The petrogenesis of the Kirwan Basalts of Dronning Maud Land, Antarctica
- Harris, Chris, Marsh, Julian S, Duncan, Andrew R, Erlank, Anthony J
- Authors: Harris, Chris , Marsh, Julian S , Duncan, Andrew R , Erlank, Anthony J
- Date: 1990
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145472 , vital:38441 , https://doi.org/10.1093/petrology/31.2.341
- Description: The 420 m thick sequence of Kirwan basalt crops out along the southernmost 50 km of the Kirwanveggen Escarpment (74°S, 6°W). There is little variation in major element chemistry of these basalts (SiO2 49·3–51·6 wt.%; MgO 5·1–6·6 wt.%), but the concentrations of certain incompatible elements (e.g., Zr) vary by factors of approximately two or more.
- Full Text: false
- Date Issued: 1990
- Authors: Harris, Chris , Marsh, Julian S , Duncan, Andrew R , Erlank, Anthony J
- Date: 1990
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145472 , vital:38441 , https://doi.org/10.1093/petrology/31.2.341
- Description: The 420 m thick sequence of Kirwan basalt crops out along the southernmost 50 km of the Kirwanveggen Escarpment (74°S, 6°W). There is little variation in major element chemistry of these basalts (SiO2 49·3–51·6 wt.%; MgO 5·1–6·6 wt.%), but the concentrations of certain incompatible elements (e.g., Zr) vary by factors of approximately two or more.
- Full Text: false
- Date Issued: 1990
The pursuit of poetry : a defence
- Authors: Gouws, John S
- Date: 1990
- Subjects: Poetry
- Language: English
- Type: Text
- Identifier: vital:632 , http://hdl.handle.net/10962/d1020701
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1990
- Authors: Gouws, John S
- Date: 1990
- Subjects: Poetry
- Language: English
- Type: Text
- Identifier: vital:632 , http://hdl.handle.net/10962/d1020701
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1990
The rise of the French organ symphony with special reference to the works of Alexandre Guilmant and Charles-Marie Widor
- Authors: Johnson, Bruce Richard
- Date: 1990
- Subjects: Guilmant, Alexandre, 1837-1911 Widor, Charles-Marie, 1844-1937 Organ music -- History and criticism
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2643 , http://hdl.handle.net/10962/d1002308
- Description: This thesis on the Rise of the French Organ Symphony refers especially to the relevant works of Alexandre Guilmant and Charles-Marie Widor. It commences with a survey of the historical background, dealing with the development of French organ music from the 16th to 19th Century and the development of organ building in France from the 17th to 19th Century. It then proceeds to descriptions of the organs of St Clotilde, La Trinité and St Sulpice Churches in Paris, which are followed by biographical profiles of Cesar Franck, Alexandre Guilmant and Charles-Marie Widor, respectively. The major part of the thesis is devoted to a detailed analysis of the organ sonatas of Guilmant and the organ symphonies of Widor, which are discussed from the point of their cyclic outline and aspects of form and of style. The final chapter summarises the major findings of the analytical research and evaluates by comparative method, the merits and achievements of the two composers. In addition, Appendices are attached, providing specifications of various French organs and pictorial material relevant to the thesis. A separate cassette tape features characteristic sounds of Cavailie-Coll organs.
- Full Text:
- Date Issued: 1990
- Authors: Johnson, Bruce Richard
- Date: 1990
- Subjects: Guilmant, Alexandre, 1837-1911 Widor, Charles-Marie, 1844-1937 Organ music -- History and criticism
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2643 , http://hdl.handle.net/10962/d1002308
- Description: This thesis on the Rise of the French Organ Symphony refers especially to the relevant works of Alexandre Guilmant and Charles-Marie Widor. It commences with a survey of the historical background, dealing with the development of French organ music from the 16th to 19th Century and the development of organ building in France from the 17th to 19th Century. It then proceeds to descriptions of the organs of St Clotilde, La Trinité and St Sulpice Churches in Paris, which are followed by biographical profiles of Cesar Franck, Alexandre Guilmant and Charles-Marie Widor, respectively. The major part of the thesis is devoted to a detailed analysis of the organ sonatas of Guilmant and the organ symphonies of Widor, which are discussed from the point of their cyclic outline and aspects of form and of style. The final chapter summarises the major findings of the analytical research and evaluates by comparative method, the merits and achievements of the two composers. In addition, Appendices are attached, providing specifications of various French organs and pictorial material relevant to the thesis. A separate cassette tape features characteristic sounds of Cavailie-Coll organs.
