Quest 1(1) by Academy of Science of South Africa

Science for South Africa

ISSN 1729-830X

Volume 1 • Number 1 • 2004 R20 incl. VAt

Academy of Science of South Africa

Cover stories

Crackdown on invasive aliens Brian van Wilgen The Working for Water success story and a Fact File 16 Genetics and race Trefor Jenkins How clear, really, is the biological definition of race?

HIV/AIDS ■ Getting the numbers right ■ South Africa’s Plan for treating HIV and AIDS Anthony MBewu

Quest for our earliest ancestors – the fossil story Ron Clarke

Contents VOLUME 1 • NUMBER 1 • 2004

News of the 4-million-year-old Sterkfontein homind skeleton

Features

Regulars 28

Birding around the world

Careers

■ Save that wanderer John Cooper Helping seabirds under threat

Work in the world of water

■ E-mail from Thailand Alan and Meg Kemp Exploring the Malesian rainforests E-learning for a ‘new’ economy

An apple a day (p.15) • Ancient fish ancestor of land animals; Jewellery – the oldest ever found; Tracking fishes in the Eastern Cape (p.36) • High-level support for nuclear fusion; Inkaba ye Africa for the country’s earth sciences (p.37) • Fifteen-year-old NASA winner; SA WISE; Crime and drugs (p.42) • Cool technology; Microscopic computers to fight cancer in the cell? Vaccines against global warming? (p.43) • USA losing dominance in science? (p.46)

Science news

Martin Hall Virtual universities for Africa? 33

The S&T tourist Elephant rock – George Roberts

Flashback to 1904

Visit dolomite next time you’re in South Africa’s northern provinces

Centenary year for the South African Journal of Science

Puzzles Calculate from Sedna’s scientific name 41

• Crossword

Viewpoint The plague of environmental absolutism – George Ellis

The sky’s the limit ■ Discovering the planet(oid?) Sedna ■ Star gazers at SAAO Patricia Whitelock Training African astronomers

Getting to know science UWC and Sci-Bono help make SA more competitive

Books

The Abundant Herds: A celebration of the Nguni cattle of the Zulu people, by Marguerite Poland, David Hammond-Tooke, and Leigh Voigt • and other titles 46

Diary of events

ASSAf news

Subscription form • Back page science

Still counting 19

■ Surveying South Africa’s R&D How have we progressed?

■ Measuring up Crumbs & nibbles, sheds & barns

Quest 1(1) 2 0 0 4 1

Preparing samples for a PCR (polymerase chain reaction) machine, which copies the region of DNA to be amplified for sequencing. (In the Department of Human Genetics, Molecular Genetics Laboratory, School of Pathology, University of the Witwatersrand and the National Health Laboratory Service.) Photograph: Erik Föster, www.peach.co.za

SCIENCE FOR SOUTH AFRICA

ISSN 1729-830X

Editor Elisabeth Lickindorf Assistant Editor Eldene Eyssell Editorial Board Wieland Gevers (University of Cape Town) (Chair) Graham Baker (South African Journal of Science) Anusuya Chinsamy-Turan (University of Cape Town) George Ellis (University of Cape Town) Jonathan Jansen (University of Pretoria) Colin Johnson (Rhodes University) Correspondence and The Editor enquiries PO Box 1011, Melville 2109 South Africa Tel./fax: (011) 673 3683 e-mail: editor.quest@iafrica.com (For more information visit www.assaf.ac.za) Business Manager Neville Pritchard Advertising and Neville Pritchard Subscription enquiries PO Box 5700 Weltevreden Park 1715 South Africa Tel.: (011) 678 7093 Fax: (011) 673 3683 Cell: 083 408 3286 e-mail: pritchardn@mweb.co.za

