Attitudinal difference surveys perpetuate harmful tropes: A comment on Nattrass
- Rosenberg, Eureta, Le Grange, Lesley
- Authors: Rosenberg, Eureta , Le Grange, Lesley
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370129 , vital:66300 , xlink:href="https://doi.org/10.17159/sajs.2020/8469"
- Description: We reply to the article, ‘Why are black South African students less likely to consider studying biological sciences?’, authored by University of Cape Town (UCT) researcher Nicoli Nattrass1 and published in the South African Journal of Science on 27 May 2020. At the time of writing our reply the article had already received sharp criticism from the Black Academic Caucus at UCT and in a statement released on 5 June 2020, the UCT executive distanced itself from the content of the paper, inviting rigorous, respectful review of the published research. Nattrass’ article1 follows two papers published in 2019 by scholars associated with South African universities, both of which were widely denounced for the racist undertones of their content. The first article was authored by Stellenbosch University researchers who reported on low cognitive functioning of coloured women linked to education levels and lifestyles2 ; see comment by Le Grange3 . The second article was co-authored by an adjunct professor at UCT and examined the role of cognitive ability or intelligence on slave exports from Africa4 . These publications gave rise to a broader debate on enduring racism in science and the re-ascendency of race science internationally. In this reply, we focus on the methodology of attitudinal survey used for the study reported by Nattrass (and by many other scientists). There are two lines of argument that we weave together: the quality of the research as reported, and problems inherent to comparative attitudinal survey research (regardless of how well it is executed). It should be noted that the Black Academic Caucus at UCT has also critiqued the research design, identifying many of the points we make here, and they have additionally included a discourse analysis of the paper (circulated via e-mail). To demonstrate how problematic a survey design can be, particularly when it is not rigorously executed, we share data and observations that counter the apparent findings of Nattrass’ study. We then argue that the publication of this research, in this manner, is detrimental to the biodiversity sector in which the tropes being perpetuated, can cause enormous harm. In the process we hope to encourage scientists to be more reflexive about their methodology, and we encourage the South African Journal of Science to publish works that are worthy of the young people of this country - research in which they can recognise themselves, rather than being forced to look at reductionist portrayals, legitimised under the banner of science.
- Full Text:
- Date Issued: 2020
- Authors: Rosenberg, Eureta , Le Grange, Lesley
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370129 , vital:66300 , xlink:href="https://doi.org/10.17159/sajs.2020/8469"
- Description: We reply to the article, ‘Why are black South African students less likely to consider studying biological sciences?’, authored by University of Cape Town (UCT) researcher Nicoli Nattrass1 and published in the South African Journal of Science on 27 May 2020. At the time of writing our reply the article had already received sharp criticism from the Black Academic Caucus at UCT and in a statement released on 5 June 2020, the UCT executive distanced itself from the content of the paper, inviting rigorous, respectful review of the published research. Nattrass’ article1 follows two papers published in 2019 by scholars associated with South African universities, both of which were widely denounced for the racist undertones of their content. The first article was authored by Stellenbosch University researchers who reported on low cognitive functioning of coloured women linked to education levels and lifestyles2 ; see comment by Le Grange3 . The second article was co-authored by an adjunct professor at UCT and examined the role of cognitive ability or intelligence on slave exports from Africa4 . These publications gave rise to a broader debate on enduring racism in science and the re-ascendency of race science internationally. In this reply, we focus on the methodology of attitudinal survey used for the study reported by Nattrass (and by many other scientists). There are two lines of argument that we weave together: the quality of the research as reported, and problems inherent to comparative attitudinal survey research (regardless of how well it is executed). It should be noted that the Black Academic Caucus at UCT has also critiqued the research design, identifying many of the points we make here, and they have additionally included a discourse analysis of the paper (circulated via e-mail). To demonstrate how problematic a survey design can be, particularly when it is not rigorously executed, we share data and observations that counter the apparent findings of Nattrass’ study. We then argue that the publication of this research, in this manner, is detrimental to the biodiversity sector in which the tropes being perpetuated, can cause enormous harm. In the process we hope to encourage scientists to be more reflexive about their methodology, and we encourage the South African Journal of Science to publish works that are worthy of the young people of this country - research in which they can recognise themselves, rather than being forced to look at reductionist portrayals, legitimised under the banner of science.