- Full Text:
- Date Issued: 1990
The role of the marriage counsellor in a Xhosa community: an exploratory-descriptive study
- Authors: Phorie, Constancia Lineo
- Date: 1990
- Subjects: Marriage counselling -- South Africa Xhosa (African people) -- Marriage customs and rites Marriage customs Family
- Language: English
- Type: text , Thesis , Masters , MSocSc
- Identifier: vital:686 , http://hdl.handle.net/10962/d1002011
- Description: The focus of this study is on the role the marriage counsellor should play in the Black community. This role is being placed in sharp perspective as a result of social change affecting the Black family. Problem-solving, including marriage counselling has traditionally been done by the extended family. This role of the family as a natural support system has been weakened by factors such as urbanization and Westernisation. This has prompted Black couples experiencing in particular marriage problems to make use of professional marriage counselling services from specialised and other welfare agencies. A major problem in the rendering of professional counselling services is that they are to a great extent based on Western civilization as far as basic philosophy and underlying assumptions are concerned. Thus intervention modalities used for marital problems in the Black community do not address the real needs of the people. The main objective of this study was to investigate how marriage counselling services are perceived in the Black community. It is expected that research findings would assist the helping professions make the necessary adjustments to make marriage counselling approaches more relevant to problems experienced in married life in the Black community. The study revealed that the family in the Black community is still regarded as the main problem-solver although people do go beyond the family for assistance. The nuclear family has also started to emerge in the Black community and bonds to the bigger family systems are beginning to loosen. The research findings indicated clearly that there is a need for professional marriage counselling and that services of this nature should be extended further into the Black community. A problem in this regard however is that the community will have to be educated to use these services
- Full Text:
- Date Issued: 1990
- Authors: Phorie, Constancia Lineo
- Date: 1990
- Subjects: Marriage counselling -- South Africa Xhosa (African people) -- Marriage customs and rites Marriage customs Family
- Language: English
- Type: text , Thesis , Masters , MSocSc
- Identifier: vital:686 , http://hdl.handle.net/10962/d1002011
- Description: The focus of this study is on the role the marriage counsellor should play in the Black community. This role is being placed in sharp perspective as a result of social change affecting the Black family. Problem-solving, including marriage counselling has traditionally been done by the extended family. This role of the family as a natural support system has been weakened by factors such as urbanization and Westernisation. This has prompted Black couples experiencing in particular marriage problems to make use of professional marriage counselling services from specialised and other welfare agencies. A major problem in the rendering of professional counselling services is that they are to a great extent based on Western civilization as far as basic philosophy and underlying assumptions are concerned. Thus intervention modalities used for marital problems in the Black community do not address the real needs of the people. The main objective of this study was to investigate how marriage counselling services are perceived in the Black community. It is expected that research findings would assist the helping professions make the necessary adjustments to make marriage counselling approaches more relevant to problems experienced in married life in the Black community. The study revealed that the family in the Black community is still regarded as the main problem-solver although people do go beyond the family for assistance. The nuclear family has also started to emerge in the Black community and bonds to the bigger family systems are beginning to loosen. The research findings indicated clearly that there is a need for professional marriage counselling and that services of this nature should be extended further into the Black community. A problem in this regard however is that the community will have to be educated to use these services
- Full Text:
- Date Issued: 1990
The silent patient: a consideration of Gendlin's recommendations in the treatment of a silent adolescent
- Authors: Le Roux, J D
- Date: 1990
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193054 , vital:45294
- Description: This study comprises a dialogue between Gendlin's recommendations on the treatment of the silent patient and case-material taken from 39 sessions of psychodynamic psychotherapy with a 16 year old adolescent. The most characteristic feature of the therapy with this young person, was her pattern of silence and unresponsiveness. The aim of this study is to ascertain the usefulness of Gendlin's recommendations in the therapy of this category of patient. The dialogue between the suggested recommendations and the case- material served to illustrate the point that Gendlin's recommendations are of great value in the treatment of the silent adolescent. The value of these recommendations lie in their ability to comment meaningfully on the process of therapy with the silent patient by providing not only skills and techniques, but also a conceptual framework within which to contextualize the therapy. The recommendations were also found to be sensitive to some of the key issues of relevance to adolescence as a developmental phase. The case-study method was deemed an appropriate structure within which to conduct this examination. , Thesis (MA) -- Faculty of Humanities, Psychology, 1990
- Full Text:
- Date Issued: 1990
- Authors: Le Roux, J D
- Date: 1990
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193054 , vital:45294
- Description: This study comprises a dialogue between Gendlin's recommendations on the treatment of the silent patient and case-material taken from 39 sessions of psychodynamic psychotherapy with a 16 year old adolescent. The most characteristic feature of the therapy with this young person, was her pattern of silence and unresponsiveness. The aim of this study is to ascertain the usefulness of Gendlin's recommendations in the therapy of this category of patient. The dialogue between the suggested recommendations and the case- material served to illustrate the point that Gendlin's recommendations are of great value in the treatment of the silent adolescent. The value of these recommendations lie in their ability to comment meaningfully on the process of therapy with the silent patient by providing not only skills and techniques, but also a conceptual framework within which to contextualize the therapy. The recommendations were also found to be sensitive to some of the key issues of relevance to adolescence as a developmental phase. The case-study method was deemed an appropriate structure within which to conduct this examination. , Thesis (MA) -- Faculty of Humanities, Psychology, 1990
- Full Text:
- Date Issued: 1990
The South African sugar industry
- Authors: Lewis, Colin A
- Date: 1990
- Language: English
- Type: Article
- Identifier: vital:6695 , http://hdl.handle.net/10962/d1006730
- Description: The sugar industry was established in Natal in the mid-nineteenth century. By the 1980s, South Africa produced c. 2 million metric tons of sugar per annum and, directly or indirectly, the industry supported almost one million people. Exports, which amounted for almost half the sugar produced in the 1970s, declined during the 1980s and low prices together with American and Canadian sanctions have forced the industry to consider alternative uses for sugar cane.