e chose the title of our new popular science magazine because the word ‘quest’ means many things – adventure, crusade, exploration, hunt, inquiry, mission, pilgrimage, pursuit, venture, undertaking. All these describe what scientists and researchers do. Now, through QUEST: Science for South Africa, the rest of us can travel parallel paths as we read about their achievements and what these mean to us. QUEST magazine explores science and technology. At the first milestone – in this launch issue – we’re finding out about new South African discoveries. Each new issue will be a refuelling stop that brings with it the urge to explore further. The work that South African scientists do is reported in the academic research journals, much of it abroad. Their articles add to the world’s store of knowledge and provide building blocks for colleagues in scientific fields to conduct further research. But the results are written up in technical language that is often hard to understand. QUEST gives those same scientists another kind of voice. Here they tell us themselves what they’re investigating and what they’re finding out. In a way that we can follow, even if we don’t have their expertise. The authors writing in this issue work in fields as far apart as astronomy and genetics, palaeoanthropology and ornithology. Because they write as specialists, we’re getting reliable and informed judgements and opinions. If we disagree or want to follow up, we can check their recommendations for reading in greater depth in the professional literature or on the Internet. A great body of knowledge is being generated in our very own country. It’s time we found out more about it. We are celebrating our first decade of democracy with a new burst of scientific energy. We have a new ministry of Science and Technology and a new minister of science and technology, Mosibudi Mangena. We welcome him warmly, and we appreciate his department’s determination to keep expanding our country’s activity in these fields. We’ll spread the news by asking our scientists to write it up for us, so that everyone can join in the applause. South African science is an optimistic activity. In quest of solutions, there’s no known problem it doesn’t take on. In the pages that follow we read of science that keeps trying – to find out how best to deal with HIV and AIDS, to secure our water supplies, to get to know our earliest ancestors, to build a world-class knowledge economy. QUEST is here to send us on the same journeys.

Copyright © 2004 Academy of Science of South Africa Published quarterly by the Academy of Science of South Africa (ASSAf) PO Box 72135, Lynnwood Ridge 0040, South Africa (011) 673 3683 Permissions Fax: e-mail: editor.quest@iafrica.com (011) 678 7093 Back issues Tel.: Fax: (011) 673 3683 e-mail: pritchardn@mweb.co.za Subscription rates (4 issues and postage)

Elisabeth Lickindorf Editor – QUEST: Science for South Africa Join QUEST’s knowledge sharing activities ■

Write letters for our forthcoming, regular Readers’ Letters column – e-mail or fax your letter (keep it as short as possible) to the Editor. (Write QUEST LETTER in the subject line.)

■

Ask S&T questions for specialist members of the Academy of Science of South Africa to answer in our regular S&T Questions and Answers column – e-mail or fax your questions to the Editor. (Write S&T QUESTION in the subject line.)

■

Inform our readers in our regular Diary of Events column of S&T events that you may be organizing. (Write QUEST DIARY clearly on your e-mail or fax to the Editor, and provide full details.)

■

Contribute if you are a specialist with research to report. Ask the Editor for a copy of QUEST’s Call for Contributions (or find it at www.assaf.ac.za), and make arrangements to tell us your story.

(For subscription form, other countries, see page 48.)

South Africa (incl. VAT) • Individuals – R80.00 • Students/Schoolgoers – R40.00

Production Pritchard Productions cc Design and layout Creating Ripples Printing Paradigm All material is strictly copyright and all rights are reserved. Reproduction without permission is forbidden. Every care is taken in compiling the contents of this publication, but we assume no responsibility in effects arising therefrom. The views expressed in this magazine are not necessarily those of the publisher.

2 Quest 1(1) 2 0 0 4

To contact the Editor, send an e-mail to: editor.quest@iafrica.com or fax your communication to (011) 673 3683. Please give your full name and contact details.

