reduction include NH3 and NH2OH.
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  • Date Issued: 1998

Aspects of the biology of the doublesash butterflyfish, Chaetodon marleyi (Pisces: Chaetodontidae)

  • Authors: Vine, Niall Gordon
  • Date: 1998
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:21103 , http://hdl.handle.net/10962/6396
  • Description: The doublesash butterflyfish, Chaetodon marleyi, indigenous to South Africa, is popular amongst marine aquarists. To provide a basis for the management of the species and assess its suitability for aquaculture, aspects of its biology were investigated. Specimens were collected between February 1996 and November 1997 from localities along the eastern Cape coastline of South Africa and from specimens in the RUSI fish collection. The dentition of C.marleyi is typical of non-coraline, benthic invertebrate feeding chaetodontids. The teeth are long, inwardly hooked and spatulate which allow easy grasping and manipulation of the prey. Stomach content analysis showed that the species fed predominantly on the tentacles of terebellid polychaetes with other polychaetes, crustaceans, hydro ids and ascideans contributing to the remainder of the diet. Juveniles had a larger volume of terebellid tentacles compared to adults which preyed more upon other polychaetes. The proximate composition (64.25% protein, 4.76% fat, 4.84% carbohydrate and 24.3 kJ/g total energy content) of the terebellid tentacles was determined suggesting a high energetic requirement of the fish or maximisation of feeding profit rates.
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  • Date Issued: 1998

Genre analysis and the teaching of academic literacy: a case study of an academic discipline in the social sciences

  • Authors: Vorwerk, Shane Paul
  • Date: 1998
  • Subjects: Lectures and lecturing , Lecture method in teaching , Language and culture , Discourse analysis , Language and culture -- South Africa , English language -- Discourse analysis , Intercultural communication -- South Africa , English language -- Study and teaching -- South Africa -- Foreign speakers
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2365 , http://hdl.handle.net/10962/d1002648 , Lectures and lecturing , Lecture method in teaching , Language and culture , Discourse analysis , Language and culture -- South Africa , English language -- Discourse analysis , Intercultural communication -- South Africa , English language -- Study and teaching -- South Africa -- Foreign speakers
  • Description: Students in tertiary educational institutions in South Africa come from many different backgrounds and have varied educational experiences. Some students, especially those from non-English speaking backgrounds, may encounter linguistic difficulties with various academic tasks. In order for students to be successful at university, they must become academically literate. That is, they must master all the reading, writing, listening and comprehension tasks required by the disciplines in which they are studying. One such task is presented by the academic lecture which is an integral part of any course of study. Linguistically, the academic lecture can be seen as a particular genre with unique characteristics. This study investigated some linguistic characteristics of academic lectures. The discipline of Political Science, as a Social Science, was chosen because there is little research that has been done on language in the Social Sciences. The Political Science sub-disciplines of Political Philosophy, South African Politics, and International Relations were used in this research. First year lectures were recorded from each of these three sub-disciplines. The linguistic characteristics of lectures were analysed using techniques drawn from Systemic Functional linguistic theory. The analysis concentrated on the aspects mode and field as they were realised in the lectures. In addition, higher level generic structure was also analysed. The insights gained from the analysis were validated through interviews with the lecturers who gave the lectures. The aim of this research was to develop a linguistic characterisation of the lecture genre as it occurs in the three sub-disciplines of Political Science. The results of this research suggest that although there is a unified academic lecture genre, there is variation according to sub-discipline. The implications of this variation are discussed with reference to their relevance to teaching academic literacy.
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  • Date Issued: 1998
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