- Full Text: false
- Date Issued: 1990
- Authors: Lewis, Colin A
- Date: 1990
- Language: English
- Type: Article
- Identifier: vital:6695 , http://hdl.handle.net/10962/d1006730
- Description: The sugar industry was established in Natal in the mid-nineteenth century. By the 1980s, South Africa produced c. 2 million metric tons of sugar per annum and, directly or indirectly, the industry supported almost one million people. Exports, which amounted for almost half the sugar produced in the 1970s, declined during the 1980s and low prices together with American and Canadian sanctions have forced the industry to consider alternative uses for sugar cane.
- Full Text: false
- Date Issued: 1990
The Southern African Development Coordination Conference (SADCC) : part of a whole or a cover?
- Authors: Lubbe, Ingrid Lisa
- Date: 1990
- Subjects: Southern African Development Coordination Conference
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:2753 , http://hdl.handle.net/10962/d1002000
- Description: The object of this analysis of the Southern African Development Coordination Conference (SADCC) was to examine the interaction between the states which comprise the organisation in terms of regional and international factors which either facilitated or constrained the pursuit of the organisation's economic goals. To this end a theoretical orientation which would place the organisation in context of regional and international political and economic interaction was necessary. International regime theory was used to place the organisation in an international context, and at the same time provided a theoretical dimension which could be used to analyse empirical evidence on the SADCC organisation's functioning. The application of regime theory clearly highlighted the fact that SADCC's economic goals are constrained by the degree to which all of the SADCC states are integrated on the economic level with western market economy and furthermore , by the fact that these links are reinforced for seven of the nine SADCC states by their economic dependence on South Africa. The above conclusion showed that in terms of the perpetuation of the SADCC organisation as an economic regime, according to the regime theory outlined in Chapter One, the goals of SADCC did not create a firm basis for economic cooperation in the long term. The future of the SADCC organisation in it's present form will depend on how long the racial policies of South Africa continue, for the analysis makes clear that the organisation has much more political than economic coherency. The use of a regime framework showed that in terms of the SADCC states individual economic positions, the historical and structural links between South Africa, the majority of the SADCC states and the West will continue indefinitely due to the strength of the structural economic links between the Southern African region and the western market economy. Thus the analysis proves, within the parameters of international regime theory, the lack of economic coherency within the SADCC organisation's goals, and the strength of the economic ties between the Southern African region and the West.
- Full Text:
- Date Issued: 1990
- Authors: Lubbe, Ingrid Lisa
- Date: 1990
- Subjects: Southern African Development Coordination Conference
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:2753 , http://hdl.handle.net/10962/d1002000
- Description: The object of this analysis of the Southern African Development Coordination Conference (SADCC) was to examine the interaction between the states which comprise the organisation in terms of regional and international factors which either facilitated or constrained the pursuit of the organisation's economic goals. To this end a theoretical orientation which would place the organisation in context of regional and international political and economic interaction was necessary. International regime theory was used to place the organisation in an international context, and at the same time provided a theoretical dimension which could be used to analyse empirical evidence on the SADCC organisation's functioning. The application of regime theory clearly highlighted the fact that SADCC's economic goals are constrained by the degree to which all of the SADCC states are integrated on the economic level with western market economy and furthermore , by the fact that these links are reinforced for seven of the nine SADCC states by their economic dependence on South Africa. The above conclusion showed that in terms of the perpetuation of the SADCC organisation as an economic regime, according to the regime theory outlined in Chapter One, the goals of SADCC did not create a firm basis for economic cooperation in the long term. The future of the SADCC organisation in it's present form will depend on how long the racial policies of South Africa continue, for the analysis makes clear that the organisation has much more political than economic coherency. The use of a regime framework showed that in terms of the SADCC states individual economic positions, the historical and structural links between South Africa, the majority of the SADCC states and the West will continue indefinitely due to the strength of the structural economic links between the Southern African region and the western market economy. Thus the analysis proves, within the parameters of international regime theory, the lack of economic coherency within the SADCC organisation's goals, and the strength of the economic ties between the Southern African region and the West.
- Full Text:
- Date Issued: 1990
The spiral curriculum, integrated teaching and structured learning of mathematics at the secondary level
- Authors: Alummoottil, Joseph Michael
- Date: 1990
- Subjects: Mathematics -- Study and teaching (Secondary) -- South Africa Learning -- Mathematical models -- Research
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1769 , http://hdl.handle.net/10962/d1003654
- Description: The investigator's experience of teaching mathematics at a college of education since 1983 has reinforced his conviction that trainee students come to college with significant gaps, weaknesses and faults in their (mathematical) conceptual structures, probably as a result of shortcomings in the mathematics teaching to which they have been exposed. The theme of this investigation is thus a natural choice that appeared to be of immediate relevance to secondary school mathematics teaching. The analysis of the issue leads to a unified perspective: the problem is placed in a theoretical framework where Bruner [spiral curriculum], Ausubel [structured learning] and Skemp [relational understanding] are brought together. How the curriculum, textbooks and examination influence school mathematics teaching is examined in some depth and the consequences investigated. Two specific topics, viz. the generalised Pythagorean relation and absolute value are investigated in relation to published work, curriculum and textbooks, and each (topic) is presented as a unifying theme in secondary mathematics to standard 9 pupils. The classroom exercise is assessed to test the hypothesis that structured, integrated presentation around a spiral curriculum promotes "relational understanding". Analysis of results supports the hypothesis.
