Editors' Choice

January/February 2019

East of Still Bay on the Cape south coast of South Africa lies a rugged, remote stretch of sea cliffs that expose Late Pleistocene aeolianites (or cemented dunes). The first South African record of elephant tracks, the first rhinoceros tracks, and the first giant Cape horse tracks were recorded from two rocks in this area: Roberts Rock and Megafauna Rock. Among the fossil tracks on these rocks, Helm and colleagues have recorded track evidence of the long-horned buffalo and smaller species. Two of the species recorded are now extinct (the giant Cape horse and long-horned buffalo). These rocks provide a glimpse into Late Pleistocene dune life, and suggest an area that was teeming with large mammals. Roberts Rock has since slumped into the ocean and disintegrated – the fate of many exposed tracksites. For this reason, and because new sites frequently become exposed, regular surveying of this track-rich coastline is necessary.


Interventions aimed at improving science knowledge of learners in South Africa will continue to fail if their reading comprehension skills are under-developed. In an attempt to understand why previous science interventions for township learners had helped only some learners, Stott and Beelders assessed the relationships between learners’ reading comprehension and their Natural Science marks and improvement from intervention programmes. Using an eye tracker to observe the eye movements of learners engaging with science software, Stott and Beelder observed that the majority of learners guessed at least some answers without reading, with some avoiding any, or much, of the required reading. They found moderate to strong correlations between the learners’ inferred ability to read science texts with comprehension and both their Natural Science marks and the benefit they gained from previous interventions. The findings suggest that only top achieving township learners possess the reading comprehension skills to benefit from interventions which rely on text usage.


South Africa is intent on promoting its science, technology and innovation (STI) capabilities to achieve improved socio-economic development outcomes. Recent practical work has included the demonstration of innovations in relatively remote rural areas to encourage inclusive development in line with the National Development Plan. These innovations include water, sanitation and energy technologies, often combined with information and communication technologies (ICT). Drawing on the experiences of the multiple actors involved, Hart and colleagues identified key challenges in the demonstration process as limited beneficiary participation; haphazard needs assessments; top-down beneficiary, site and technology selection; and a lack of necessary ICT infrastructure. The process was further complicated by different priorities of national and local stakeholders, and vast distances that personnel and materials had to travel. A well-considered process of demonstration planning and implementation could reduce some of these challenges. Innovation demonstrations are an important means of first-time testing and fine-tuning innovations outside of the laboratory through which the focus is shifted from research to acceptability, usability and value. Usefulness will not simply follow because the technical aspects of the innovation have been met.


Traditional medicines should undergo testing before they are administered to patients. Traditional healing is now legally recognised in South Africa and the safety of traditional medicines is thus a priority. Madike and colleagues tested aqueous extracts of wild garlic (Tulbaghia violacea)a common plant used by traditional health practitioners to treat various ailments – and found negative effects on cell division and growth. Information about the healing properties of T. violacea is usually passed on from one generation to the next without any scientific evidence available on this plant and its potential dangers. Madike and colleagues obtained extracts from the leaves, stems and roots of T. violacea and tested the effects of different concentrations on the growth of onion cells. The effect of these extracts on onion cells is similar to what would occur in human cells. They found that high concentrations of plant extracts caused damage to the chromosomes of cells.

November/December 2018

South Africa’s science, technology and innovation policy is being updated at a time when the need to provide economic leadership is a critical imperative. The 2018 White Paper on Science, Technology and Innovation sets out the principles for the institutional, regulatory and financial architecture of the future science, technology and innovation system within South Africa. The draft document is clear on its intent: it seeks a system which is bigger, more inclusive and has greater economic impact. None of these objectives is new or controversial; the problem has been the achievement thereof. Walwyn and Cloete argue that South Africa is likely to continue to fail in these objectives unless more emphasis is placed on human capability, institutional reform, sustainability and policy experimentation. Moreover, a more convincing theory of change is needed that will persuade politicians and the public of the urgency for increased spending on research and development as a means of lifting the country out of its economic depression.

