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Innovative "invisible ink" detects TB

- Wits University

Scientists have pioneered a process to detect TB bacteria by adding a molecule to the bacteria's own armour that lights up under fluorescent light.

In a paper just published in Science Translational Medicine, authors report that Mycobacterium tuberculosis (Mtb) specifically can be detected with a flourogenic trehalose analog. 

This analog, a new stain called DMN-trehalose[1], lights up only inside living TB bacteria, which mitigates the time-consuming process of washing usually required to reveal bacteria.

Patients with TB can now be more accurately and quickly diagnosed and treated.

“Where we’re positioning the new stain is to create a simpler process, which provides the opportunity to stain TB bacteria in a smear more quickly and with high specificity,” says Professor Bavesh Kana, Head of the Centre of Excellence in Biomedical TB Research at Wits and co-author of the paper.

TB bacteria have traditionally been detected in three ways: 

  1. Sputum [saliva] smear staining microscopy
  2. Culturing [growing] tubercle bacteria in a laboratory, which takes up to 42 days
  3. Detection of the DNA of TB bacteria using the GeneXpert machine, which requires the machine

The new DMN-trehalose innovation aims to make smear microscopy easier to perform.

The science inside

TB bacteria are rod-shaped and have protective exterior layers – similar to a capsule that contains and protects the powder inside. One of these layers is mycolic acids, made with a molecule called trehalose, which is a fatty “brick”.  

TB bacteria use trehalose to build their own defence wall, which protects the bacteria against a person’s immunity. Trehalose is a chemical molecule that is unique to the family of organisms that contain TB bacteria.

“Mycolic acids are fatty acids and because of that, they’re waxy. They form a thick waxy coat that drugs struggle to get through – it’s like the brick. This layer protects the bacteria,” says Kana.

Mycobacterium tuberculosis are the bacteria that cause TB 

Cellular self-sabotage

The innovation involved the fusing [conjugation] of trehalose with a DMN molecule. The resultant DMN-trehalose is then fed to sputum-derived bacteria. The TB bacteria take it up and incorporate the DMN-trehalose into their own cell walls. The bacteria then light up under a microscope when illuminated with fluorescent light.

The TB bacteria cell continued to use these ‘bricks’ for its protective wall, oblivious to the adjustment to its chemical composition. 

“You know those invisible ink pens that you can’t see until you put the right light on? This is exactly like that. That’s the beauty of this – you don’t need to add anything. By the nature of its chemical properties, it lights up,” says Kana. 

DMN-trehalose was created by Carolyn Bertozzi and her team at Stanford University. Kana and Dr. Christopher S. Ealand and Dr. Julian S. Peters at Wits added the DMN-trehalose to sputum smears from TB patients in Soweto, and demonstrated that it can work for the detection of TB from patient diagnostic specimens. 

A no wash high specificity viability stain

Although existing stain processes also distinguish between TB and other bacteria, DMN-trehalose stains only live TB bacteria.

“Only live TB bacteria cells can do this [illuminate], because they have to build the DMN-trehalose into the cell wall,” says Kana.

DMN-trehalose is naturally fluorescent and solvatochromic [colour changing] and it only illuminates in the presence of specifically TB-type bacteria. The advantage is there is no background signal indicating anything other than TB-type bacteria and thus no need to wash to reveal these bacteria.

“Technically the process becomes quite simple. You take the sputum sample, incubate it with some DMN-trehalose for a couple of hours, smear it and then look at it. There’s no washing. It’s a no wash high specificity viability stain,” says Kana.

Professor Bavesh Kana is Head of the Centre of Excellence in Biomedical TB Research at Wits

Progress for TB patients

Importantly, the new DMN-trehalose stain enables monitoring a patient’s response to treatment.

A patient infected with 100 TB bacteria, for example, could expect a gradual reduction in the number of TB bacteria over six months of treatment. Existing smear diagnostic methods, however, are inadequate at demonstrating how well a person is actually responding to treatment, as these methods reveal live and dead bacteria.  

“Because DMN-trehalose only stains live bacteria, it will better indicate how well or poorly a person with TB is responding to treatment,” says Kana.

DMN-trehalose has proved effective in detecting live TB bacteria in patients. Dr Neil Martinson, co-author of the paper and Acting Director of the Wits Perinatal HIV Research Unit, collected sputum samples from patients.