- Full Text:
- Date Issued: 2020
The meaning and practice of stewardship in South Africa
- Cockburn, Jessica J, Cundill, Georgina, Shackleton, Sheona E, Rouget, Mathieu
- Authors: Cockburn, Jessica J , Cundill, Georgina , Shackleton, Sheona E , Rouget, Mathieu
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/390683 , vital:68574 , xlink:href="http://dx.doi.org/10.17159/sajs.2019/5339"
- Description: Stewardship offers a means of addressing social-ecological sustainability challenges, from the local to the global level. The concept of stewardship has had various meanings attached to it over time, and the links between the theory and practice of stewardship are not well understood. We sought to characterise the practice of stewardship in South Africa, to better understand the relationship between theory and practice. We found that practitioners’ understandings of stewardship coalesce around two core notions: the idea of stewardship as ‘responsible use and care’ of nature, and stewardship as a ‘balancing act’ between stewards’ use of natural resources for agricultural production and their responsibility to protect and manage the wider ecosystem. Stewardship practice in South Africa is strongly influenced by the biodiversity stewardship tool; however, many practitioners are integrating biodiversity stewardship with other approaches. These emerging social-ecological stewardship initiatives operate at landscape-level and work towards integrated social and ecological stewardship outcomes, by facilitating collaboration among diverse stakeholders. Further research is needed to better understand what is required to support these integrated, collaborative and cross-sectoral initiatives. Policy mechanisms that facilitate integrated place-based stewardship practice can contribute to expanding the practice of biodiversity stewardship in South Africa.
- Full Text:
- Date Issued: 2019
- Authors: Cockburn, Jessica J , Cundill, Georgina , Shackleton, Sheona E , Rouget, Mathieu
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/390683 , vital:68574 , xlink:href="http://dx.doi.org/10.17159/sajs.2019/5339"
- Description: Stewardship offers a means of addressing social-ecological sustainability challenges, from the local to the global level. The concept of stewardship has had various meanings attached to it over time, and the links between the theory and practice of stewardship are not well understood. We sought to characterise the practice of stewardship in South Africa, to better understand the relationship between theory and practice. We found that practitioners’ understandings of stewardship coalesce around two core notions: the idea of stewardship as ‘responsible use and care’ of nature, and stewardship as a ‘balancing act’ between stewards’ use of natural resources for agricultural production and their responsibility to protect and manage the wider ecosystem. Stewardship practice in South Africa is strongly influenced by the biodiversity stewardship tool; however, many practitioners are integrating biodiversity stewardship with other approaches. These emerging social-ecological stewardship initiatives operate at landscape-level and work towards integrated social and ecological stewardship outcomes, by facilitating collaboration among diverse stakeholders. Further research is needed to better understand what is required to support these integrated, collaborative and cross-sectoral initiatives. Policy mechanisms that facilitate integrated place-based stewardship practice can contribute to expanding the practice of biodiversity stewardship in South Africa.
- Full Text:
- Date Issued: 2019
Cytotoxic activity of marine sponge extracts from the sub-Antarctic Islands and the Southern Ocean
- Olsen, Elisabeth, De Cerf, Christopher, Dziwornu, Godwin A, Puccinelli, Eleonora, Parker-Nance, Shirley, Ansorge, Isabelle J, Samaai, Toufiek, Dingle, Laura M K, Edkins, Adrienne L, Sunassee, Suthananda N
- Authors: Olsen, Elisabeth , De Cerf, Christopher , Dziwornu, Godwin A , Puccinelli, Eleonora , Parker-Nance, Shirley , Ansorge, Isabelle J , Samaai, Toufiek , Dingle, Laura M K , Edkins, Adrienne L , Sunassee, Suthananda N
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66300 , vital:28931 , https://doi.org/10.17159/sajs.2016/20160202
- Description: publisher version , Over the past 50 years, marine invertebrates, especially sponges, have proven to be a valuable source of new and/or bioactive natural products that have the potential to be further developed as lead compounds for pharmaceutical applications. Although marine benthic invertebrate communities occurring off the coast of South Africa have been explored for their biomedicinal potential, the natural product investigation of marine sponges from the sub-Antarctic Islands in the Southern Ocean for the presence of bioactive secondary metabolites has been relatively unexplored thus far. We report here the results for the biological screening of both aqueous and organic extracts prepared from nine specimens of eight species of marine sponges, collected from around Marion Island and the Prince Edward Islands in the Southern Ocean, for their cytotoxic activity against three cancer cell lines. The results obtained through this multidisciplinary collaborative research effort by exclusively South African institutions has provided an exciting opportunity to discover cytotoxic compounds from sub-Antarctic sponges, whilst contributing to our understanding of the biodiversity and geographic distributions of these cold-water invertebrates. Therefore, we acknowledge here the various contributions of the diverse scientific disciplines that played a pivotal role in providing the necessary platform for the future natural products chemistry investigation of these marine sponges from the sub- Antarctic Islands and the Southern Ocean. Significance: This study will contribute to understanding the biodiversity and geographic distributions of sponges in the Southern Ocean. This multidisciplinary project has enabled the investigation of marine sponges for the presence of cytotoxic compounds. Further investigation will lead to the isolation and identification of cytotoxic compounds present in the active sponge extracts. , University of Cape Town; South African Medical Research Council; National Research Foundation (South Africa); CANSA; Rhodes University; Department of Science and Technology; Department of Environmental Affairs; SANAP
