Editors' choice

November/December 2017

Editor's Choice Nov/Dec 2017

On Saturday, I was a surgeon in South Africa, very little known. On Monday, I was world-renowned.” This was how South African heart transplant pioneer Chris Barnard summed up his instant rise to global fame after transplanting the first human heart – 50 years ago. On this 50th anniversary, Joubert examines the life of Chris Barnard and reflects on his scientific celebrity and that of scientists in South Africa today. [Read more]

Editor's Choice Nov/Dec 2017Rudman and colleagues provide a first perspective on the environmental impacts of emerging solar power developments in two arid biomes of South Africa: Nama-Karoo and Savanna. They investigated the direct environmental impacts of multiple solar power developments across the landscape of the Nama-Karoo and Savanna Biomes, at a larger scale than that of the environmental impact assessment (EIA) typically undertaken. [Read more]
Editor's Choice Nov/Dec 2017

Geothermal exploration should quantify South Africa’s geothermal resources and its potential impact toward the national renewable energy mix. Despite evidence of anomalously high geothermal gradients, geothermal energy is not yet considered a viable energy source for South Africa. [Read more]

Editor's Choice Nov/Dec 2017Most people think of algae as the green slimy substance in water. However, these microorganisms are found in an array of habitats including gold mine tailings facilities. These uninhabitable facilities need to be stabilised or revegetated to reduce pollution, leaching and erosion. They usually are stabilised with higher plants, but with variable and expensive results. [Read more]
Editor's Choice Nov/Dec 2017In this time of drought, the City of Cape Town’s water should be understood and managed as a single hydrological system, not by separation of environment, sanitation and water supply. Citizens have raised concerns about sewage pollution of the ocean from marine outfalls in Table Bay and other sites in Cape Town. At the same time, the City has proposed desalination of seawater to provide drinking water. [Read more]


September/October 2017

Editors' Choice: September/October 2017Recent findings place doubt on whether there is an economically extractable shale gas resource in South Africa’s Main Karoo Basin. The Main Karoo Basin has been identified as a potential shale gas resource, but resource estimates (of 13–390 Tcf) are highly speculative and based on theoretical calculations – which assume that free gas is preserved in the pore space of shales – and not direct measurements of actual gas content. [Read more]
Editors' Choice: September/October 2017Using local timber products improves the environmental impact of the truss and building industry in South Africa. Crafford and colleagues compared the environmental impacts of three roof truss systems – South African pine, Biligom® timber and light gauge steel – using a simplified life-cycle assessment. The two timber systems had overall the lowest environmental impact. [Read more]
Editors' Choice: September/October 2017More inclusive and reflective conservation management practices are needed for ecological sustainability in Cape Town. Cape Town has a rapidly growing, culturally and economically diverse citizenry with differing, sometimes conflicting, perspectives on local natural resources. The informal, cash economy of Cape Town’s poor includes the deeply cultural and spiritual world of traditional medicine or muthi. [Read more]
Editors' Choice: September/October 2017A comprehensive comparative analysis of life-cycle costs of all power generation technologies will be indispensable in guiding the development of future energy policies in South Africa. Based on conservative estimates, the value of the impacts of a coal-fired power station over its life cycle, is double to quadruple the price of electricity. [Read more]
Editors' Choice: September/October 2017DNA metabarcoding can transform the study of pollination. The identification of pollen carried by flower visitors is an essential first step in pollination biology. The skill and time required to identify pollen based on structure and morphology has been a major stumbling block in this field. DNA barcoding, using DNA extracted directly from pollen, offers an innovative alternative to traditional methods of pollen identification. [Read more]