“We could demonstrate [DMN-trehalose] in clinical specimens. We didn’t just do it in the lab – we went and got patients and did the smear on patients. Neil was able to help us get those patients,” says Kana.

Scientists have yet to establish whether DMN-trehalose detects living but inactive or dormant TB bacteria or Mtb that is not rod-shaped.

“We have seen TB bacteria that aren’t rod-shaped and that wouldn’t stain,” says Kana.

TB Awareness Month

Ahead of TB Awareness Month in March 2018, TB remains the leading cause of death worldwide from an infectious bacterial disease. New diagnostic modalities that are cheap and scalable in the healthcare systems of countries with a high burden of TB are urgently required. In this context, innovations such as DMN-trehalose provide a framework to use existing diagnostic technologies more effectively.


[1] Dimethylamine-napthalimide-conjugated trehalose

New study reveals the secret of magmas that produce South Africa's national treasures

- Wits Communications

Study conducted by the School of Geosciences reveals how platinum-bearing chromite layers form in the crust of the Earth.

South Africa’s history and economy has been built on its rich natural treasures of a number of precious metals, stones and minerals.

The country’s mineral deposits have been created over hundreds of millions of years through processes that are still not completely understood.

One of these processes, that has troubled scientists and geologists for years, is the origin of chromitite layers hosted by layered intrusions – a major source of chromium on our planet. This process has been a mystery for decades, as scientists tried to work out how layers of pure chromite form from magmas that are coming from Earth’s mantle. These are supposed to be rich in a mineral called olivine – not chromite. 

Professor Rais Latypov

“It has been widely believed that magmas sourced from the mantle cannot directly crystallise chromite, as the mantle rocks that are being melted are rich in olivine, and therefore these melts should crystallise olivine, not chromite,” says Professor Rais Latypov from the School of Geosciences of the University of the Witwatersrand in South Africa, whose research team published a paper in Nature Communications in 2018. 

“Together with a large group of my colleagues, I have been trying hard for several decades to find a mechanism that can explain the formation of these large chromite deposits in shallow crustal chambers but it turned out that we have been looking in the wrong place.”

To find the answer to these questions, Latypov and his team have been studying layers of chromite in South Africa’s Bushveld Complex, where over 80% of the global resources of platinum-bearing chromite deposits can be found.

They discovered that some basaltic magmas will form chromite after decompression as they rise up from the mantle through the crust towards the Earth’s surface. The reduction in pressure, as the magma rises up from the mantle to the crust, is key to the crystallisation process of the chromite.

“When these magmas arrive into a shallow magma chamber, sitting only a few kilometres below the surface of the Earth, they are already saturated in pure chromite, and, on cooling, can crystallise layers of platinum-bearing massive chromitite.

Chromium is an important industrial element that substantially improves the physical and chemical properties of steels, increasing their strength and making them corrosion-resistant. The platinum that is associated with these rocks is used in catalytic converters within cars to break down toxic exhaust gases into relatively benign species.

These zebra-striped coloured layers of platinum-bearing chromite that are formed through this process can be seen clearly in the ridges at the top of the Bushveld Complex, near Steelpoort in Mpumalanga, which became exposed through erosion over the many millions of years since they formed. Some of these layers can be several meters thick and extend for hundreds of kilometres.

“The Bushveld Complex covers an area of 100s of square kilometres. It stretches from Steelpoort in Mpumalanga in the East, past Pretoria to the Pilanesberg in the West; and from Bethal, Mpumalanga in the South to north of Polokwane in Limpopo. We believe that the Bushveld chamber must have been operating as a flow-through system into which magmas were entering and depositing their chromite, before flowing out of the chamber and erupting as basalts via volcanoes, which have now been eroded away,” says Latypov.

“It seems that the reduction of lithostatic pressure during the transfer of mantle-derived melts towards the surface plays a vital role in the formation of magmas that produce planetary resources, without which modern human society cannot develop in a sustainable manner.”

Further research is being conducted on whether other magmatic deposits around the world, such as vanadium-bearing magnetite in layered intrusions, can also be related to lithostatic pressure reduction. 

Scifest Africa 2018

- Wits University

Catch these Wits researchers at South Africa’s National Science Festival that kicks off in Grahamstown today.

South Africa’s National Science Festival, Scifest Africa, will be celebrating its 22nd anniversary event from 7 to 13 March 2018.

Themed: Innovation 4.0, Scifest is focusing on the Fourth Industrial Revolution this year; from artificial intelligence to 3D printing, nanotechnology, digital, quantum computing and the unlimited possibilities of emerging technology breakthroughs.