Welcome to QUEST: Science for South Africa is the new science magazine that the Academy of Science of South Africa is publishing to help inform South Africans (and others) of this country’s contributions to scientific knowledge, and to promote and brand our achievements. We also intend it to provide a forum for active exchange between scientists and the public, and to encourage an interest in science among young people. By ‘science’, ASSAf means something more than the narrowly designated group of ‘natural sciences’, which the Oxford English Dictionary defines as “the sciences used in the study of the physical world, e.g. physics, chemistry, geology, biology, botany,” and which illustrate the term ‘science’ as meaning “a branch of knowledge conducted on objective principles involving the systematized observation of and experiment with phenomena, especially concerned with the material and functions of the physical universe.” The Academy draws instead on the The Academy of Science of South Africa broader definition of science as has a particular emphasis on excellence “systematic and formulated in the application of scientific thinking to knowledge, especially of a the problems and challenges facing South specified type or on a specified subject (e.g. political science); African society. It draws its membership the pursuit or principles of this”. from all population groups and from all As a result, ASSAf views the scientific disciplines. humanities and social sciences as being just as ‘scientific’ as physics or physiology, and has accordingly included in its scope all the sciences. We believe, in this multidisciplinary age, that the allegedly fixed boundaries between so-called ‘disciplines’ are artificial and temporary, and that scientific enquiry as a whole, based on seeking evidence to support and elaborate ideas and hypotheses, is the thing we call ‘Science’ (in the singular), as captured in the name of the Academy. You could say: many sciences make Science. For this reason, too, we include the areas covered by the popular phrase ‘science and technology’ in the broader, all-encompassing domain of ‘Science’. ‘Science’ is, essentially, a quest to explain, understand and use things, processes, and experiences that we encounter on this earth in our individual and collective lives. It is a ceaseless quest because the number of things we can look into is infinite. Our huge scientific resource is that we are uniquely able to build endlessly on each other’s insights, theories and skills, standing on the shoulders of past giants to peer into and keep understanding better the less-understood world beyond. This is the quest that our new magazine will celebrate for our country’s readers, which is why our subtitle is “Science for South Africa”. Enjoy!

The Academy of Science of South Africa (ASSAf) The Academy was inaugurated in May 1996, in the presence of thenPresident Nelson Mandela, the patron of the launch. Activist in its mission of using science for the benefit of society, ASSAf has a mandate encompassing all fields of scientific enquiry, and includes in its ranks the full diversity of South Africa’s distinguished scientists. In 2001, South Africa’s parliament passed the Academy of Science of South Africa Act, Act 67, which came into operation on 15 May 2002. This Act has make ASSAf the country’s official academy of science, recognized by government, and representing South Africa in the international community of science academies.

Objectives Scientific thinking for the good of society In terms of the Act, the objectives of the Academy are: ■

to promote common ground in scientific thinking across all disciplines

■

to encourage and promote innovative and independent scientific thinking

■

to promote the optimum development of the intellectual capacity of all people

■

to provide effective advice and facilitate appropriate action in relation to the collective needs, opportunities, and challenges of all South Africans

■

to link South Africa with scientific communities at the highest level, in particular within the Southern African Development Community, the rest of Africa, and internationally.

For more information visit www.assaf.ac.za

Wieland Gevers President of the Academy of Science of South Africa (ASSAf)

Quest 1(1) 2 0 0 4 3

CRACKDOWN ON ‘Working for Water’ is a role model for the developing world. Its attacks on alien plants have been saving our unique biodiversity, securing our water supplies, and creating jobs and training for the poor. The CSIR’s Brian van Wilgen explains the part that science played in this success.

How aliens arrive Unprecedented growth in human populations, together with accelerated global trade and travel, means that large numbers of species of plants, animals, and microorganisms (including disease organisms, agricultural weeds, and insect pests) are brought into parts of the world where they were never found before. Some species are deliberately introduced for use in agriculture, as crop species, for instance; in forestry and agro-forestry for timber and firewood; in landscaping and gardens as hedges or ornamental plants; for stabilizing sand dunes, and in the pet trade. Many arrive accidentally, in containers of goods coming in by ship, on aircraft, in postal items, and in ships’ ballast waters.