- Full Text:
- Date Issued: 1990
- Authors: Alummoottil, Joseph Michael
- Date: 1990
- Subjects: Mathematics -- Study and teaching (Secondary) -- South Africa Learning -- Mathematical models -- Research
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1769 , http://hdl.handle.net/10962/d1003654
- Description: The investigator's experience of teaching mathematics at a college of education since 1983 has reinforced his conviction that trainee students come to college with significant gaps, weaknesses and faults in their (mathematical) conceptual structures, probably as a result of shortcomings in the mathematics teaching to which they have been exposed. The theme of this investigation is thus a natural choice that appeared to be of immediate relevance to secondary school mathematics teaching. The analysis of the issue leads to a unified perspective: the problem is placed in a theoretical framework where Bruner [spiral curriculum], Ausubel [structured learning] and Skemp [relational understanding] are brought together. How the curriculum, textbooks and examination influence school mathematics teaching is examined in some depth and the consequences investigated. Two specific topics, viz. the generalised Pythagorean relation and absolute value are investigated in relation to published work, curriculum and textbooks, and each (topic) is presented as a unifying theme in secondary mathematics to standard 9 pupils. The classroom exercise is assessed to test the hypothesis that structured, integrated presentation around a spiral curriculum promotes "relational understanding". Analysis of results supports the hypothesis.
- Full Text:
- Date Issued: 1990
The stock identification of the Cape horse mackerel, Trachurus trachurus capensis (Pisces: Carangidae)
- Authors: Naish, Kerry-Ann
- Date: 1990
- Subjects: Carangidae -- Identification , Trachurus trachurus -- Identification , Carangidae -- South Africa , Trachurus trachurus -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5320 , http://hdl.handle.net/10962/d1005165 , Carangidae -- Identification , Trachurus trachurus -- Identification , Carangidae -- South Africa , Trachurus trachurus -- South Africa
- Description: Three stocks of the Cape horse mackerel, Trachurus trachurus capensis, have been recognised in the ICSEAF convention region off southern Africa (Figure 1) on the basis of catch distribution and biological analyses. They were identified as being off Namibia (ICSEAF Divisions 1 . 3 and 1.4), off the West Coast of South Africa (Div. 1.6) and off the South Coast (Div. 2.1 and 2.2). Recently, speculation as to the accuracy of the classification of the South African populations has arisen. The aim of this study was to determine the number of stocks In Divisions 1.6, 2.1 and 2.2, using methodology which assessed the spatial and temporal nature and the phenotypic and genotypic characteristics of the species. The distribution of horse mackerel was evaluated by studying the trends in catch data and length frequency distributions obtained from the demersal industry during 1986 to 1988 and from the demersal biomass cruises in 1987 and 1988. Adult fish, found in Div. 2.1 and 2.2, probably migrated; during the months in which horse mackerel were expected to spawn, CPUE values were higher over the central Agulhas Bank than in the east of the study region. During the quiescent period, catches and numbers were higher in the latter region. Juvenile horse mackerel were found in the nursery areas utilised by pelagic fish and it is likely that they were transported northward from the Agulhas Bank. A decrease in biomass of individuals in Div. 1.5 indicated a separation between a northern and a southern population. Analyses of the phenotype, or epigenetic characters, of horse mackerel were used as a further test of stock integrity. Monthly samples were drawn from Div. 1.6, 2.1 and 2.2 during May 1988 to June, 1989. Comparisons for the values obtained from growth, length-at-50%-maturity and the season of otolith ring formation from each region showed no significant variation in the phenotype. Morphometric analysis proved inconclusive. Monthly gonadosomatic indices show that fish south of the Orange River share the same spawning season. Reports from the literature show that horse mackerel in the latter region differ from those of northern Namibia in spawning season, age-at-50%-maturity and season of otolith ring formation. The genetic structure of the populations of horse mackerel was evaluated by means of a restriction enzyme analysis of the Mitochondrial DNA of 37 fish collected from Divisions 1.4, 1.5, 1.6, 2.1 and 2.2. Two composite genotypes of horse mackerel were found; one belonging to fish in Div. 1.4 and one to fish in Div. 1.6, 2.1 and 2.2. The genetic distance between the two genotypes, 0.07, was the expected distance between two populations at a subspecies level. Fish in Div. 1.5 consisted of both genotypes and may be a region of mixing between the two populations. The interpretation of results was cautioned; prevlous work has shown that the migration of a small number of individuals between two stocks can be expected to maintain a low variation between the populations. In concluding, it was recommended that the horse mackerel be managed as two stocks, one in Div. 1.3 and 1.4 and one in Div. 1.6, 2.1 and 2.2
- Full Text:
- Date Issued: 1990
- Authors: Naish, Kerry-Ann
- Date: 1990
- Subjects: Carangidae -- Identification , Trachurus trachurus -- Identification , Carangidae -- South Africa , Trachurus trachurus -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5320 , http://hdl.handle.net/10962/d1005165 , Carangidae -- Identification , Trachurus trachurus -- Identification , Carangidae -- South Africa , Trachurus trachurus -- South Africa