- Full Text:
- Date Issued: 2016
- Authors: Olsen, Elisabeth , De Cerf, Christopher , Dziwornu, Godwin A , Puccinelli, Eleonora , Parker-Nance, Shirley , Ansorge, Isabelle J , Samaai, Toufiek , Dingle, Laura M K , Edkins, Adrienne L , Sunassee, Suthananda N
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66300 , vital:28931 , https://doi.org/10.17159/sajs.2016/20160202
- Description: publisher version , Over the past 50 years, marine invertebrates, especially sponges, have proven to be a valuable source of new and/or bioactive natural products that have the potential to be further developed as lead compounds for pharmaceutical applications. Although marine benthic invertebrate communities occurring off the coast of South Africa have been explored for their biomedicinal potential, the natural product investigation of marine sponges from the sub-Antarctic Islands in the Southern Ocean for the presence of bioactive secondary metabolites has been relatively unexplored thus far. We report here the results for the biological screening of both aqueous and organic extracts prepared from nine specimens of eight species of marine sponges, collected from around Marion Island and the Prince Edward Islands in the Southern Ocean, for their cytotoxic activity against three cancer cell lines. The results obtained through this multidisciplinary collaborative research effort by exclusively South African institutions has provided an exciting opportunity to discover cytotoxic compounds from sub-Antarctic sponges, whilst contributing to our understanding of the biodiversity and geographic distributions of these cold-water invertebrates. Therefore, we acknowledge here the various contributions of the diverse scientific disciplines that played a pivotal role in providing the necessary platform for the future natural products chemistry investigation of these marine sponges from the sub- Antarctic Islands and the Southern Ocean. Significance: This study will contribute to understanding the biodiversity and geographic distributions of sponges in the Southern Ocean. This multidisciplinary project has enabled the investigation of marine sponges for the presence of cytotoxic compounds. Further investigation will lead to the isolation and identification of cytotoxic compounds present in the active sponge extracts. , University of Cape Town; South African Medical Research Council; National Research Foundation (South Africa); CANSA; Rhodes University; Department of Science and Technology; Department of Environmental Affairs; SANAP
- Full Text:
- Date Issued: 2016
Curiosity first, applications later
- Berold, Robert, Limson, Janice L
- Authors: Berold, Robert , Limson, Janice L
- Date: 2009
- Subjects: Nyokong, Tebello
- Language: English
- Type: Article , text
- Identifier: vital:7188 , http://hdl.handle.net/10962/d1006281 , http://www.sajs.co.za/sites/default/files/publications/pdf/1-4-1-PB.pdf , Nyokong, Tebello
- Description: Tebello Nyokong speaks to Robert Berold and Janice Limson about her career as a chemist. Tebello Nyokong, who holds a research chair in medicinal chemistry and nanotechnology at Rhodes University, has become the first South African scientist to win the L’Oreal-UNESCO award for women in science, in the physical sciences. Only one laureate is selected from each of five world regions, and Nyokong is the 2009 laureate for Africa and the Arab states. She and the winners from the other four regions travel to Paris in March to each accept the award and a generous prize of close to R1 million. Nyokong now heads the new Nanotechnology Innovation Centre for medical sensors: the biggest single research investment in the history of Rhodes. Linked to other nanotechnology centres in the country, it is designed to bridge the gap between research and the market.
- Full Text:
- Date Issued: 2009
- Authors: Berold, Robert , Limson, Janice L
- Date: 2009
- Subjects: Nyokong, Tebello
- Language: English
- Type: Article , text
- Identifier: vital:7188 , http://hdl.handle.net/10962/d1006281 , http://www.sajs.co.za/sites/default/files/publications/pdf/1-4-1-PB.pdf , Nyokong, Tebello
- Description: Tebello Nyokong speaks to Robert Berold and Janice Limson about her career as a chemist. Tebello Nyokong, who holds a research chair in medicinal chemistry and nanotechnology at Rhodes University, has become the first South African scientist to win the L’Oreal-UNESCO award for women in science, in the physical sciences. Only one laureate is selected from each of five world regions, and Nyokong is the 2009 laureate for Africa and the Arab states. She and the winners from the other four regions travel to Paris in March to each accept the award and a generous prize of close to R1 million. Nyokong now heads the new Nanotechnology Innovation Centre for medical sensors: the biggest single research investment in the history of Rhodes. Linked to other nanotechnology centres in the country, it is designed to bridge the gap between research and the market.
- Full Text:
- Date Issued: 2009
Establishing a basis for ecosystem management in the western Indian Ocean
- Vousden, David, Scott, Lucy E P, Sauer, Warwick H H, Bornman, T G, Ngoile, M, Stapley, J, Lutjeharms, Johan R E
- Authors: Vousden, David , Scott, Lucy E P , Sauer, Warwick H H , Bornman, T G , Ngoile, M , Stapley, J , Lutjeharms, Johan R E
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6774 , http://hdl.handle.net/10962/d1008081
- Description: An ambitious multinational programme, with generous funding for an initial five years, aims to provide understanding of marine resources for the benefit of impoverished island and coastal populations in a much-neglected ocean region.