Mass destruction Some alien species, when transported to a new continent, exhibit ‘ecological release’, a phenomenon that allows them to multiply rapidly (because they no longer have natural enemies) and to out-compete native species. They can survive, reproduce, and take over a territory – sometimes at alarming rates.

Above: Working for Water contractors clear steep slopes of invasive alien pines in mountain catchment areas of the Western Cape. Formerly out of work, they have been specially trained in chainsaw use and in absailing. Photograph: Fran Hunziker

▲ ▲

n October 1995, at just the time when the country needed to take conservation seriously and thousands of job-seekers were needing employment, the then Minister of Water Affairs and Forestry, Professor Kader Asmal, launched the Working for Water Programme. Invasive alien plants and animals throughout the world damage natural ecosystems and their ability to provide for human necessities. The destruction needs to be brought under control. This programme has succeeded because it combines the ‘work’ of clearing huge areas of aliens with the goal of delivering more ‘water’. It inspired buy-in from politicians, economists, and environmentalists alike in the way it created jobs for previously disadvantaged South Africans to protect natural resources under threat. South Africa’s scientific community helped in diagnosing problems and finding solutions. Working for Water’s extraordinary opportunities for experimentation and research took scientists into a new dimension, from academic debate to large-scale implementation. It also cemented the country’s position as a world leader in cracking down on invasive alien plants.

Quest 1(1) 2 0 0 4 5

Major invasive plant species in South Africa Species

Origin

Reason for introduction

Impacts

Approximate area invaded

Syringa (Melia azedarach)

Asia

Ornament; shade

Replaces natural vegetation; uses excessive water

Occurs in 3 million ha along river banks, disturbed areas, roadsides, urban open spaces

Spanish reed (Arundo donax)

Mediterranean

Ornament; screening

Invades river courses; reduces access; increases fire hazard

Occurs over 200 000 ha, mainly along rivers

Pines (Pinus species)

North America; Europe

Timber, poles, firewood; ornament; shade

Replaces natural vegetation; uses excessive water; increases fire hazard

Occurs in 3 million ha; widespread in mountain catchments, forest fringes, grasslands, and fynbos

Black wattle (Acacia mearnsii)

Australia

Shelter; tanbark; shade; firewood

Replaces natural vegetation; uses excessive water; increases fire hazard

Occurs in 2.5 million ha; widespread except in arid areas

Lantana (Lantana camara)

Central and South America

Ornament; hedging

Replaces natural vegetation; reduces grazing and access

Occurs in 2.2 million ha of forest and plantation and margins, water courses, savannas

Gum trees (Eucalyptus species)

Australia

Timber; firewood

Replaces natural vegetation, especially along river courses; uses excessive water

Widely scattered in 2.4 million ha in all areas

Rooikrans (Acacia cyclops)

Australia

Dune reclamation; shade; firewood

Replaces natural vegetation; excessive water user; increases fire hazard

Occurs in 1.9 million ha, mainly in the southern and western coastal belt

Port Jackson willow (Acacia saligna)

Australia

Dune reclamation; shade; fodder; tanbark

Replaces natural vegetation; uses excessive water

Occurs in 1.9 million ha, mainly in the coastal lowlands of the Western Cape

Facts about Working for Water ■

Launched in October 1995

■

Won the Green Trust Award for the best conservation project of 1996

■

In the first five years it

■ ■

Alien plant encroachments are very expensive. They compromise the stability of our ecosystems, erode our natural capital, and threaten our economic productivity.The problem is now as important as environmental threats posed by direct habitat destruction and global climate change.