July/August 2017

Editors'Choice: July/August 2017Science is the source and foundation of what makes it possible to meet the need for new knowledge, for its own sake and for its application and for the ability to keep doing better as the challenges we face grow greater. Yet science and its applications are frequently taken for granted rather than being understood as fundamental and essential parts of our lives, and scientists’ contributions all too often go unacknowledged. [Read more]
Editors' Choice: July/August 2017Extreme rainfalls are generally becoming heavier in the Western Cape Province of South Africa. De Waal and colleagues compared extreme rainfall in the 1980–2009 period to that in 1950–1979 and show that 63% of 76 rainfall stations analysed displayed an increase in rainfall extremes. There are similar trends of change for both 20- and 50-year return periods.  [Read more]
Editors' Choice: July/August 2017Women members in national science academies remain far below parity with men at 12%. Women members are better represented in the social sciences, humanities and arts, but rarely at over 20%; in the natural sciences and engineering, women’s membership remains well below 10%. [Read more]
Editors' Choice: July/August 2017Containing the spread of the Ebola virus disease outbreak in West Africa required more than treating the symptoms of the disease – both scientific and non-scientific interventions were required, according to Falade and Coultas. Science influences our beliefs and behaviour, but the process is not always with the speed envisaged by scientists. [Read more]
Editors' Choice: July/August 2017The failure of African Bank was a shock to South African markets and introduced significant systemic risk in the financial system. Could this risk have been highlighted earlier and was there a way to avoid this outcome? Sanderson and colleagues applied option valuation techniques to assess whether the markets warned of a possible African Bank failure. [Read more]


May/June 2017

Editori's Choice: May/June 2017Continued investment in promoting multidisciplinary research through national research programmes such as SANAP – the South African National Antarctic Programme – is essential for South Africa to remain globally competitive in the region to our south – a key geopolitical region. Antarctica, the sub-Antarctic islands and surrounding Southern Ocean are regarded as one of the planet’s last remaining wildernesses. [Read more]
Editor's Choice: May/June 2017Young men from poor socio-economic areas are most at risk of blunt force homicide in Cape Town. Clark and colleagues examined over 15 000 autopsy reports from a five-year period (2010–2014) from Salt River Mortuary in Cape Town’s West Metropole. The prevalence of blunt force homicide during this time was 5.32% – comparable with other regions in South Africa. [Read more]
Editor's Choice: May/June 2017Cape snoek – often seen as a low-value fish – is a healthy and inexpensive food that is high in protein and omega-3 fatty acids and low in fat. Cape snoek is a popular food choice among poorer and working-class households in the Western Cape and is prepared in several ways, from smoking to oven baking, microwave cooking to braaing. [Read more]
Editor's Choice: May/June 2017 Policymakers should look to social norms interventions as a cost-effective tool to address key public health issues in South Africa. Ganz and colleagues propose that such interventions have widespread and significant potential to address issues of public health in South Africa. [Read more]
 Editor's Choice: May/June 2017 The MeerKAT telescope – a precursor to the Square Kilometre Array – will rely on optical fibres to link the telescope receivers to a central processor point. MeerKAT requires highly accurate and stable clock distribution over up to 12 km of optical fibre to remote dishes. The clock distribution is required for digitisation of astronomical signals and instrument control. [Read more]


March/April 2017

Mathematics and...

The concept of zero is probably one that affects our lives daily, but have you ever wondered where it originated? Engagements of a mathematical nature date back to antiquity in many different parts of the world, yet today the value and potential of mathematics is not fully recognised. This potential through interdisciplinary collaborations among the mathematical sciences was explored in a recent workshop entitled ‘Finding Synergies in the Mathematical Sciences’ hosted by the Academy of Science of South Africa (ASSAf). Adler, Reddy, Hofmeyr, Wittenberg and Nongxa explored the synergies between mathematics and those fields. [Read more]