- Full Text:
- Date Issued: 2008
- Authors: Vousden, David , Scott, Lucy E P , Sauer, Warwick H H , Bornman, T G , Ngoile, M , Stapley, J , Lutjeharms, Johan R E
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6774 , http://hdl.handle.net/10962/d1008081
- Description: An ambitious multinational programme, with generous funding for an initial five years, aims to provide understanding of marine resources for the benefit of impoverished island and coastal populations in a much-neglected ocean region.
- Full Text:
- Date Issued: 2008
Household fuelwood use in small electrified towns of the Makana District, Eastern Cape, South Africa
- Shackleton, Charlie M, Gambiza, James, Jones, R
- Authors: Shackleton, Charlie M , Gambiza, James , Jones, R
- Date: 2006
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182362 , vital:43823 , xlink:href="https://doi.org/10.17159/2413-3051/2007/v18i4a3394"
- Description: Access to secure energy supplies is a key foundation for sustainable development. Consequently local planning and development initiatives must be based on a sound knowledge of the energy use patterns and preferences of local users. This paper reports on such for three small urban settlements in the Eastern Cape Province, with a particular focus on fuelwood use. Despite widespread electrification over a decade ago, and perceptions that the ease of fuelwood collection was declining, most households continued to use fuelwood for cooking and space heating, whereas electricity was favoured for lighting. The most common reason for this was because fuelwood was cheap (or free) compared to electricity. Annual demand was approximately 1 450 kg per household per year. Households that collected their own supplies of fuelwood were significantly poorer than those that either bought their stocks, or those that did not use fuelwood at all. Indigenous species were favoured over exotic species, although fuelwood vendors traded mostly in exotic species, particularly Eucalyptus and wattle. The greater reliance of poorer and unelectrified households on fuelwood requires that local authorities consider this in energy planning, otherwise the poor will be neglected in policies such as the Free Basic Electricity.
- Full Text:
- Date Issued: 2006
Household fuelwood use in small electrified towns of the Makana District, Eastern Cape, South Africa
- Authors: Shackleton, Charlie M , Gambiza, James , Jones, R
- Date: 2006
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182362 , vital:43823 , xlink:href="https://doi.org/10.17159/2413-3051/2007/v18i4a3394"
- Description: Access to secure energy supplies is a key foundation for sustainable development. Consequently local planning and development initiatives must be based on a sound knowledge of the energy use patterns and preferences of local users. This paper reports on such for three small urban settlements in the Eastern Cape Province, with a particular focus on fuelwood use. Despite widespread electrification over a decade ago, and perceptions that the ease of fuelwood collection was declining, most households continued to use fuelwood for cooking and space heating, whereas electricity was favoured for lighting. The most common reason for this was because fuelwood was cheap (or free) compared to electricity. Annual demand was approximately 1 450 kg per household per year. Households that collected their own supplies of fuelwood were significantly poorer than those that either bought their stocks, or those that did not use fuelwood at all. Indigenous species were favoured over exotic species, although fuelwood vendors traded mostly in exotic species, particularly Eucalyptus and wattle. The greater reliance of poorer and unelectrified households on fuelwood requires that local authorities consider this in energy planning, otherwise the poor will be neglected in policies such as the Free Basic Electricity.
- Full Text:
- Date Issued: 2006
Observations of the habitats and biodiversity of the submarine canyons at Sodwana Bay
- Sink, K J, Boshoff, W, Samaai, Toufiek, Timm, P G, Kerwath, S E
- Authors: Sink, K J , Boshoff, W , Samaai, Toufiek , Timm, P G , Kerwath, S E
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6771 , http://hdl.handle.net/10962/d1008065
- Description: The discovery of coelacanths, Latimeria chalumnae, in Jesser Canyon off Sodwana Bay in northern KwaZulu-Natal in 2000 triggered renewed interest in the deep subtidal habitats associated with submarine canyons. Information stemming from three recreational Trimix diving expeditions in Wright and Jesser canyons between April 1998 and June 2001 revealed distinct and diverse invertebrate and fish communities in the canyons of the Greater St Lucia Wetland Park (GSLWP). In total, 69 invertebrate taxa were collected from Wright Canyon, including at least 15 new records for South Africa plus 11 potential new species and 16 range or depth extensions. Divers documented the first five coelacanth specimens and obtained information on fish distribution and abundance. Five different habitat types were recognized supporting distinct biological communities; the sandy plains outside of the canyons, scattered rock outcrops within the sandy plains, the canyon margin, canyon walls and caves and overhangs. The canyon margin is the richest habitat and supports dense communities of invertebrate suspension feeders, as well as a diverse and abundant fish fauna. Dominant canyon invertebrates included sponges, black corals, gorgonians, alcyonarian soft corals and stylasterine lace corals. These invertebrates support a diverse epifauna including basket- and brittlestars, winged oysters and other molluscs. The canyons within the GSLWP protect large populations of commercially important linefish species including the sparids, Chrysoblephus puniceus, C. anglicus, Polysteganus praeorbitalis and P. caeruleopunctatus, as well as several species of serranids and lutjanids. Additional biological sampling and standardized quantitative sampling within the canyons and deep reefs is required to develop a better understanding of their biological communities and the factors that shape them.