- Description: Three stocks of the Cape horse mackerel, Trachurus trachurus capensis, have been recognised in the ICSEAF convention region off southern Africa (Figure 1) on the basis of catch distribution and biological analyses. They were identified as being off Namibia (ICSEAF Divisions 1 . 3 and 1.4), off the West Coast of South Africa (Div. 1.6) and off the South Coast (Div. 2.1 and 2.2). Recently, speculation as to the accuracy of the classification of the South African populations has arisen. The aim of this study was to determine the number of stocks In Divisions 1.6, 2.1 and 2.2, using methodology which assessed the spatial and temporal nature and the phenotypic and genotypic characteristics of the species. The distribution of horse mackerel was evaluated by studying the trends in catch data and length frequency distributions obtained from the demersal industry during 1986 to 1988 and from the demersal biomass cruises in 1987 and 1988. Adult fish, found in Div. 2.1 and 2.2, probably migrated; during the months in which horse mackerel were expected to spawn, CPUE values were higher over the central Agulhas Bank than in the east of the study region. During the quiescent period, catches and numbers were higher in the latter region. Juvenile horse mackerel were found in the nursery areas utilised by pelagic fish and it is likely that they were transported northward from the Agulhas Bank. A decrease in biomass of individuals in Div. 1.5 indicated a separation between a northern and a southern population. Analyses of the phenotype, or epigenetic characters, of horse mackerel were used as a further test of stock integrity. Monthly samples were drawn from Div. 1.6, 2.1 and 2.2 during May 1988 to June, 1989. Comparisons for the values obtained from growth, length-at-50%-maturity and the season of otolith ring formation from each region showed no significant variation in the phenotype. Morphometric analysis proved inconclusive. Monthly gonadosomatic indices show that fish south of the Orange River share the same spawning season. Reports from the literature show that horse mackerel in the latter region differ from those of northern Namibia in spawning season, age-at-50%-maturity and season of otolith ring formation. The genetic structure of the populations of horse mackerel was evaluated by means of a restriction enzyme analysis of the Mitochondrial DNA of 37 fish collected from Divisions 1.4, 1.5, 1.6, 2.1 and 2.2. Two composite genotypes of horse mackerel were found; one belonging to fish in Div. 1.4 and one to fish in Div. 1.6, 2.1 and 2.2. The genetic distance between the two genotypes, 0.07, was the expected distance between two populations at a subspecies level. Fish in Div. 1.5 consisted of both genotypes and may be a region of mixing between the two populations. The interpretation of results was cautioned; prevlous work has shown that the migration of a small number of individuals between two stocks can be expected to maintain a low variation between the populations. In concluding, it was recommended that the horse mackerel be managed as two stocks, one in Div. 1.3 and 1.4 and one in Div. 1.6, 2.1 and 2.2
- Full Text:
- Date Issued: 1990
The taxonomy and life history of the blue stingray, Dasyatis marmorata capensis (Batoidea : Dasyatidae) from Southern Africa
- Cowley, Paul D (Paul Denfer), 1964-
- Authors: Cowley, Paul D (Paul Denfer), 1964-
- Date: 1990
- Subjects: Stingrays -- Africa, Southern Dasyatidae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5183 , http://hdl.handle.net/10962/d1001959
- Description: The blue stingray, Dasyatis marmorata capensis is an important recreational shore angling species, especially amongst tournament anglers, in South Africa. The taxonomy and aspects of the biology of this species were investigated from specimens collected between March 1987 and May 1989, from various localities along the southern African coastline. Morphological comparisons were made between Dasyatis pastinaca, Dasyatis marmorata and the local variety. The results indicated that the local variety is different to D. pastinaca in colouration, disc length size, and vertebral and radial counts. The proposed new sub-species Dasyatis marmorata capensis is closest to Dasyatis marmorata of the north-eastern Atlantic coast, but differs in snout angle, disc length and snout to vent length. Analysis of catch per unit of effort data revealed that the blue stingray exhibits distinct seasonality. Adult and sub-adult fish undertake an annual onshore/offshore migration and invade the inshore region between spring and summer, while juveniles remain offshore and utilize this zone as a nursery area. Length-at-age and growth rates for both sexes were estimated from bands formed seasonally in the vertebral centra. The derived von Bertalanffy growth parameters indicated that females reach a greater asymptotic size (913.8 mm DW) and have a slower growth rate (K = -0.07) than males (531.8 mm DW, K = -0.17). Growth rates of juvenile captive specimens compared favourably with back calculated values, at approximately 65 mm/year, for the first year of growth. Dasyatis marmorata capensis is an aplacental viviparous elasmobranch with a well defined annual breeding cycle. Young are released , at a size of 170-200 mm DW, from October to December after a gestation period of approximately nine months. An average fecundity of 3.07 was calculated . Examination of gonadal development indicated that sexual maturity is first attained at a size of 408 and 500 mm DW in males and females, respectively, corresponding to ages 4.5 and 7 years. Size-related food habits were determined independently from three depth zones. The major prey items for each size class were directly related to the abundance of the infauna of the different depth zones. Polychaeta, amphipoda and stomatopoda were the major prey items in the offshore zone. In the nearshore zone, the dominant prey species were Balanoglossus capensis and Callianassa spp .. The high incidence of empty stomachs and the presence of prey items which occur in greatest abundance beyond the surf zone indicated that this zone is not utilized for the purposes of feeding.