The unsolved case of Little Foot’s ageLittle Foot cannot be more than 2.8 million years old, according to Kramers and Dirks. This age differs from that reported previously by Granger et al. (Nature 2015;522:85–88) of 3.67±0.16 million years. Interpreting the ages of hominin fossils is very important for understanding the timeline of human evolution. Little Foot is a complete Australopithecus skeleton, found in 1997/1998 in sediments of the Silberberg Grotto in the Sterkfontein Caves. [Read more]
Vumba and ubumba: Traditional cosmetic clays characterisedHigh levels of quartz – of up to 85% – were found in two traditional cosmetic clays, suggesting that their use may pose a potential health risk as there is evidence of carcinogenicity at levels above 15%. The clays also contained low levels of chromium and the heavy metals copper, zinc and nickel, but were otherwise free from toxic elements. The two clays – which bear similar names in two local languages (vumba in Tshivenda and ubumba in isiZulu) – are applied topically for cosmetic purposes by the respective indigenous peoples. [Read more]
The first chemical weapons: Origins of hunting poisonsWhen did people start using poisoned arrows to hunt prey? Wooding and colleagues present a method that can accurately identify plant-based toxins present on archaeological artefacts as well as other unique chemical markers that may allow chemists to infer the presence of toxic plant ingredients applied to ancient weapons. Accurately identifying remnants of ancient poisons is a challenging task, as organic molecules are subject to degradation over time and seldom resemble their parent compound. [Read more]


January/February 2017

Editor's Choice: January/February 2017Targeting athletes’ self-awareness may have benefits for improving their mental toughness and enhancing competitive performance outcomes. In the highly competitive sporting environment, mental toughness is often considered the mental edge that underpins sporting success. With interest growing in how athletes’ mental toughness can be changed, Cowden explored whether competitive tennis players who are more self-aware tend to be mentally tougher. [Read more]
Editor's Choice: January/February 2017Stormwater harvesting can improve water security in South Africa’s urban areas. The ongoing drought in South Africa has left many parts of the country with extremely limited access to water. If a future water crisis is to be averted, the country needs to conserve current water supplies, reduce its reliance on conventional surface water schemes, and seek alternative sources of water supply. [Read more]
Editor's Choice: January/February 2017Targeted policy initiatives aimed at enhancing household income are important in the Eastern Cape, Limpopo and KwaZulu-Natal Provinces – the provinces identified as the poorest in South Africa. Households in traditional and urban formal areas diversify income sources – with up to four income sources – to a greater extent than households in urban informal and rural formal settlements in these provinces. [Read more]
Editor's Choice: January/February 2017The Klip River system – a natural wetland southwest of Johannesburg – is vital to the region’s water supply, through sequestering contaminants that would otherwise enter the Vaal River system and cause widespread pollution. Humphries and colleagues found considerable enrichments in toxic metals observed within the Klip River peats – thus highlighting the value of this system in sequestering metals from polluted water. [Read more]
Editor's Choice: January/February 2017South Africa’s higher education system stands yet again at a critical crossroad. A ‘twin’ investment strategy is required on the part of the State to remove both financial obstacles and academic obstacles that prevent the best products of our public and private schooling from successfully graduating. The student protests of 2015/2016 have put a sharp spotlight on the issue of fees and the unaffordability of tertiary education for the majority of our best qualified matriculants. [Read more]

November/December 2016

Cytotoxic activity of marine sponge extracts from the sub-Antarctic Islands and the Southern Ocean

Compounds isolated from eight species of marine sponges collected from around the Prince Edward Islands in the Southern Ocean have shown potential against cancer cells. During the 2015 annual relief voyage on board the SA Agulhas II, a team of scientists from the University of Cape Town, Rhodes University, the South African Environmental Observation Network and the Department of Environmental Affairs collected marine sponges from various depths around the sub-Antarctic Prince Edward Islands in the Southern Ocean. [Read more]

The phenomenon of skin lightening: Is it right to be light?Stricter product testing, industry compliance and greater public awareness are needed to curb the sale of harmful skin lightening products. Despite warnings based on scientific evidence that the majority of these cosmetic products found at local markets contains compounds that can irreversibly damage the skin, sales continue unabated. In spite of legislation banning harmful ingredients such as hydroquinone and mercury in cosmetics in South Africa, they are still present in widely available products. [Read more]
A spatio-temporal analysis of fires in South Africa