- Full Text:
- Date Issued: 2006
- Authors: Sink, K J , Boshoff, W , Samaai, Toufiek , Timm, P G , Kerwath, S E
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6771 , http://hdl.handle.net/10962/d1008065
- Description: The discovery of coelacanths, Latimeria chalumnae, in Jesser Canyon off Sodwana Bay in northern KwaZulu-Natal in 2000 triggered renewed interest in the deep subtidal habitats associated with submarine canyons. Information stemming from three recreational Trimix diving expeditions in Wright and Jesser canyons between April 1998 and June 2001 revealed distinct and diverse invertebrate and fish communities in the canyons of the Greater St Lucia Wetland Park (GSLWP). In total, 69 invertebrate taxa were collected from Wright Canyon, including at least 15 new records for South Africa plus 11 potential new species and 16 range or depth extensions. Divers documented the first five coelacanth specimens and obtained information on fish distribution and abundance. Five different habitat types were recognized supporting distinct biological communities; the sandy plains outside of the canyons, scattered rock outcrops within the sandy plains, the canyon margin, canyon walls and caves and overhangs. The canyon margin is the richest habitat and supports dense communities of invertebrate suspension feeders, as well as a diverse and abundant fish fauna. Dominant canyon invertebrates included sponges, black corals, gorgonians, alcyonarian soft corals and stylasterine lace corals. These invertebrates support a diverse epifauna including basket- and brittlestars, winged oysters and other molluscs. The canyons within the GSLWP protect large populations of commercially important linefish species including the sparids, Chrysoblephus puniceus, C. anglicus, Polysteganus praeorbitalis and P. caeruleopunctatus, as well as several species of serranids and lutjanids. Additional biological sampling and standardized quantitative sampling within the canyons and deep reefs is required to develop a better understanding of their biological communities and the factors that shape them.
- Full Text:
- Date Issued: 2006
A newly discovered population of the critically endangered false limpet Siphonaria compressa Allanson, 1958 (Pulmonata: Siphonariidae), with observations on its reproductive biology
- Allanson, Brian R, Herbert, D G
- Authors: Allanson, Brian R , Herbert, D G
- Date: 2005-05-23
- Language: English
- Type: Article
- Identifier: vital:6833 , http://hdl.handle.net/10962/d1007570
- Description: The endangered false limpet, Siphonaria compressa, originally described by Allanson in 1958 from Langebaan Lagoon, Saldanha, has been found living in intertidal eelgrass meadows in the embayment of the Knysna River estuary at Bollard Bay, Leisure Isle, Knysna, South Africa. This represents only the second known site of occurrence of the species. Although classified by the IUCN as critically endangered, the Knysna population is viable. , Acrobat Distiller 6.0 (Windows)
- Full Text:
- Authors: Allanson, Brian R , Herbert, D G
- Date: 2005-05-23
- Language: English
- Type: Article
- Identifier: vital:6833 , http://hdl.handle.net/10962/d1007570
- Description: The endangered false limpet, Siphonaria compressa, originally described by Allanson in 1958 from Langebaan Lagoon, Saldanha, has been found living in intertidal eelgrass meadows in the embayment of the Knysna River estuary at Bollard Bay, Leisure Isle, Knysna, South Africa. This represents only the second known site of occurrence of the species. Although classified by the IUCN as critically endangered, the Knysna population is viable. , Acrobat Distiller 6.0 (Windows)
- Full Text:
Monitoring the oceanic flow between Africa and Antarctica: report of the first Good Hope cruise
- Ansorge, Isabelle J, Speich, S, Lutjeharms, Johan R E, Goni, G J, Rautenbach, C J de W, Froneman, P William, Rouault, M, Garzoli, S
- Authors: Ansorge, Isabelle J , Speich, S , Lutjeharms, Johan R E , Goni, G J , Rautenbach, C J de W , Froneman, P William , Rouault, M , Garzoli, S
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6832 , http://hdl.handle.net/10962/d1007568
- Description: The Southern Ocean plays a major role in the global oceanic circulation, as a component of the Meridional Overturning Circulation, and it is postulated that it has a great influence on present-day climate. However, our understanding of its complex three-dimensional dynamics and of the impact of its variability on the climate system is rudimentary. The newly constituted, international GoodHope research venture aims to address this knowledge gap by establishing a programme of regular observations across the Southern Ocean between the African and Antarctic continents. The objectives of this programme are fivefold: (1) to improve understanding of Indo-Atlantic inter-ocean exchanges and their impact on the global thermohaline circulation and thus on global climate change; (2) to understand in more detail the influence these exchanges have on the climate variability of the southern African subcontinent; (3) to monitor the variability of the main Southern Ocean frontal systems associated with the Antarctic Circumpolar Current; (4) to study air-sea exchanges and their role on the global heat budget, with particular emphasis on the intense exchanges occurring within the Agulhas Retroflection region south of South Africa, and (5) to examine the role of major frontal systems as areas of elevated biological activity and as biogeographical barriers to the distribution of plankton. We present here preliminary results on the physical and biological structure of the frontal systems using the first GoodHope transect that was completed during February-March 2004.