- Full Text:
- Date Issued: 1990
- Authors: Cowley, Paul D (Paul Denfer), 1964-
- Date: 1990
- Subjects: Stingrays -- Africa, Southern Dasyatidae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5183 , http://hdl.handle.net/10962/d1001959
- Description: The blue stingray, Dasyatis marmorata capensis is an important recreational shore angling species, especially amongst tournament anglers, in South Africa. The taxonomy and aspects of the biology of this species were investigated from specimens collected between March 1987 and May 1989, from various localities along the southern African coastline. Morphological comparisons were made between Dasyatis pastinaca, Dasyatis marmorata and the local variety. The results indicated that the local variety is different to D. pastinaca in colouration, disc length size, and vertebral and radial counts. The proposed new sub-species Dasyatis marmorata capensis is closest to Dasyatis marmorata of the north-eastern Atlantic coast, but differs in snout angle, disc length and snout to vent length. Analysis of catch per unit of effort data revealed that the blue stingray exhibits distinct seasonality. Adult and sub-adult fish undertake an annual onshore/offshore migration and invade the inshore region between spring and summer, while juveniles remain offshore and utilize this zone as a nursery area. Length-at-age and growth rates for both sexes were estimated from bands formed seasonally in the vertebral centra. The derived von Bertalanffy growth parameters indicated that females reach a greater asymptotic size (913.8 mm DW) and have a slower growth rate (K = -0.07) than males (531.8 mm DW, K = -0.17). Growth rates of juvenile captive specimens compared favourably with back calculated values, at approximately 65 mm/year, for the first year of growth. Dasyatis marmorata capensis is an aplacental viviparous elasmobranch with a well defined annual breeding cycle. Young are released , at a size of 170-200 mm DW, from October to December after a gestation period of approximately nine months. An average fecundity of 3.07 was calculated . Examination of gonadal development indicated that sexual maturity is first attained at a size of 408 and 500 mm DW in males and females, respectively, corresponding to ages 4.5 and 7 years. Size-related food habits were determined independently from three depth zones. The major prey items for each size class were directly related to the abundance of the infauna of the different depth zones. Polychaeta, amphipoda and stomatopoda were the major prey items in the offshore zone. In the nearshore zone, the dominant prey species were Balanoglossus capensis and Callianassa spp .. The high incidence of empty stomachs and the presence of prey items which occur in greatest abundance beyond the surf zone indicated that this zone is not utilized for the purposes of feeding.
- Full Text:
- Date Issued: 1990
The taxonomy, biogeography and biology of cow and frilled sharks (Chondrichthyes : Hexanchiformes)
- Authors: Ebert, David A
- Date: 1990
- Subjects: Chondrichthyes Hexanchiformes Sharks
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5186 , http://hdl.handle.net/10962/d1001962
- Description: This study was undertaken to investigate the taxonomy, biogeography and biology of cow and frilled sharks (Chondrichthyes: Hexanchiformes). This taxon comprises two families, four genera and six extant species. The hexanchoids are a distinctive group of sharks characterized by six or seven paired gill openings, a single dorsal fin and an anal fin. Adult males of this group lack a siphon sac, but have in its place a clasper sac. This structure, which develops along the claspers, is unique to the Hexanchiformes. Hexanchoid sharks are widely distributed in area and depth. This group ranges from coastal bays and harbors along the open coast out across the continental shelf and down along the slopes to considerable depths. They occur from the equatorial zone to sub-polar regions. However, little is known about the ecology and life history of these sharks. Intraspecific variation of meristic counts were generally low for the Hexanchidae, but high for the Chlamydoselachidae, indicating that subpopulations, subspecies or even additional, new species exist within this family. Based on the indicators used in this study, maturity in male frilled sharks was attained at 916 mm TL, perlon sharks between 700 and 800 mm TL, sixgill sharks approximately 3140 mm TL, bigeyed sixgill sharks at about 1250 mm TL and sevengill sharks at approximately 1550 mm TL. Male reproductive success did not appear to be seasonal since males were found to contain viable sperm all year round. Female perlon sharks begin maturing between 950 mm and 1100 mm TL. Gravid females and newborns were absent from the other size classes and it is suspected that they aggregate in different locations to those of adult males and non-breeding females. Adult females are known at 4210 mm TL and immature at 3500 mm TL, However, a more accurate estimate of the size at maturity is wanting. Newborn sixgills were caught off southern Namibia during mid to late summer over three successive seasons. The occurrence of gravid females carrying term embryos during spring months and newborns during the summer months suggests a late spring or summer pupping period. Sixgill and sevengill sharks give birth in areas of high primary productivity. Energetically, this is advantageous for the newborns to be placed in an area with an abundant food source. The rapid growth rates of sixgill and sevengill sharks over the first year would enhance their survivorship since neither species has many predators. The number of female sevengills entering the breeding population is regulated to ensure that some portion of the population is reproductively active at any one time. The "staggering" of females which enter into the breeding population in any given year indicates a two year reproductive cycle. Fecundity estimates for 19 specimens with a largest egg diameter of at least 40 mm indicates a litter size of 67 to 104. The recapture of an adult female sevengill in approximately the same location in which it was tagged suggests that the same individual sharks may return to the same breeding grounds. As with any predators, sharks tend to exploit advantages over their prey. The hexanchoids, especially the sevengill, have evolved complex foraging strategies including social facilitation whereby they actively hunt in packs for large prey species. Sharks of the order Hexanchiformes, although lacking the diversity of the major shark orders, nonetheless play an integral role in the marine environment. The group's success can be attributed to their apical trophic position. In most habitats in which they occur, hexanchoids have no comparable competitors since equivalent sized sympatric squaloids and carcharhinoids feed at a lower trophic level.