Global climate change will result in an increase in the frequency of fires in South Africa. Although fire activity in South Africa is in part driven by human activity, increased air temperatures and events such as La Niña have a marked effect on fire activity. Strydom and Savage investigated the spatial and temporal variations of fires in South Africa using satellite-derived data to map fire activity over the last decade. [Read more]

Characterisation of smectite-rich clay soil: Implication for groundwater defluoridation

Smectite-rich clay soil sourced locally has potential for removal of fluoride in groundwater. Research is ongoing to find an effective and sustainable method for removal of fluoride from groundwater. Groundwater is a widely used and affordable source of drinking water in most rural areas in South Africa with no centralised water supply, but some groundwater contains fluoride at concentrations above recommended levels. [Read more]

Sex and gender transformation in AfricaScientific studies on LGTBI are not only helpful but essential to improving our understanding of humanity. Transdisciplinary research is needed – not to pathologise or justify diversity – but to establish reasons for the prejudices that exist in Africa and to devise a scientific approach to changing the thinking to align with the values of the Constitution of South Africa. [Read more]

September/October 2016

A snow forecasting decision tree for significant snowfall over the interior of South AfricaSnow is rare over the highly populated metropolises of the interior of South Africa, but when it occurs, it can cause widespread disruption to infrastructure and even loss of life. Because of the rarity of snow over the interior of South Africa, inexperienced weather forecasters often miss these events. Stander and colleagues therefore developed a technique to forecast these rare snow events over the relatively lower elevations of the interior of South Africa, using the snowfall event of 7 August 2012 as a case study. [Read more]
New light on vitamin B12: The adenosylcobalamin-dependent photoreceptor protein CarHThe X-ray crystal structure of a novel light-detecting protein in certain bacteria was reported in 2015 – the International Year of Light. Chemaly describes the action of this protein in controlling the regulatory switch for the production of carotenoids (the yellow–red pigments) which protect the bacteria from the harmful effects of light, such as the production of free radicals. The protein uses coenzyme B12, which contains a light-sensitive cobalt-carbon bond, to detect visible light. The breaking of the cobalt-carbon bond changes the conformation of the protein, which then triggers the regulatory switch that allows transcription of DNA for synthesis of enzymes needed for carotenoid production. [Read more]
San and Nama indigenous knowledge: The case of |nhora (Pteronia camphorata) and its medicinal useAn important – but hitherto unidentified – San and Nama medicinal plant known as ǀnhora has been botanically identified for the first time by Hulley and colleagues as Pteronia camphorata (Family: Asteraceae), an aromatic shrub endemic to the western and southern coastal region of South Africa. Hulley and colleagues present quantitative data on the traditional knowledge associated with the plant, as well as scientific evidence, including chemical composition of the volatile oil and antimicrobial activity, to validate the traditional uses of this plant, which include the treatment of colds, influenza and tuberculosis. [Read more]
The Marine Protected Areas debate: Implications for the proposed Phakisa Marine Protected Areas NetworkRobust debate about ocean protection targets is valuable, but, according to Sink, uncertainty should not delay implementation of critical protection as South Africa speeds up ocean development to ensure greater benefits from our ocean economy. Sink discusses the proposed Phakisa Marine Protected Areas (MPA) Network in the context of a recent formal debate on the expansion of MPAs. The proposed Phakisa (MPA) Network – a unique initiative developed through Operation Phakisa Oceans Economy with participation from 17 ministries – aims to support the development of a sustainable oceans economy in South Africa. [Read more]
South Africa in the Antarctic Circumnavigation Expedition: A multi-institutional and interdisciplinary scientific project

65 years after the last research ship circumnavigated Antarctica in 1950/51, 55 scientists from 30 countries are preparing to embark on the Antarctic Circumpolar Expedition (ACE) – a 3-month cruise around Antarctica for the purposes of oceanographic research. 100 proposalswere received in response to the call for proposals and 22 projects were selected to participate in the expedition, of which only 1 South African projectwas selected – the only project from Africa: ‘A multidisciplinary, multi-resolution approach to understanding nutrient cycling and microbial diversity in changing Subantarctic ecosystems’, to be led by Dr Sarah Fawcett of the Department of Oceanography at the University of Cape Town. 7 collaborative projects led by other countries involve South African participation. [Read more]