How can innovative development pathways reduce inequality and greenhouse gas emissions? Reducing inequality is our top priority in national development, while climate change is the foremost global challenge of this century. Winkler proposes that a comprehensive theoretical framework is needed to lead the way to a low-carbon high-equity future. Charting innovative development pathways requires changes in policy, technology and investment. But perhaps more fundamentally, it requires an understanding of the complex determinants and agents of change, followed by adaptive management of complex systems. Such complexity requires radically inter- and trans-disciplinary research, to inform adaptive management. Co-production of knowledge and learning by doing will be important. Young people need key skills in thinking about intervening in systems: complex problem-solving, critical thinking and creativity. What is needed is a new social contract, in which the rich live better with less, the poor are lifted out of poverty, and middle-class aspirations shift from having more to living well.


Marula vinegar produced from waste by-products was found to be a potential source of health promoting compounds including total phenolics and flavonoids with good antioxidant properties. Marula is a well-known indigenous plant in South Africa, and the fruit is used to make the legendary Amarula cream liquor. Molelekoa and colleagues investigated the feasibility of using marula fruit waste sourced from a processing plant as feedstock for vinegar (acetic acid) production. They used two fermentation techniques (surface and submerged culture methods) using both naturally occurring and inoculated bacteria. The surface culture method combined with inoculation produced a higher-quality vinegar with potential for commercial-scale production. A consumer survey recommended the application of the vinegar in products such as salad dressing and mayonnaise.


Unemployment exit rate, job sustainability and unemployment duration collectively affect the persistence of unemployment. Modelling the relationships among these factors is recommended for finding solutions to unemployment issues. Nonyana and Njuho explored the benefits of using econometric models in unpacking features of unemployment in South Africa. Using these models they found that unemployed people in South Africa tend to have lower unemployment exit rates; which relates to job scarcity in the labour market, whilst available jobs are less sustainable and the bulk of those who are employed are likely to lose their jobs within a year. Unemployment duration featured as a structural factor that has a considerable impact on unemployment: the longer the unemployed remain unemployed, their prospect of finding employment deteriorates.


Tropical cyclone Dineo made news headlines across southern Africa in early 2016, although it was only a category 1 storm. Tropical cyclones are devastating storm systems, characterised by strong winds, heavy rainfall and storm surge flooding in coastal areas, and are classified according to intensity from category 1 (mild) to category 5 (devastating). Since 1994 – when the first tropical cyclone in the South Indian Ocean intensified to category 5 status – the number of category 5 storms in the South Indian Ocean has increased steadily each decade. Fitchett has found that the incidence of a category 5 tropical cyclone, and subsequent increase in frequency of these highest intensity storms, appears to be linked to ocean warming, as sea surface temperatures of 27–29°C are being experienced progressively further south. Category 5 storms have been recorded for the North Atlantic Ocean since 1924, but were not a feature of the South Indian Ocean for many decades.

September/October 2018

Antibiotic resistance is a threat to South Africa’s healthcare system, for which there is an urgent need to enforce legislation on drug distribution and usage, to prioritise the use of alternatives to antibiotics and, finally, to implement a nationwide effective antimicrobial resistance surveillance system. Tatsing Foka and colleagues reviewed the incidence of vancomycin-resistant enterococci in South Africa. The recent and continuous detection of a high level of vancomycin-resistant enterococci in a variety of South African ecological niches is a serious public health concern, especially given the high incidence of immunocompromising complications such as HIV/Aids in the country. Agricultural practices coupled with the misuse of antibiotics in intensive animal rearing and hospital facilities have been identified as the main cause for the development of resistant strains in South Africa, and the world at large. The health implications of vancomycin-resistant enterococci and their resulting economic burden on our healthcare system cannot be underestimated. Although tremendous efforts have already been made in South Africa to tackle antimicrobial resistance issues, and vancomycin resistance problems in particular, results from recent studies need to be incorporated into fully modified operational policies.


Nnadih and colleagues report the first ground-based recorded observations of sprites over South Africa. Sprites – named after the characters in Shakespeare’s The Tempest – are electrical discharges in the mesosphere above an active thunderstorm that are powered by large lightning strikes, but are rarely visible from the ground. Sprites have been studied extensively in other continents, but despite Africa being a lightning-rich continent, there is little or no active sprite-related research in Africa. Their study enables us to understand the interconnected processes of atmospheric electricity and terrestrial weather. The phenomenon was reported anecdotally in Johannesburg in 1937, but Nnadih et al.’s report is the first record of sprites in southern Africa. On 2 of 22 nights of observations, they recorded about 100 sprite elements from Sutherland in the Northern Cape, comprising different morphologies (55% were carrot-shaped sprites). The sprites were triggered by positive cloud-to-ground lightning strikes and were observed from distances of between 400 and 800 km. These first ground-based observations, which suggest that the optical intensity of sprites is proportional to the lightning stroke current, will pave the way for a more comprehensive study of sprites in South Africa.