If you are at Scifest this year, be sure to catch these two lectures presented by Wits scientists:

Professor Lesley Cornish

Thursday, 8 March 2018: Why Should I be interested in Materials?, presented by Professor Lesley Cornish from the DST-NRF Centre of Excellence in Strong Materials in the Wits School of Chemical and Metallurgical Engineering.

Cornish holds a BSc (Metallurgy and Materials), MSc (Computer Science) and PhD (Metallurgy and Materials) from the University of Birmingham, UK. She is a Physical Metallurgist and has been working on alloy development almost continually since her PhD, at the United Kingdom Atomic Energy Authority, University of the Witwatersrand and Mintek. Her research has focused mainly on platinum-based alloys, cermets, as well as the derivation of phase diagrams. Cornish is currently supervising or co-supervising 12 postgraduate students, mainly at Wits University, with 30 MSc and 20 PhD students already graduated.

Dr Tiisetso Lephoto

Friday, 9 March 2018: Entomopathogenic Nematodes: Biological control agents to aid South African Agricultural industries, presented by Dr Tiisetso Lephoto, one of the youngest PhD graduates in the field of cell and molecular biology.

She is a multi-award winning, trailblazer scientist and has published papers in international journals. She obtained her PhD at the age of 26 in Nematology, Genomics and Biotechnology with an emphasis in Bioinformatics at the University of Witwatersrand. She is one of SA’s brightest young researchers who is passionate about science, agriculture and innovation. One of her aims is to further annotate and analyse whole genomes of the nematodes and its endosymbiotic bacteria she isolated in her study. She is currently a postdoctoral research scientist at Wits University and is supervising five masters students and three honours students with Professor Vincent Gray in the School of Molecular and Cell Biology.

Accelerating high-tech training

- Wits University

Wits students contribute to the upgrade of the high-tech software and hardware at the CERN ATLAS detector.

In 2012, the world was astonished by the announcement of the discovery of the Higgs boson at the Centre for Nuclear Reseach (CERN) in Switzerland. That announcement completed physicists understanding of what we know of the part of our world that we can see and feel­­­­­­­­­­­­­­­­, namely normal matter.

The discovery of the Higgs boson, however, inspired the worlds’ physicists into a whole new world of study, searching for the answers to the mysteries of the things in our universe that we cannot see.

“Normal matter, in other words, the things that we can see and feel around us comprises only about 4% of what is actually in the universe. While we know that there is a lot of matter and energy out there we do not really know what it is and how it is related to the known matter.” says Professor Bruce Mellado, the National Contact Physicist of South Africa at the ATLAS experiment at CERN from the School of Physics at the University of the Witwatersrand.

Dingane HlakuluThe Department of Science and Technology funds the South Africa CERN (SA-CERN) consortium. This avenue is essential for South African students and researchers to access this leading global research infrastructure.

Wits is the single largest contributor from South Africa to CERN. This includes theoreticians and experimentalists together with a  group of 35 students from a wide variety of historical and financial backgrounds that are highly involved in the search for new bosons. These students from Wits University spend significant amount of time at CERN, where some of them play an active role in the upcoming upgrading of the ATLAS particle detectors, that is situated in the Large Hadron Collider (LHC). The LHC will be upgraded in 2023-2024 to increase its sensitivity in order to enhance the potential for new discoveries.

“The LHC is the largest particle accelerator in the world, and it is used to accelerate two high energy particle beams in opposite directions in a circular route, and set them on a collision course with each other,” says Ntabiseng Lekalakala, an M.Sc. student from Wits University, who is now based at CERN.

“By colliding the particles against each other at speeds close to the speed of light, we physically break up these particles to see what they are made of.”

These collissions happen at a rate of one every 25 nanoseconds (a nanosecond is one thousand-millionth of a second).

Dingane Hlaluku, a student at the Wits School of Physics, is working on the software upgrade of the detector. He completed his Masters in Physics at Wits in 2017 and has developed a keen interest in software engineering of largely distributed systems. In October 2017, he was invited to deliver a plenary presentation on the status of the detector upgrades to the Tile Calorimeter of the ATLAS experiment – which included some of the world’s top physicists in High Energy Physics.

Joyful Mdhluli“Dingane giving a plenary presentation summarising the upgrade activities of the Tile Calorimeter of the ATLAS detector was a honour to us all,” says Mellado.