- Full Text:
- Date Issued: 2005
- Authors: Ansorge, Isabelle J , Speich, S , Lutjeharms, Johan R E , Goni, G J , Rautenbach, C J de W , Froneman, P William , Rouault, M , Garzoli, S
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6832 , http://hdl.handle.net/10962/d1007568
- Description: The Southern Ocean plays a major role in the global oceanic circulation, as a component of the Meridional Overturning Circulation, and it is postulated that it has a great influence on present-day climate. However, our understanding of its complex three-dimensional dynamics and of the impact of its variability on the climate system is rudimentary. The newly constituted, international GoodHope research venture aims to address this knowledge gap by establishing a programme of regular observations across the Southern Ocean between the African and Antarctic continents. The objectives of this programme are fivefold: (1) to improve understanding of Indo-Atlantic inter-ocean exchanges and their impact on the global thermohaline circulation and thus on global climate change; (2) to understand in more detail the influence these exchanges have on the climate variability of the southern African subcontinent; (3) to monitor the variability of the main Southern Ocean frontal systems associated with the Antarctic Circumpolar Current; (4) to study air-sea exchanges and their role on the global heat budget, with particular emphasis on the intense exchanges occurring within the Agulhas Retroflection region south of South Africa, and (5) to examine the role of major frontal systems as areas of elevated biological activity and as biogeographical barriers to the distribution of plankton. We present here preliminary results on the physical and biological structure of the frontal systems using the first GoodHope transect that was completed during February-March 2004.
- Full Text:
- Date Issued: 2005
An interdisciplinary cruise dedicated to understanding ocean eddies upstream of the Prince Edward Islands
- Ansorge, Isabelle J, Froneman, P William, Lutjeharms, Johan R E, Bernard, Kim S, Lange, Louise, Lukáč, D, Backburg, B, Blake, Justin, Bland, S, Burls, N, Davies-Coleman, Michael T, Gerber, R, Gildenhuys, S, Hayes-Foley, P, Ludford, A, Manzoni, T, Robertson, E, Southey, D, Swart, S, Van Rensburg, D, Wynne, S
- Authors: Ansorge, Isabelle J , Froneman, P William , Lutjeharms, Johan R E , Bernard, Kim S , Lange, Louise , Lukáč, D , Backburg, B , Blake, Justin , Bland, S , Burls, N , Davies-Coleman, Michael T , Gerber, R , Gildenhuys, S , Hayes-Foley, P , Ludford, A , Manzoni, T , Robertson, E , Southey, D , Swart, S , Van Rensburg, D , Wynne, S
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6830 , http://hdl.handle.net/10962/d1007566
- Description: A detailed hydrographic and biological survey was carried out in the region of the South-West Indian Ridge during April 2004. Altimetry and hydrographic data have identified this region as an area of high flow variability. Hydrographic data revealed that here the Subantarctic Polar Front (SAF) and Antarctic Polar Front (APF) converge to form a highly intense frontal system. Water masses identified during the survey showed a distinct separation in properties between the northwestern and southeastern corners. In the north-west, water masses were distinctly Subantarctic (>8.5°C, salinity >34.2), suggesting that the SAF lay extremely far to the south. In the southeast corner water masses were typical of the Antarctic zone, showing a distinct subsurface temperature minimum of <2.5°C. Total integrated chl-a concentration during the survey ranged from 4.15 to 22.81 mg chl-a m[superscript (-2)], with the highest concentrations recorded at stations occupied in the frontal region. These data suggest that the region of the South-West Indian Ridge represents not only an area of elevated biological activity but also acts as a strong biogeographic barrier to the spatial distribution of zooplankton.
- Full Text:
- Date Issued: 2004
- Authors: Ansorge, Isabelle J , Froneman, P William , Lutjeharms, Johan R E , Bernard, Kim S , Lange, Louise , Lukáč, D , Backburg, B , Blake, Justin , Bland, S , Burls, N , Davies-Coleman, Michael T , Gerber, R , Gildenhuys, S , Hayes-Foley, P , Ludford, A , Manzoni, T , Robertson, E , Southey, D , Swart, S , Van Rensburg, D , Wynne, S
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6830 , http://hdl.handle.net/10962/d1007566
- Description: A detailed hydrographic and biological survey was carried out in the region of the South-West Indian Ridge during April 2004. Altimetry and hydrographic data have identified this region as an area of high flow variability. Hydrographic data revealed that here the Subantarctic Polar Front (SAF) and Antarctic Polar Front (APF) converge to form a highly intense frontal system. Water masses identified during the survey showed a distinct separation in properties between the northwestern and southeastern corners. In the north-west, water masses were distinctly Subantarctic (>8.5°C, salinity >34.2), suggesting that the SAF lay extremely far to the south. In the southeast corner water masses were typical of the Antarctic zone, showing a distinct subsurface temperature minimum of <2.5°C. Total integrated chl-a concentration during the survey ranged from 4.15 to 22.81 mg chl-a m[superscript (-2)], with the highest concentrations recorded at stations occupied in the frontal region. These data suggest that the region of the South-West Indian Ridge represents not only an area of elevated biological activity but also acts as a strong biogeographic barrier to the spatial distribution of zooplankton.