The goal to end AIDS as a global pandemic by 2030 is threatened if, as this study suggests, one-third of adults presenting for HIV counselling and testing at healthcare clinics in South Africa come from households with insufficient food. In a study of over 2700 adult women and men presenting for HIV testing at three public sector healthcare clinics in eThekwini (Durban metropolitan region), Nyirenda and colleagues found that individuals from food-insecure households were more likely to test HIV positive than those from food-secure households. Although the reason for this association was not evident, the results highlight that many newly diagnosed HIV-positive individuals do not have enough to eat. Their findings support the need for socio-economic and structural interventions to transform food-insecure into food-secure households. Failure to do so urgently in high HIV endemic areas like KwaZulu-Natal, South Africa, is likely to seriously challenge the attainment of global targets such as the UNAIDS’ 90-90-90 goal.


Local journals face a difficult task: escaping the ‘impact factor trap’ by attracting good research away from international journals; a task which will be made impossible by graded national financial incentives. Although the Department of Higher Education and Training does not differentiate between national and international publications with respect to subsidy for journals on accredited lists, some local universities award a higher proportion of the subsidy to authors who publish in international journals. There is pressure throughout academia to publish in high impact factor journals. The Scimago Journal Rank is an index that ranks journals based on impact and prestige, partly by measuring from where citations come. Lee and Simon examined 23 000 journals listed in the Scimago database, which included only 82 South African journals. They argue that this index is not suitable for Africa, as journals with Africa in their title are ranked lower than other journals by this index. They assert that African journals have not yet had the time required to gain the same prestige, as historically they have had low visibility. Applying incentives based on Scimago Journal Rank will therefore disadvantage local journals.

July/August 2018

Awareness campaigns alone may not be sufficient to reduce the number of accidents on South African roads. Introducing compulsory third-party insurance and the imminent emergence of self-driving cars may have an impact. According to Fourie and Verster, human factors contributed to almost 80% of the fatal road accidents in South Africa in 2015, with road and environmental conditions contributing to 13% and vehicle factors to 8%. Fourie and Verster analysed the fatal road accidents – those in which at least one person is killed as a direct result of the accident – in South Africa in 2015. Although fatal accidents constituted only 1.3% of all road accidents, they equated to 42% of the total costs involved. The economic cost – R143 billion in 2015 – is not the only cost: 13 000 lives were lost in 2015 as a result of road accidents. Pedestrians accounted for 38% of the fatalities and male individuals 78%, with 41% of those killed being younger than 30 years old.


Bt modification in maize does not affect non-target beneficial microorganisms such as endophytes. Although Bt maize is one of the most popular GM crops in the world, little is known about potential impacts on ecosystem functionalities. Genetically modified Bt maize contains a gene from the soil bacterium Bacillus thuringiensis (Bt) which provides resistance to major insect pests. Mashiane and colleagues investigated whether genetic modification affected non-target microorganisms such as endophytic bacteria which are important in agriculture. Maize is one of the most important crops in the world – it is consumed as a staple food and as animal feed in both developing and developed countries. Bacterial endophytes from two developmental stages of both Bt maize and its isogenic parental line were screened for their capabilities to participate in plant protection, nutrient mobilisation as well as production of a plant growth hormone. Interestingly, Mashiane and colleagues found that growth stage rather than genetic modification had a significant impact on the endophytes and their functions.


Efforts to improve performance in science should also focus on developing non-cognitive aspects such as self-efficacy. A person’s motivation and confidence can make seemingly impossible tasks possible. This self confidence in one’s ability (self-efficacy) extends to performing science-related tasks in the classroom. The strength of this belief has an impact on behaviour – those who have higher self-efficacy are more likely to persevere in an activity, no matter how difficult, until they succeed. Using information from 12 500 Grade 9 students in South Africa, Juan and colleagues found a positive relationship between self-efficacy and science achievement. In addition, positive student–parent and student–teacher interactions were related to increases in students’ science self-efficacy. Of concern was the finding that girls reported lower self-efficacy than boys, even when they scored the same on the science assessment.