One of the biggest challenges at the ATLAS experiment is to sift through the huge amounts of big data that the experiment delivers, and to only capture the relevant data. This is where Dingane’s software update plays a crucial role.

After the upgrade, the readout electronics will need to cope with digital data with full granularity at about 40 MHz, which means the electronics will need to process data at a minimum rate of 9.6 Gigabytes per second to the off-detector readout components. This is equal to downloading three full feature-length Blueray DVDs per second. The off-detector electronics that is used to control, configure and monitor the process will be required to send data at a rate of about 4.8 Gigabytes per second.

“The software is augmented to look for specific signatures from different regions of the detector in three stages/levels and discard uninteresting events in real-time.” says Hlaluku.

In the current configuration of the detector, data is processed, digitized and read out at 100 KHz.


The fourth annual High Energy Particle Physics (HEPP) workshop took place this January 21st to February 2nd at the Wallenberg Research Centre at Stellenbosch. Professor Alan Cornell, from Wits University and a co-chair of the workshop has been instrumental in the growth of the field in South Africa. “It is great to see so many new students choose to do research in our field. The attendance of this year’s HEPP workshop is double that of three years ago,” says Cornell.

Another Wits student who is contributing to the upgrade of the hardware for the ATLAS detector is twenty-four-year-old PhD student Joyful Mdhluli.

Mdhluli has been involved in the ATLAS experiment at CERN for two years. The experience has changed her life.

Ntabiseng Lekalakala and a fellow student working on electronic equipment“I’ve been able to attend lots of conferences, where I’ve met different kinds of people from different parts of the world, and I’ve also learnt a lot about High Energy Physics,” she says.

“I realised that High Energy Physics basically involves a lot of interesting stuff, like astronomy and dark matter.”

Mdhluli’s research is on trying to find materials that can withstand the high levels of radiation for parts of the ATLAS detector.

“If you want to study particles beyond the standard model, you need to get efficient and accurate data, so if the materials in the detectors deteriorate over time, then that means the signals that they get over time are not reliable. So, we are trying to make it as efficient as possible by making sure that the materials they are using will be able to last long periods and will have reliable signals coming through,” she says.

Professor Elias Sideras-Haddad, Mdhluli’s PhD supervisor and a member of the ATLAS experiment, is enthusiastic about training students in nuclear and radiation physics: “The ATLAS experiment operates under high levels of radiation. South Africa has excellent capabilities to undertand how detector components respond to radiation. Our work with the ATLAS experiment opens a new dimension and it demonstrates that South Africa has a lot fo offer,” says Sideras-Haddad.

Wits’ involvement at CERN has already led to actual technological innovation in South Africa, where the Cape Town-based company Trax Interonnect built a new 16-layer electronics board specifically for the ATLAS detector upgrade. This board was until recently the most complex printed circuit board ever produced in South Africa.

“The production of the board for ATLAS was a challenge. Since then, we have improved on our own capabilities and now we are able to produce even more complex boards,” says Daniel Dock, Managing Director of Trax Interconnect.

Speaking at the HEPP workshop in Stellenbosch, Mathis Wiedeking of iThemba Laboratories said that South Africa has a long standing collaboration CERN.

“Student training and the education of our next generation scientists is a top priority and a foundation for research development. South Africa plays a visible role in this field of research and contributes quite significantly,” he said. “The SA-CERN consortium has the capacity to attract young people and get kids interested in science, and it plays a huge role in sparking the interest in sience and technology among young South Africans.”

Mellado agrees. “Our collaboration with CERN provides us with an excellent opportunity to develop human capacity in areas of high-tech that are badly needed in South Africa, contributing to the training of a new generation of leaders. Technology transfer to South African industry is an important by-product of this interaction,” says Mellado.   

Cold-blooded pythons make for caring mums

- Wits University

Female South African pythons are the first ever egg-laying snake shown to care for their babies - at great cost to themselves.

Reptiles are usually thought of as cold-blooded (an outdated term), simple animals that certainly don’t care for their young.

Professor Graham AlexanderBehaviours such as family living and parental care are usually not associated with snakes, and are only associated with mammals and birds. However, this may be more as a result of the lack of research on reptiles, than as a result of their actual behaviour.

A recent study by Professor Graham Alexander from the Alexander Herp Lab at the Wits School of Animal Plant and Environmental Sciences has found that female southern African pythons not only incubate their eggs, but they also stay at the nest, caring for their babies for about two weeks after the eggs have hatched. During this time, the babies spend the nights protected and warmed in their mother’s coils, secure in the nest chamber.