- Full Text:
- Date Issued: 1990
- Authors: Ebert, David A
- Date: 1990
- Subjects: Chondrichthyes Hexanchiformes Sharks
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5186 , http://hdl.handle.net/10962/d1001962
- Description: This study was undertaken to investigate the taxonomy, biogeography and biology of cow and frilled sharks (Chondrichthyes: Hexanchiformes). This taxon comprises two families, four genera and six extant species. The hexanchoids are a distinctive group of sharks characterized by six or seven paired gill openings, a single dorsal fin and an anal fin. Adult males of this group lack a siphon sac, but have in its place a clasper sac. This structure, which develops along the claspers, is unique to the Hexanchiformes. Hexanchoid sharks are widely distributed in area and depth. This group ranges from coastal bays and harbors along the open coast out across the continental shelf and down along the slopes to considerable depths. They occur from the equatorial zone to sub-polar regions. However, little is known about the ecology and life history of these sharks. Intraspecific variation of meristic counts were generally low for the Hexanchidae, but high for the Chlamydoselachidae, indicating that subpopulations, subspecies or even additional, new species exist within this family. Based on the indicators used in this study, maturity in male frilled sharks was attained at 916 mm TL, perlon sharks between 700 and 800 mm TL, sixgill sharks approximately 3140 mm TL, bigeyed sixgill sharks at about 1250 mm TL and sevengill sharks at approximately 1550 mm TL. Male reproductive success did not appear to be seasonal since males were found to contain viable sperm all year round. Female perlon sharks begin maturing between 950 mm and 1100 mm TL. Gravid females and newborns were absent from the other size classes and it is suspected that they aggregate in different locations to those of adult males and non-breeding females. Adult females are known at 4210 mm TL and immature at 3500 mm TL, However, a more accurate estimate of the size at maturity is wanting. Newborn sixgills were caught off southern Namibia during mid to late summer over three successive seasons. The occurrence of gravid females carrying term embryos during spring months and newborns during the summer months suggests a late spring or summer pupping period. Sixgill and sevengill sharks give birth in areas of high primary productivity. Energetically, this is advantageous for the newborns to be placed in an area with an abundant food source. The rapid growth rates of sixgill and sevengill sharks over the first year would enhance their survivorship since neither species has many predators. The number of female sevengills entering the breeding population is regulated to ensure that some portion of the population is reproductively active at any one time. The "staggering" of females which enter into the breeding population in any given year indicates a two year reproductive cycle. Fecundity estimates for 19 specimens with a largest egg diameter of at least 40 mm indicates a litter size of 67 to 104. The recapture of an adult female sevengill in approximately the same location in which it was tagged suggests that the same individual sharks may return to the same breeding grounds. As with any predators, sharks tend to exploit advantages over their prey. The hexanchoids, especially the sevengill, have evolved complex foraging strategies including social facilitation whereby they actively hunt in packs for large prey species. Sharks of the order Hexanchiformes, although lacking the diversity of the major shark orders, nonetheless play an integral role in the marine environment. The group's success can be attributed to their apical trophic position. In most habitats in which they occur, hexanchoids have no comparable competitors since equivalent sized sympatric squaloids and carcharhinoids feed at a lower trophic level.
- Full Text:
- Date Issued: 1990
The uses of transactional analysis in theatre practice : inaugural lecture delivered at Rhodes University
- Authors: James, Sydney
- Date: 1990
- Subjects: Transactional analysis , Theater -- Production and direction , Theater -- Psychological aspects
- Language: English
- Type: Text
- Identifier: vital:642 , http://hdl.handle.net/10962/d1020711 , ISBN 0868102067
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1990
- Authors: James, Sydney
- Date: 1990
- Subjects: Transactional analysis , Theater -- Production and direction , Theater -- Psychological aspects
- Language: English
- Type: Text
- Identifier: vital:642 , http://hdl.handle.net/10962/d1020711 , ISBN 0868102067
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1990
Title not specified
- Nonogcinile, Nomillion and group, Tracey, Andrew T N and Gerhard Kubik
- Authors: Nonogcinile, Nomillion and group , Tracey, Andrew T N and Gerhard Kubik
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Overtone singing , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93532 , vital:30891 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC028a-09
- Description: Traditional Thembu song with umngqokolo overtone singing.
- Full Text: false
- Date Issued: 1990
- Authors: Nonogcinile, Nomillion and group , Tracey, Andrew T N and Gerhard Kubik
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Overtone singing , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93532 , vital:30891 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC028a-09
- Description: Traditional Thembu song with umngqokolo overtone singing.