South Africa nearly doubled its R&D expenditure in social sciences and humanities research fields between 2005 and 2014, outpacing countries such as Russia, Turkey and Uruguay. A closer look at the data, however, suggests that R&D expenditure was mainly concentrated in a few research fields – finance, economics, education, accounting and political science. Intense global environmental and technological changes, coupled by critical levels of poverty and inequality in South Africa, are key urgencies that science policymakers face in the development of the new White Paper on Science, Technology and Innovation. Within this context, the case for advancing the social sciences and humanities in South Africa could not be more urgent and compelling; although questions remain as to where to target strategic R&D investments for meaningful socio-economic and epistemic impacts. Molotja and Ralphs argue that institutional R&D planners and national policymakers need to better balance current priorities and future needs if R&D in the social sciences and humanities is to be leveraged for larger socio-economic impacts, as envisaged by the new draft White Paper on Science, Technology and Innovation.


The global knowledge economy continues to be dominated by the Global North. Reasons may include a lack of proper national government support and funding and academic prowess on the part of scholars in the Global South. However, focusing on only these largely technical and economic reasons, whilst ignoring the greater cultural and political reasons within which the practice of academia is in itself deeply entrenched, limits our understanding. Dalu and colleagues consider the barriers that stem from the practice of the ‘old boys’ network’ as a possible contributor to Global South academic performance in the global knowledge economy. They contemplate the idea of monopolies of power centred in the Global North with regard to who moderates academic outputs, and how the Global South continues to uphold the standards of academic outputs as they are stipulated in the Global North. Knowledge exchange platforms between the Global North and South have developmental implications within the decolonisation agenda currently on the South African table.


May/June 2018

Did Cape Town’s water crisis happen because the city’s leadership thought that they lived in Europe? More generally, does the practice of applied sciences like engineering adequately reflect the South African context? These questions offer practical perspectives on the contentious debate about the decolonisation of our universities and society. There is plenty of evidence that civil engineering initially served the colonial purpose of extracting wealth; and that the exclusion of black people from the profession in South Africa and the British colonies left a legacy of damaging distrust. How can the society and its engineering professions move beyond this inheritance? As we seek an inclusive way forward, engineers must become more assertive about their role as pathfinders. They must help to engineer more effective institutions as well as physical structures and services. On the way, they will have to help politicians to learn to take advice.


Inadequate governance of groundwater harms economic growth, food security, social stability, land reform, transformation and other sectors. Mahikeng, the capital of North West Province, depends on groundwater from nearby aquifers for more than half of its water supply, but falling groundwater levels have made this water supply less predictable and less reliable. According to Cobbing and De Wit, the groundwater aquifers near Mahikeng – if they were better managed – could help to make Mahikeng’s water supply more reliable, and less vulnerable to drought. The natural environment would also benefit, as would social stability and business confidence. The root of the problem is poor cooperation between those extracting and those controlling the groundwater, including farmers and the municipality. An undesirable “Nash” equilibrium has emerged, meaning that all the parties are currently losers. However, this sub-optimal equilibrium can be broken – there is enough water to go around, and “win-win” outcomes are possible. But the hidden cost of today’s poor management is high.


South African researchers contribute more than 3% of the global literature on mammalian behavioural ecology, with a strong focus on the broader themes of mating, social and foraging behaviour. The large number of protected areas and mammalian guilds in South Africa provide unique opportunities for the study of behavioural ecology – a sub-discipline of zoology that has evolved and grown significantly since the start of the 20th century. Researchers link behaviour to genetics, evolutionary trends, and fast adaptation to a rapidly changing world. Le Roux reviewed over 1000 papers published from 2000 to 2015 and determined the South African contributions to this multidisciplinary field. Although South African researchers contribute more than 3% of the global literature, some important themes within behavioural ecology – such as animal cognition and personalities – that are gaining rapid international traction are not studied locally.