“This is the first-ever report of maternal care of babies in an egg-laying snake,” says Alexander, whose findings are based on seven years of intensive fieldwork at the Dinokeng Game Reserve, just north of Pretoria. During this time, he tracked 37 pythons through the use of radio transmitters. These results, and other surprising discoveries were recently published in the Journal of Zoology (London).

During the study, eight of the radio-tracked pythons laid eggs in aardvark burrows, and Alexander recorded their breeding behaviour using infrared video cameras carefully lowered into the nest chambers.

“I was amazed by the complex reproductive biology of this iconic snake,” said Alexander.

The female python’s protective behaviour towards her offspring comes at great cost to themselves. The females do not eat at all during the breeding cycle – a period of more than six months – and lose about 40% of their body mass over this time. The females also turn black when breeding – a process which Alexander has termed ‘facultative melanism’ – an adaptation that probably increases rates of heating while basking in the sunlight.

“Efficient basking is probably crucial for incubation. Unlike some other python species, southern African pythons are unable to warm their eggs by elevating their metabolism. Instead, our pythons bask near to the burrow entrance until their body temperature is almost 40 °C (within a few degrees of lethal temperatures), and they then coil around the eggs to warm them with their sun-derived body heat.”

The body temperatures of receptive, pregnant and brooding females in the study were more than 5 °C warmer than non-reproductive females. Even the body temperatures of baby-attending mothers were significantly higher than non-breeding females.

“All of this takes its toll on mother pythons: they take a long time to recover after breeding and so can only produce a clutch every second or third year, depending on how many meals they are able to catch in the months after leaving the nest. Some of them never recover.”

A clutch of python babiesAlexander’s team have recorded instances of females breeding of starvation after breeding.

“Perhaps they just became too weakened to catch food,” says Alexander.

Fortunately all the animals tracked during the study survived, but none of them bred in the following year.

Another surprising finding in the study was the fact that the male pythons followed receptive females around for months.

“In one case, one male was recorded following a female for more than 2 km over a three-month period,” says Alexander.

Alexander’s findings suggest that we still have lots to learn about the reproductive biology of snakes.

“Research is showing that snake reproductive biology is far more complex and sophisticated than we previously thought, and there is a range of behaviours that have been recorded in several species that can be classed as maternal care. For example, biologists are discovering that females of many types of rattlesnakes show maternal care of babies. In some species, mothers appear to even cooperate by taking shifts to look after young. But all these species are live bearing – our python is the first egg laying species that has been shown to care for its babies.”

DigiMine, the future of mining research

- Wits University

Celebrating the research of the new Sibanye-Stillwater Digital Mining Laboratory (DigiMine) at Wits University.

To celebrate the launch of the Digital Mining Laboratory (DigiMine) sponsored by Sibanye-Stillwater at the University of the Witwatersrand later this month, the Wits Mining Institute (WMI) will host a seminar on 26 and 27 March 2018 showcasing its high-tech DigiMine and research being done. 

According to WMI director Professor Fred Cawood, the seminar is part of a week-long celebration by the partners in the DigiMine project, which will be formally unveiled on 28 March by Neal Froneman, CEO of Sibanye-Stillwater. 

“The seminar is for anyone interested in digital mining in the underground environment,” said Professor Cawood. “We will be showcasing our laboratory, which comprises a 24/7, digitally monitored, realistic underground mining environment, as well as our research agenda to develop digital technologies for mining applications; delegates will also witness some of our research outcomes that have been developed in recent years by the WMI and its partners.” 

Keynotes at the event will come from two of DigiMine’s key partners: the National University of Sciences and Technology (NUST) in Pakistan, and Sibanye-Stillwater who will give their view of mine digitisation in the 21st century. Presentations will also be made by selected postgraduate research students and partner organisations. Read more

About the Wits Mining Institute (WMI)

The WMI conducts and facilitates multidisciplinary research, encouraging partnerships to ensure a sustainable business model. Its flagship programme is the digital mining laboratory (DigiMine), where its focus is to conduct tests, research and development for transferring surface digital technologies into the underground mining environment. It also identifies and develops skills required to operate 21st century, technologically-intensive mines, which feed into a programme for developing modern skill-sets at artisan, technician and professional levels for the mining sector. Visit

About Sibanye-Stillwater

Sibanye-Stillwater is an independent, global precious metal mining group, producing a unique mix of metals that includes gold and the platinum group metals (PGMs). Domiciled in South Africa, Sibanye-Stillwater owns and operates a portfolio of high-quality operations and projects, which are grouped by region: the Southern Africa region and the United States region. Globally, Sibanye-Stillwater is the third largest producer of palladium and platinum and features among the world’s top ten gold producing companies. Visit

NMW Bill heads to Parliament amid concerns

- National Minimum Wage Research Initiative

The National Minimum Wage Research Initiative at Wits raises concerns over serious shortcomings of the Bills.