 SEAmester – South Africa’s first class afloat In July this year, 41 students from 15 South African universities joined 20 lecturers and senior researchers on board South Africa’s first floating university – a 10-day cruise into the Indian Ocean on board the SA Agulhas II. This cruise formed the inaugural ‘SEAmester’ programme supported by the Departments of Science and Technology (DST) and Environmental Affairs (DEA). SEAmester combines intensive classroom lectures with oceanographic hands-on deck training while working side-by-side with senior marine specialists. [Read more]


July/August 2016

Archiving South African digital research data: How ready are we?According to Koopman and de Jager, the solution to long-term data security in a rapidly changing digital environment is permanent funding and training. Koopman and de Jager explored the state of data management and archiving in one department at a research-intensive university in South Africa and found that although researchers were engaged with data preservation – 88% of researchers agreed that their data should be made available for future research – neither researchers nor the university had implemented systematic research data management. [Read more]
Diverse diets of the Mio-Pliocene carnivorans of Langebaanweg, South AfricaThe giant extinct African bear was likely capable of consuming high levels of both flesh and bone. Hartstone-Rose and colleagues evaluated the dietary specialisations of this extinct species as well as those of other fossil species found at Langebaanweg – an important palaeontological site located a short drive from Cape Town – based on their dentition. Hartstone-Rose and colleagues also found that most Langebaanweg carnivorans had premolars that were less sharp than those of their modern counterparts, indicating greater bone crunching than flesh slicing specialisation. [Read more]
The stable isotope setting of Australopithecus sediba at Malapa, South AfricaImmediately before the type fossils of Australopithecus sediba were washed down the cave in a mixture of sand, mud and water, thin layers of flowstone were forming at the bottom of Malapa Cave. Both the flowstones and the fossils were deposited during a short period of instability in the earth’s magnetic field, almost 2 million years ago. This coincidence in timing allowed Holt and colleagues to reconstruct the landscape at the time of A. sediba, using stable isotopes of carbon and oxygen locked in the flowstone layers. [Read more]
Developmental simulation of the adult cranial morphology of Australopithecus sedibaAt present, only a single, juvenile, cranium (MH1) is assigned to the new species Australopithecus sediba. Although some researchers have suggested that a considerable amount of morphological change might have occurred in the cranium had MH1 lived to maturity, to the extent that it might influence existing interpretations of the fossil, Carlson and colleagues have confirmed that these changes would not have significantly altered the morphology of MH1. [Read more]
Osteogenic tumour in Australopithecus sediba: Earliest hominin evidence for neoplastic diseaseAn international team of researchers have identified the oldest tumour in the human fossil record – an osteoid osteoma, found in the vertebrae of Australopithecus sediba, from the site of Malapa, dated to almost 2 million years ago. [Read more] A second discovery – that of a foot bone of an unknown hominin species dated to 1.7 million years ago from the site of Swartkrans (also in the Cradle of Humankind) – shows definitive evidence of malignancy with osteosarcoma, a primary bone cancer. [Read more]