Food waste in South Africa is lower than that in Europe but greater than in the rest of sub-Saharan Africa. Households in South Africa dispose of less food into the municipal bin than European households do, but more than households in the rest of sub-Saharan Africa, excluding food fed to pets or disposed of onto compost heaps at home. Food waste is an important issue in light of population growth and global food security concerns. It is estimated that between a third and half of all food produced globally is wasted every year while 12 million people in South Africa go to bed hungry each day. Oelofse and colleagues measured the actual amount of food waste disposed of into municipal bins by households in the City of Johannesburg and Ekurhuleni. The food disposed of amounts to 12 kg per person per year in Johannesburg and 8 kg in Ekurhuleni – a contribution of about 51 000 tonnes in Johannesburg and 25 000 tonnes in Ekurhuleni to the municipal solid waste disposed of on already stressed landfills.

March/April 2018

Cole et al. propose additional indicators for SDG 6 – Sustainable Development Goal 6, namely “Water and sanitation for all” – on water efficiency that focus on how individuals and households benefit from allocations and the use of water resources. Appropriate indicators can support decision-making and highlight key issues on inequality, unemployment and sustainability. Water is fundamental – not just for human well-being but also for economic growth. In a water scarce country like South Africa, it is important to understand how the allocation of water resources is directly and indirectly benefitting individuals, households and the economy. Cole and colleagues analysed water use and water-dependent jobs across 42 towns in the Berg Water Management Area, in the southwest corner of South Africa and found significant variation across industries and municipalities, highlighting the impact of water allocation on the local population and economy. In the face of growing demand and uncertain supply, future water allocation decisions require better water-use and employment data, spatial analysis, scenario development and stakeholder engagement.


The Square Kilometre Array South Africa (SKA SA)’s success is underpinned by open and inclusive institutions, fostering and leveraging interrelationships, promoting innovation that may be commercialised, and attracting, retaining and training suitable individuals. These four themes or key pillars (institutions, interrelationships, innovation and individuals) – comprising the 4I model – were revealed to be crucial for engendering a knowledge economy. Bhogal developed the 4I model whilst exploring factors that inhibit and enable the impact of SKA on South Africa’s knowledge economy. Increasingly, nations pursue knowledge-based endeavours to promote economic growth. SKA SA – South Africa’s flagship science project and the world’s largest radio telescope – is expected to develop local competitive advantage, which will contribute to economic growth. Sub-themes in the 4I model include the role of a nation’s inherent competitive advantage in informing its competitive and innovation strategy, multidimensional interrelationships and politically astute leadership. A deeper understanding of the 4I model forms a basis for strengthening each pillar and thereby its impact on the knowledge economy.


Recently discovered Australopithecus sediba is known from only one time and place: Malapa, South Africa, dated to ~800 thousand years later than the earliest fossils attributed to the genus Homo – fuelling debate about whether A. sediba could be ancestral to Homo and modern humans. Because the fossil record is incomplete, researchers cannot be certain how far back in time any species extended. However, by reviewing evidence from other, better documented hominin species, Robinson and colleagues have demonstrated that dates alone are insufficient to reject the hypothesis of direct ancestry of Homo as, on average, fossil hominin species lived for almost one million years. Using the one date for A. sediba as a first, middle or last date of appearance, Robinson and colleagues compared possible temporal ranges of A. sediba and Homo for known modes of speciation, and showed that the possibility of A. sediba being ancestral to Homo could not be precluded. Until additional data are available for the temporal range of A. sediba, any inferences about the evolutionary relationship between A. sediba and Homo should be based primarily on morphology.

Age, experience and income affect users’ perceptions of online banking in South Africa. The adoption of online banking by South Africans has been very low compared with the global average. Mujinga et al. investigated if online banking usability was a barrier to adoption using a system usability measurement tool and found that assessment of usability was affected by age, experience and income – with older, more experienced and higher income users scoring usability more highly. Gender, employment, and use frequency had no impact on users’ assessment of online banking. Banks make large investments in providing self-service solutions. To realise returns on these investments and to reduce operating costs for in-branch services, clients must use the online services offered. An in-depth investigation is needed to identify usability factors that might be contributing to the lack of uptake of online banking services in South Africa.