The National Minimum Wage Bill 2017 (NMW Bill) – together with the Basic Conditions of Employment Amendment Bill 2017 (BCEA Bill) and Labour Relations Amendment Bill 2017 (LRA Bill) – will be before the Labour Portfolio Committee in Parliament this week. 

This is a momentous achievement. The Freedom Charter famously said: “There shall be a forty-hour working-week, a national minimum wage, paid annual leave, and sick leave for all workers, and maternity leave on full pay for all working mothers”. 

The former Deputy President, Minister of Labour, Department of Labour (DoL) officials, and all those involved in the NEDLAC Wage Inequality Technical Task Team (WITTT) should be congratulated for their roles. 

The National Minimum Wage Research Initiative (NMW-RI) at Wits University has consistently supported the implementation of a carefully-crafted national minimum wage (NMW). The NMW-RI has produced abundant local and international evidence highlighting how this policy intervention can contribute towards reducing poverty and inequality while positively benefiting the economy as a whole. 

With regret however, given serious shortcomings, the NMW-RI cannot support the passing of the Bills in their current form. NMW-RI Coordinator, Gilad Isaacs explains: 

“The National Minimum Wage Bill and associated amendments to the BCEA and LRA contain serious weaknesses that undermine their ability to provide a universal wage floor, reduce poverty and inequality, and protect the most vulnerable workers. The national minimum wage has the potential to play a role in a new wage policy for South Africa – one that moves us away from the apartheid wage structure and contributes towards a new social compact and the structural transformation of the economy. This objective is compromised by the overall package presented in the Bills. Passing the Bills in their current form would be a serious mistake.” 

The NMW-RI is also concerned about the limited timeframes Parliament has to process these Bills. Submissions will be made on the 20th and 22nd of March 2018 and Parliament is due to go into recess on the 29th of March. It is critical that the Labour Portfolio Committee has adequate time to apply its mind to the serious issues raised in the submissions before it. It is worth noting that the Bills presented to the Committee are the same as those published in November 2017 by the DoL despite the DoL receiving detailed submissions in December 2017 and January 2018 regarding the problems contained therein. 

The NMW-RI has made a detailed submission to the Parliamentary process (after an earlier submission to the DoL in December 2018). 

In the submission we note a number of significant positive features of the Bills; amongst others, these include:

  • Recognising the role the NMW can play in reducing poverty and inequality and spurring domestic demand and productivity increases in the economy;
  • Setting the NMW at an acceptable starting point (R20 per hour) that can be increased over time (provided it is accompanied by an appropriate NMW ‘package’ – see below);
  • Supporting universality with certain appropriate tiers and exemption procedures;
  • Excluding non-basic wage payments from the calculation of the NMW;
  • Establishing a dedicated body comprised of the social partners to oversee the implementation, monitoring and revision of the NMW;
  • Amendments to the BCEA that recognise the need for better enforcement. 

We do however point to a number of major shortcomings. 

In the current NMW Bill “worker” excludes “independent contractors”, those that perform task-based work, piecework, home-based work, sub-contracting and contract work. This is because “worker” is defined with reference to the definition of “employee” in the BCEA. These independent contractors – which can range from Uber drivers to shoe makers – are therefore not guaranteed the NMW. This decision, we show, bucks local and international best practice. Our recommendation: a broader definition of worker to include independent contractors must be adopted, the DoL noted in a statement that the narrower definition was made in error. 

The proposed amendments to the BCEA (repealing chapters 8 and 9) irrationally remove a tool available to government to reduce poverty and wage inequality – the ability to amend and create new sectoral determinations (SDs). SDs exist to cover sectors characterised by low levels of collective bargaining and high levels of vulnerable workers, and to implement sector-specific regulation. They set multiple minimum wage levels, many above the new NMW. There is no reason to believe the new NMW removes the conditions that make SDs necessary. We recommended the NMW Commission be given the powers and responsibilities of the current Employment Conditions Commission (ECC) in this regard. 