- Full Text: false
- Date Issued: 1990
Title not specified
- Knowledge and group of Xhosa women, Tracey, Andrew T N
- Authors: Knowledge and group of Xhosa women , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Hand-clapping music , Drum music , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93914 , vital:30970 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC030-08
- Description: Traditional Thembu diviners song (amagqirha) accompanied by drums and clapping.
- Full Text: false
- Date Issued: 1990
- Authors: Knowledge and group of Xhosa women , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Hand-clapping music , Drum music , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93914 , vital:30970 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC030-08
- Description: Traditional Thembu diviners song (amagqirha) accompanied by drums and clapping.
- Full Text: false
- Date Issued: 1990
Title not specified
- Knowledge and group of Xhosa women, Tracey, Andrew T N
- Authors: Knowledge and group of Xhosa women , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Hand-clapping music , Drum music , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93948 , vital:30974 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC030-10
- Description: Traditional Thembu diviners song (amagqirha) accompanied by drums and clapping.
- Full Text: false
- Date Issued: 1990
- Authors: Knowledge and group of Xhosa women , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Hand-clapping music , Drum music , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93948 , vital:30974 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC030-10
- Description: Traditional Thembu diviners song (amagqirha) accompanied by drums and clapping.
- Full Text: false
- Date Issued: 1990
Title not specified
- Ngqoko married women villagers, Tracey, Andrew T N
- Authors: Ngqoko married women villagers , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Whistling music , folk dance , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93686 , vital:30915 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC029a-09
- Description: Traditional Thembu umngqungqo women's song for girls initiation accompanied by whistling.
- Full Text: false
- Date Issued: 1990
- Authors: Ngqoko married women villagers , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Whistling music , folk dance , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93686 , vital:30915 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC029a-09
- Description: Traditional Thembu umngqungqo women's song for girls initiation accompanied by whistling.
- Full Text: false
- Date Issued: 1990
Title not specified
- Kambazite Makorekore, Three other players, Tracey, Andrew T N
- Authors: Kambazite Makorekore , Three other players , Tracey, Andrew T N
- Date: 1990
- Subjects: Nyanja (African people) -- Malawi , Folk music -- Malawi , Percussion instruments -- Africa , Sub-Saharan African music , Africa Malawi Chileka f-sx
- Language: Nya
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/75195 , vital:30385 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC017-01
- Description: Traditional song with valimba xylophone and rattles accompaniment.
- Full Text: false
- Date Issued: 1990
- Authors: Kambazite Makorekore , Three other players , Tracey, Andrew T N
- Date: 1990
- Subjects: Nyanja (African people) -- Malawi , Folk music -- Malawi , Percussion instruments -- Africa , Sub-Saharan African music , Africa Malawi Chileka f-sx
- Language: Nya
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/75195 , vital:30385 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC017-01
- Description: Traditional song with valimba xylophone and rattles accompaniment.
- Full Text: false
- Date Issued: 1990
Title not specified
- Knowledge and group of Xhosa women, Tracey, Andrew T N
- Authors: Knowledge and group of Xhosa women , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Hand-clapping music , Drum music , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93909 , vital:30969 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC030-07
- Description: Traditional Thembu diviners song (amagqirha) accompanied by drums and clapping.
- Full Text: false
- Date Issued: 1990
- Authors: Knowledge and group of Xhosa women , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Hand-clapping music , Drum music , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93909 , vital:30969 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC030-07
- Description: Traditional Thembu diviners song (amagqirha) accompanied by drums and clapping.
- Full Text: false
- Date Issued: 1990
Title not specified
- Nonogcinile, Nomillion and group, Tracey, Andrew T N and Gerhard Kubik
- Authors: Nonogcinile, Nomillion and group , Tracey, Andrew T N and Gerhard Kubik
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Folk dance , Claves music , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93523 , vital:30890 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC028a-08
- Description: Traditional Thembu umngqungqo women's song for girls initiation accompanied by claves and gruff singing .
- Full Text: false
- Date Issued: 1990
- Authors: Nonogcinile, Nomillion and group , Tracey, Andrew T N and Gerhard Kubik
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Folk dance , Claves music , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93523 , vital:30890 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC028a-08
- Description: Traditional Thembu umngqungqo women's song for girls initiation accompanied by claves and gruff singing .
- Full Text: false
- Date Issued: 1990
Title not specified
- Nofinishi Dywili, Tracey, Andrew T N
- Authors: Nofinishi Dywili , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Stringed instrument , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93858 , vital:30963 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC030-05
- Description: Traditional Thembu song accompanied by uhadi bow.
- Full Text: false
- Date Issued: 1990
- Authors: Nofinishi Dywili , Tracey, Andrew T N
- Date: 1990
- Subjects: Xhosa (African people) -- South Africa , Folk music , Stringed instrument , Sub-Saharan African music , Africa South Africa Lady Frere f-sa
- Language: Xhosa
- Type: sound recordings , field recordings , Sound recording material
- Identifier: http://hdl.handle.net/10962/93858 , vital:30963 , International Library of African Music, Rhodes University, Grahamstown, South Africa , ATC030-05
- Description: Traditional Thembu song accompanied by uhadi bow.
- Full Text: false
- Date Issued: 1990