- Full Text:
- Date Issued: 2004
Evolution of Labeo victorianus predates the Pleistocene desiccation of Lake Victoria: evidence from mitochondrial DNA sequence variation
- Rutaisire, Justus, Booth, Anthony J, Masembe, C, Nyakaana, S, Muwanika, V B
- Authors: Rutaisire, Justus , Booth, Anthony J , Masembe, C , Nyakaana, S , Muwanika, V B
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6762 , http://hdl.handle.net/10962/d1007924
- Description: Geological data show that Lake Victoria dried out some 15 000 years ago. These data suggest that the entire faunal diversity within the lake has evolved since this time. However, mitochondrial DNA sequence diversity in the endemic cyprinid fish, Labeo victorianus, was high (24 haplotypes in 38 individuals; percentage sequence divergence of 0.74%), suggesting that the evolution of this species predates this Late Pleistocene climatological event. This finding is consistent with what has been reported earlier for cichlid fishes in the lake.
- Full Text:
- Date Issued: 2004
- Authors: Rutaisire, Justus , Booth, Anthony J , Masembe, C , Nyakaana, S , Muwanika, V B
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6762 , http://hdl.handle.net/10962/d1007924
- Description: Geological data show that Lake Victoria dried out some 15 000 years ago. These data suggest that the entire faunal diversity within the lake has evolved since this time. However, mitochondrial DNA sequence diversity in the endemic cyprinid fish, Labeo victorianus, was high (24 haplotypes in 38 individuals; percentage sequence divergence of 0.74%), suggesting that the evolution of this species predates this Late Pleistocene climatological event. This finding is consistent with what has been reported earlier for cichlid fishes in the lake.
- Full Text:
- Date Issued: 2004
Genetic analysis of the Octopus vulgaris population on the coast of South Africa
- Oosthuizen, Ané, Jiwaji, Meesbah, Shaw, Paul W
- Authors: Oosthuizen, Ané , Jiwaji, Meesbah , Shaw, Paul W
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6761 , http://hdl.handle.net/10962/d1007922
- Description: This study on Octopus vulgaris focused on the COIII gene region of mitochondrial DNA. Sequences from 21 samples from the Eastern Cape, and 14 samples from the Western Cape, were compared to determine whether different populations exist along the South African coast. A 380-bp segment of the COIII region of mtDNA was amplified using the polymerase chain reaction with specific designed primers. Phylogenetic inference was made using maximum parsimony (MP), maximum likelihood (ML), and distance based methods. All sequences conformed to a single haplotype. Lack of variation within and between east and west coast samples precluded further population genetic analysis. The sequence obtained in this study was also compared with other sequences lodged in the Genbank database. Phylogenetically, the South African O. vulgaris is closely related to O. vulgaris from Senegal (0.67% divergence) and the Mediterranean (1.51% divergence). Within the Mediterranean group, O. vulgaris from South Africa displayed less sequence divergence from Senegalese and Mediterranean individuals than O. vulgaris from Venezuela (3.85%) and Taiwan (3.87%). These data do not, therefore, refute the hypothesis of a single O. vulgaris genetic population around the coast.
- Full Text:
- Date Issued: 2004
- Authors: Oosthuizen, Ané , Jiwaji, Meesbah , Shaw, Paul W
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6761 , http://hdl.handle.net/10962/d1007922
- Description: This study on Octopus vulgaris focused on the COIII gene region of mitochondrial DNA. Sequences from 21 samples from the Eastern Cape, and 14 samples from the Western Cape, were compared to determine whether different populations exist along the South African coast. A 380-bp segment of the COIII region of mtDNA was amplified using the polymerase chain reaction with specific designed primers. Phylogenetic inference was made using maximum parsimony (MP), maximum likelihood (ML), and distance based methods. All sequences conformed to a single haplotype. Lack of variation within and between east and west coast samples precluded further population genetic analysis. The sequence obtained in this study was also compared with other sequences lodged in the Genbank database. Phylogenetically, the South African O. vulgaris is closely related to O. vulgaris from Senegal (0.67% divergence) and the Mediterranean (1.51% divergence). Within the Mediterranean group, O. vulgaris from South Africa displayed less sequence divergence from Senegalese and Mediterranean individuals than O. vulgaris from Venezuela (3.85%) and Taiwan (3.87%). These data do not, therefore, refute the hypothesis of a single O. vulgaris genetic population around the coast.