The NMW Bill does not guarantee that the NMW increases every year – what it does is ensure an annual review. Without guaranteeing a minimum annual increase the real value of the NMW could easily be eroded, thereby undermining its ability to contribute towards reducing poverty and inequality. Further, the role of the ‘medium-term’ target is vaguely specified. We recommend that the Bill ensure, at minimum, an annual increase in-line with inflation as faced by the poor, as well as specify that the medium-term target provides a goal – set in relation to internationally accepted benchmarks – towards which the NMW must be progressively increased over a set period of time. 

The NMW-RI has consistently argued for special protection of those in casual and part-time employment and for ensuring that wage increases due to the NMW do not spur further casualisation and that part-time workers can meet their basic monthly needs. While acknowledging the need for such protection the Bill does not go far enough. The current approach guarantees a worker must be paid for four hours irrespective of the number of hours worked, a minimum number of hours is a positive stipulation. A complimentary approach, as found within some SDs, is to institute a premium on part-time work. In retail, for example, those working less than 27 hours receive an hourly wage about 25-30% higher than those working more than 27 hours. This disincentivises casualisation. Another approach would be to put in place a minimum weekly or monthly national minimum wage in addition the hourly wage, or to increase the minimum number of hours above four. The NMW-RI is not prescriptive as to which combination of these measures should be followed but a more substantive package is needed. 

EPWP workers are effectively excluded from the NMW and an attached schedule sets their wages at R11 per hour. While in principle there is no problem with temporarily setting EPWP wages at a lower “tier”, or percentage of the NMW – as we recommended and is the case for domestic and farm workers – the EPWP rate is not tied to the NMW and could languish at R11 per hour indefinitely. Further, there is no procedure stipulated whereby the level will be gradually raised to reach the general NMW over time. In addition, R11 does not represent a meaningful increase over current levels nor does it come anywhere close to meeting these workers’ basic needs. Excluding EPWP workers also opens the door to abuse of the scheme to circumvent the NMW. We recommend EPWP workers should be included as a “tier” tied to the NMW with the objective of ensuring that they earn the NMW within a set period of time. 

Related, we are concerned that no provisions have been put in place to increase grants to NGOs and small private sector operators, such as in the early childhood development (ECD) sector, which provide vital public services, so that they can afford to pay their staff the new NMW. We recommend government urgently review all such programmes in light of increased wage demands. 

Issues regarding coverage and enforcement are also troubling. The Bills and related documents note the need to train the inspectorate regarding the NMW but seem to imply that it is otherwise well functioning. This is far from the case with serious weaknesses in: a lack of human and physical resources, the allocation of inspectors and their training, no national case management system, and so on. The transfer of responsibility for processing violations of the NMW to the CCMA is similarly full of holes with no sense of how problems within the CCMA will be addressed and new responsibilities will be resourced and managed. 

Of concern also is the system through which businesses can apply for exemptions, and the role of business associations therein, and the potential abuse of this. We recommend the DoL publishes detailed plans with regards to enforcement and exemptions and that these are made available for public comment. 

The Bills also ignore the substantial international evidence regarding the use of business incentives to encourage voluntary compliance and the need for stiff penalties. We recommend the NMW Commission be empowered to review and, together with the appropriate government departments, institute such. 

Finally, we raise a number of concerns regarding the capacity and independence of the NMW Commission secretariat and the powers of the Minister to reject the NMW Commission’s Report. 

As noted above, the NMW must be viewed as a package. Where R20 per hour is combined with universal coverage, guaranteed annual increases, a medium-term plan to increase the amount in real terms, added protection for part-time and casualised workers, stringent enforcement, and strong oversight mechanisms, it can serve as a viable starting point for this policy’s contribution towards changing the wage structure – which must of course be complemented by other policies, including a living wage campaign. However, the Bills before the Portfolio Committee fall short and fail to secure the potential gains from this landmark achievement. 

The NMW-RI hopes that careful consideration by the Portfolio Committee will address these concerns.

For more information, contact:

Dr Gilad Isaacs

Coordinator, National Minimum Wage Research Initiative

Director, CSID research programme

University of the Witwatersrand 

Recreating our ancestral past

- Gillian Anstey

Wits – in the champion’s league of archaeology – hosted the first African Conference on Experimental Archaeology.