May/June 2016

Does the DHET research output subsidy model penalise high-citation publication? A case study The Department of Higher Education and Training’s model to subsidise universities based on research publication output may be inadvertently penalising high-citation publications. Harley and colleagues therefore recommend a revision of the current subsidy model to include a weighting for research impact. The nature of the subsidy model is such that co-authorship with other institutions reduces a university’s subsidy. [Read more]
Multimodal spatial mapping and visualisation of Dinaledi Chamber and Rising Star CaveThe fossil chamber in which Homo naledi was found is accessible only through a near-vertical narrow chute – which presented immense practical and methodological limitations on the excavation and recording methods that could be used. Kruger and colleagues thus developed and employed a multimodal set of recording and survey methods. Mapping and visualisation of the cave system, both above and below ground, were achieved by use of high-resolution laser scanning and photogrammetry. [Read more]
Climate change threats to two low-lying South African coastal towns: Risks and perceptionsCoastal towns are prime attractions for tourists, particularly in countries with favourable climate, but a study by Fitchett and colleagues indicates considerable threats of flooding to many of the beachfront properties in two local towns by 2050. These towns – St Francis Bay and Cape St Francis – have thriving tourism sectors comprising small accommodation establishments and an array of outdoor activities. [Read more]
Citizen science tools available for ecological research in South AfricaSouth Africa is host to many citizen science projects that simultaneously address important research questions while providing opportunities for outside-of-the-classroom learning. According to Hulbert, citizen science tools enable the coupling of science education and hypothesis-driven research. Citizen science projects offer opportunities for all citizens to participate in and contribute to research projects. [Read more

March/April 2016

Recent trends in the climate of Namaqualand, a megadiverse arid region of South AfricaFuture increases in temperature over the Namaqualand region could create conditions unsuitable for some endemic species and are likely to have considerable implications for heat stress in livestock. According to Davis and colleagues – who studied trends in the climate across Namaqualand over the last 30 years – both temperatures and the frequency of hot extremes have increased across the region. [Read more]
Trading on extinction: An open-access deterrence model for the South African abalone fisheryMuch of wildlife management in southern Africa is based on the adage: ‘if wildlife pays, it stays’. With authorities selling confiscated abalone (Haliotis midae) on the legal market, the same applies to abalone. Crookes developed a model for the abalone fishery in Table Mountain National Park in which the marine authority attempts to maximise revenues by varying the level of preventative enforcement. [Read more]
Treatment technology for brewery wastewater in a water-scarce country: A reviewThe brewery industry is one of the largest users of fresh water. The average water usage by SABMiller – the world’s second largest beer producer – is reported to be about 4.6 L of water to produce 1 L of beer. Jaiyeola and Bwapwa reviewed current treatment methods and recommend that the brewery industry view the effluent as a commodity rather than as waste and invest in developing alternatives for its treatment. [Read more]
Antimutagenic and antioxidant effects of a South African traditional formulation used as an immune boosterDespite existing legislation, the traditional medicines sector in South Africa is largely unregulated. Traditional medicines should be scientifically validated in order to contribute to advancing traditional healing. uMakhonya®a commercially available traditional immune stimulant – showed promising antioxidant activity in a study by Ngcobo and colleagues. [Read more]

January/February 2016

Radiological and genetic analysis of a Late Iron Age mummy from the Tuli Block, BotswanaRühli and colleagues report the first successful extraction of ancient DNA from a southern African mummy – the first mummy reported from the Tuli region in northern Botswana. Mummified human remains are valuable sources of information on past populations but are rare finds in southern Africa. [Read more]
Safe spending rates for South African retireesSouth African retirees who spend more than 5% of their initial capital per annum could deplete their retirement capital. US financial advisors advocate a safe 4% withdrawal rate, but inflation in the USA is far lower than that in South Africa. Adjusting for inflation, Maré determined an ‘optimal’ spending rate for retirees who invest in a combination of domestic South African equities and fixed interest bearing securities (such as bonds). [Read more]
Responses of African elephants towards a bee threat: Its application in mitigating human–elephant conflictBees could be the solution to mitigating human-elephant conflict. Human-elephant conflict occurs when elephants raid crops and destroy property and is common in areas where population and elephant ranges overlap. Ndlovu and colleagues investigated whether buzzing bee noises and/or honey scent (as surrogates for live bees) could be used to effectively deter elephants. [Read more]
Indicative hazard profile for strong winds in South AfricaWind hazard, and consequently the risk of disaster from windstorms, varies spatially and seasonally across South Africa. The south and southeast regions of South Africa, as well as parts of the escarpment, are at greatest risk of wind hazard. Kruger and colleagues used data from the South African Weather Service’s weather stations across the country to develop a national profile of the wind hazard. [Read more]