- Full Text:
- Date Issued: 2004
In situ feeding rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, in a temperate, temporarily open/closed Eastern Cape estuary
- Authors: Froneman, P William
- Date: 2004
- Language: English
- Type: text , Article
- Identifier: vital:6901 , http://hdl.handle.net/10962/d1011754
- Description: Size-fractionated chlorophyll-a (chl-a) concentrations and the in situ grazing rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, were assessed seasonally at the temporarily open/closed Kasouga estuary situated along the southeast coast of southern Africa. Total integrated chl-a concentration ranged between 1.17 and 12.18 mg chl-a m^(–3) and was always dominated by small phytoplankton cells (<20 μm), which comprised up to 86% (range 64–86%) of the total pigment. Total zooplankton abundance ranged between 2676 and 62 043 individuals m^(–3). These copepods numerically dominated the zooplankton counts, accounting for between 79% and 91% of the total. Gut pigment concentrations of the two species at night were significantly higher than the daytime values (P<0.05 in all cases). The observed pattern could be related to the marked diurnal vertical migration patterns exhibited by the copepods. Gut evacuation rates of P. hessei during the study ranged between 0.29 and 0.77 h^(–1) and between 0.39 and 0.58 h^(–1) for A. longipatella. The rate of gut pigment destruction for P. hessei and A. longipatella ranged between 55% and 81% and between 88% and 92% of the total chl-a ingested, respectively. The combined grazing impact of the two copepods ranged between 0.65 and 4.37 mg chl-a m^(–3), or between 4.3% and 35.9% of the available chl-a in the water column. Variations in the grazing activity of the two species could be attributed largely to seasonality in water temperature and shifts in the phytoplankton community structure and zooplankton abundance.
- Full Text:
- Date Issued: 2004
- Authors: Froneman, P William
- Date: 2004
- Language: English
- Type: text , Article
- Identifier: vital:6901 , http://hdl.handle.net/10962/d1011754
- Description: Size-fractionated chlorophyll-a (chl-a) concentrations and the in situ grazing rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, were assessed seasonally at the temporarily open/closed Kasouga estuary situated along the southeast coast of southern Africa. Total integrated chl-a concentration ranged between 1.17 and 12.18 mg chl-a m^(–3) and was always dominated by small phytoplankton cells (<20 μm), which comprised up to 86% (range 64–86%) of the total pigment. Total zooplankton abundance ranged between 2676 and 62 043 individuals m^(–3). These copepods numerically dominated the zooplankton counts, accounting for between 79% and 91% of the total. Gut pigment concentrations of the two species at night were significantly higher than the daytime values (P<0.05 in all cases). The observed pattern could be related to the marked diurnal vertical migration patterns exhibited by the copepods. Gut evacuation rates of P. hessei during the study ranged between 0.29 and 0.77 h^(–1) and between 0.39 and 0.58 h^(–1) for A. longipatella. The rate of gut pigment destruction for P. hessei and A. longipatella ranged between 55% and 81% and between 88% and 92% of the total chl-a ingested, respectively. The combined grazing impact of the two copepods ranged between 0.65 and 4.37 mg chl-a m^(–3), or between 4.3% and 35.9% of the available chl-a in the water column. Variations in the grazing activity of the two species could be attributed largely to seasonality in water temperature and shifts in the phytoplankton community structure and zooplankton abundance.
- Full Text:
- Date Issued: 2004
Science after a century at Rhodes University
- Authors: Woods, D R
- Date: 2004
- Language: English
- Type: Article , text
- Identifier: vital:7123 , http://hdl.handle.net/10962/d1006584
- Description: Rhodes Centenary issue , The small University of Rhodes (6142 students), in the rural city of Grahamstown, was established in 1904 as a result of a £50 000 grant from the Rhodes Trust in Oxford. It grew out of St Andrew’s College, which provided the first four professors and 41 students. The first paper from Rhodes in the South African Journal of Science (then called the Report of the South African Association for the Advancement of Science) was by Selmar Schonland, one of the university’s founding fathers. Entitled: ‘Biological and ethnological observations on a trip to the N.E. Kalahari’, it appeared in 1904. The following pages provide a glimpse into the growth and achievements of various departments in the faculties of Science and Pharmacy and associated institutes a century after the university was born.
- Full Text:
- Date Issued: 2004
- Authors: Woods, D R
- Date: 2004
- Language: English
- Type: Article , text
- Identifier: vital:7123 , http://hdl.handle.net/10962/d1006584
- Description: Rhodes Centenary issue , The small University of Rhodes (6142 students), in the rural city of Grahamstown, was established in 1904 as a result of a £50 000 grant from the Rhodes Trust in Oxford. It grew out of St Andrew’s College, which provided the first four professors and 41 students. The first paper from Rhodes in the South African Journal of Science (then called the Report of the South African Association for the Advancement of Science) was by Selmar Schonland, one of the university’s founding fathers. Entitled: ‘Biological and ethnological observations on a trip to the N.E. Kalahari’, it appeared in 1904. The following pages provide a glimpse into the growth and achievements of various departments in the faculties of Science and Pharmacy and associated institutes a century after the university was born.
- Full Text:
- Date Issued: 2004
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