Bill Schindler gave a demonstration of experimental archaeology when he screened an episode of National Geographic’s The Great Human Race at the Wits Club as part of the first African Conference on Experimental Archaeology (ACE).

About 60 delegates from around the world watched as Schindler, dressed in skins, darted a boar in the Caucasus Mountains with an atlatl and ate its fat to keep warm – what he described as ‘’an attempt to recreate our ancestral past’’, namely the Ice Age 40 000 years ago.

Schindler co-starred in the TV series with survival expert Cat Bigney but he is the public face of experimental archaeology in more ways than one. Associate Professor of Anthropology and Archaeology at Washington College in Maryland in the US, he is  also chairman of EXARC, an organisation representing about  300 members from 40 countries who are involved in archaeological open-air museums, experimental archaeology, ancient technology or interpretation (such as museum education).

EXARC organised ACE together with Dr Silje Evjenth Bentsen, a Claude Leon Foundation Fellow at Wits.

Schindler says the response from other academics to the TV series has been very positive “because it reached people”. Although one ACE delegate questioned the choice to feature Bigney in a dress, albeit it of skin; another delegate, Sarah Paris, a PhD student from Cambridge University, said she welcomed such popularising of experimental archaeology.

In his keynote address, Professor Innocent Pikirayi of the Department of Anthropology and Archaeology at the University of Pretoria, defined experimental archaeology as “attempts to generate and test hypotheses, usually by replicating or approximating the feasibility of ancient cultures performing various tasks’’.

His own on-going experiments are about documenting water resources at the architectural site of Great Zimbabwe, to work out how it might have shaped the function of the medieval city.  The research involves women carrying water uphill in traditional clay pots but has been affected by unexpected heavy rains which has hindered access.

Pikirayi said that experimenting with prehistoric buildings (architecture) is common at sites such as Stonehenge in the UK but almost unheard of in Africa.

Dr Molapo Qhobela, CEO of the National Research Foundation, spoke of the importance of experimental archaeology in SA today. “Can there be any other place, or any other time in our human history where testing the validity of assumptions about ancient humanity can be more important?

‘’It is widely accepted that there can be no single past that is knowable and acceptable to all. Taking snapshots of the past through different lenses can give many different interpretations. When these snapshots are taken out of their original contexts and put into glass museum cases by experts with a particular world view, for instance, audiences are intentionally or unintentionally lead down a particular path of interpretation.’’

The other keynote speaker, Lyn Wadley, an A-rated scientist and Honorary Professor of Archaeology at Wits, spoke of the pigeon feast she experienced with two of her post-doctoral fellows, Dr Aurore Val and Dr Paloma de la Peňa.

They had found a disproportionate number of pigeons and dove bones, particularly in the early layers of the archaeological site of Sibudu Cave, 40km north of Durban.  Val had conducted an experiment to determine: were the bones present because the birds had roosted and died there, or did they exist for anthropogenic reasons, that is, had people eaten them?

She accessed 16 pigeons which they gutted. Keeping the feathers on some of the birds, they wrapped those in strelitzia leaves and roasted among coals. The others were grilled. All were eaten with their fingers to emulate how they might have been eaten.

“We didn’t really enjoy the ones with the feathers very much,’’ said Wadley to much amusement from the delegates, “and so we compromised a bit”, she said, pointing to a picture of Val adding olive oil and rosemary to those being grilled.

“Yes, we ate all 16 of them,’’ she said. It took two days. They tasted “really disgusting’’ exclaimed Val, but they proved from perforations left on the soft bones from tearing them apart, and from tooth marks, that people living at Sibudu during the Middle Stone Age had eaten the birds. The experiment was published in the Journal of Human Evolution in 2016, with Val as the first author.

Co-organiser Bentsen said she had initiated ACE because people at international conferences often spoke of the need for it. Senior lecturer Dr Christine Sievers, pointed out that archaeology at Wits ranked 38th in the world in the 2018 QS university subject rankings. ‘’It’s a hub,’’ said Bentsen. “You really feel like you are working in the champion’s league when you work at Wits.’’

ACE was sponsored by the French Institute of SA (IFAS-Recherche); the Palaeontological Scientific Trust (PAST); BRUKER; the DST-NRF Centre of Excellence in Palaeosciences at Wits;  with support from the NRF-SARChi Chair of Modern Origins, Professor Christopher Henshilwood.