January/February 2018

Did ancient giraffes once roam a savanna now submerged by the Gouritz and Breede Rivers? The recent discovery in 2016 of fossil giraffe tracks east of Still Bay on the Cape south coast – the first Pleistocene fossil giraffe tracks to be recorded in southern Africa – significantly increases the geographic range of this species. Until now there have been no reliable historical or fossil records for the giraffe south of the Orange River or northern Namaqualand. Based on correlations to dated sites nearby, the tracks were probably made around 125 000 years ago. Helm and colleagues report on the discovery which has implications for Late Pleistocene climate and vegetation in the southern Cape, because of the specialised feeding niche of giraffe populations. Evidence suggests that the currently submerged floodplains of the Gouritz and Breede Rivers supported a productive savanna during Pleistocene glacial conditions. This habitat would have been suitable for giraffe, and would likely have allowed giraffe to migrate along the southern coastal plain.

An assemblage of hominin fossils from Dinaledi Chamber, attributed to at least 15 individuals of the newly identified species Homo naledi, is strikingly different from australopith and Neanderthal sites with multiple individuals. The difference lies in the high proportion of infants and young juveniles in the Dinaledi assemblage as well as in the location of the Dinaledi fossils, which are scattered within a hidden cave chamber. About 1550 fossil specimens of a single hominin species were recovered from the Dinaledi Chamber (Cradle of Humankind, South Africa) during excavations in 2013–2014. Bolter and colleagues used 190 dental elements to identify life-history stages and attributed these elements based on their degree of development to 15 individuals: 9 immature and 6 adult individuals, including one old adult with very worn teeth. Adults were classified by sets of dentition with all the permanent teeth in place; infants (3) as those with only deciduous (or baby) teeth, juveniles (4) as those with a combination of deciduous and permanent teeth, and sub-adults (1) as those with permanent teeth that were not fully erupted. One immature individual could not be assigned to an age class. Current studies using forensic techniques are proceeding to match skeletal bones with the dental remains. The Dinaledi assemblage presents an uncommon opportunity to examine a fossil species at the population-level perspective. Additional excavations underway suggest more individuals lie in wait deep inside the cave system.

The fossilised skull of an Australopithecus africanus from Sterkfontein – well known as “Mrs Ples” – may indeed be a “Mr Ples”. Evidence obtained from an ongoing study of canine sockets and skull measurements supports the view that “Mrs Ples" is probably a small male individual. Both age and sex are factors that contribute to variation in growth and development of the cranium in australopithecines. On the basis of their comparisons of alveolar canine dimensions, Tawane and Thackeray conclude that “Mrs Ples” is the skull of a small male rather than a large female individual. The fossil is the most complete cranium of A. africanus and was discovered at the Sterkfontein Caves in the Cradle of Humankind in 1947 by Robert Broom and John Robinson. Broom claimed that it represented a female individual on the basis of canine sockets, but he did not have a large comparative sample of specimens to allow him to support this opinion. Within the last 70 years, more hominin fossils have been obtained from Sterkfontein. The view that "Mrs Ples" is a female specimen of A. africanus has been highly controversial and the skull continues to be the subject of research in the context of human evolution.

Termites are a food source with high economic and social importance and the preservation of the indigenous knowledge used during the harvesting and processing of termites should be prioritised. Netshifhefhe and colleagues surveyed over 100 harvesters, marketers and consumers from 48 villages in the Vhembe District Municipality of Limpopo Province, South Africa. Three termite species of the Macrotermes genus – mound-building termites which dominate the African savanna – are consumed, with M. falciger being the species of preference (90% of all termites). Individuals of all ages consume termites and the method of preparation preferred (by 78% of respondents) is frying. Termites are rich in proteins, fats, vitamins and many essential mineral nutrients. In addition to providing food security, income from the sale of termites can be as much as ZAR18  000 per year, and thus contributes significantly to the livelihoods of many rural families.

November/December 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]



Rudman 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]



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]



Most 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]



In 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

Recent 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]



Using 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]



More 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]



A 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]



DNA 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

Science 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]



Extreme 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]



Women 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]



Containing 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]



The 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 2017

Continued 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 2017

Young 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 2017

Cape 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 age

Little 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 characterised

High 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 poisons

When 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 2017

Targeting 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 2017

Stormwater 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 2017

Targeted 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 2017

The 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 2017

South 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]