• grew from 10 projects (1995) to 313 (2000) • cleared alien plants from a total of 716 000 ha countrywide • increased employment from some 6 700 people (1995) to 22 000 (2000) Runs in all 9 of South Africa’s provinces Budget in 2002/03: R421 million

■

Total budget since inception: R1.95 billion

■

Number of people employed in 2002/03: 21 754 (55% of them women)

■

Area cleared of aliens in 2002/03 (all densities): 266 497 ha

■

Area followed up in 2002/03 (all densities): 523 618 ha

(see Working for Water Annual Report: 2002/03) Photograph: Fran Hunziker

6 Quest 1(1) 2 0 0 4

▲

Many aliens introduced into South Africa have become naturalized, surviving in the landscape without needing to be tended, and some of these species have become invasive. A recent study revealed 117 widespread and abundant plant invaders and 84 ‘emerging’ plant invaders in the country. These plants affect almost 10 million hectares (8.28%) of the country, and are spreading rapidly. Our unique fynbos vegetation is all but overrun in many places with pines, hakeas, and wattles; eucalypts, poplars, willows, and wattles infest the banks of many of our rivers; and mesquite trees are invading the Karoo and the Kalahari. Lantana and triffid weed cover numerous bushveld areas. Dams in the country are covered in floating mats of water hyacinth, water lettuce, and other aquatic species. New invasives are continually introduced and taking hold. In Gauteng, for instance, we notice ever-increasing fields of purple-flowering pom-pom weeds. Alien encroachments are very expensive. They compromise the stability of our ecosystems, erode our natural capital, and threaten our economic productivity. The problem is now seen as being as important as the environmental threats posed by direct habitat destruction and global climate change: it is costing billions each year.

The fight for water

Costs of invasion in South Africa (when US$1=R10) Studies reveal that ■

invasions have reduced the value of fynbos ecosystems by over R117.5 billion

■

the total cost of invasion on the Agulhas Plain alone would be about R32 billion

■

the net present cost of invasion by black wattles amounts to R14 billion

■

invasions by red water fern have cost R580 million

■

the cost to clear the alien plant invasions in South Africa is around R12 billion.

Opposite page: Applying herbicides to the stumps of felled invasive alien wattles to prevent cut stumps from sprouting again. Below left: 1985: Invasive Australian wattles along the Wemmershoek River. They use more water than the natural streambank vegetation they replace and they destabilize river banks.

▲ ▲

As long ago as the 1930s, concerns were raised that planting forests of alien trees in South Africa would reduce the country’s water resources. Experiments in water catchment areas and economic assessments began in 1936 and continued over the years. An understanding of the magnitude of the problem began in the 1970s when, basing their predictions on research conducted by the South African Forestry Research Institute on the effects of

forests on streamflow, scientists began demonstrating the effects of alien invasions not only on indigenous vegetation, but also on vital water resources. Alien plant clearing programmes dating from the early 1970s had fallen behind in the late 1980s in the face of competing demands for funding to address poverty, education, health care, and other needs. When Asmal became minister in 1994, it was being predicted that uncontrolled invasion of the catchment areas around Cape Town, for example, could reduce water resources by 30–60% over the next half century for the rapidly-growing city, its industries, and its agriculture. Such losses would mean, amongst other things, that more dams would need to be built much earlier to meet water demands – a costly solution for an economically vulnerable developing country. The costs of clearing programmes (to reduce the excessive amounts of water used by invading alien plants) compared with the costs of developing new water supply schemes revealed that more water could be delivered at lower cost when clearing operations were in place. The sooner such operations were under way the better, as rapid alien plant spread meant exponential increases in the clearing costs the longer the problem was left unattended. Asmal received costing analyses in July 1995. Within three months he had initiated Working for Water, which brought together ecologists, forest hydrologists, and engineers in the task of turning these predictions into water resources planning. For the first time, ecologists were working with water resource engineers to address the holistic planning of dams in the context of catchment management. And major funding was secured and maintained (budget in 2002 of over R400 million) when it was recognized that employing people to deal with

Below right: 2003: The same site after clearing. Streamflow is back to the levels typical of an uninvaded river, but scientists need to develop guidelines for promoting the reestablishment of natural vegetation.

Photographs: D.M. Richardson

Quest 1(1) 2 0 0 4 7

▲

the problem could both protect this vital ecosystem service and provide jobs and upliftment in poor rural communities. Not all alien plant infestations use more water than the natural vegetation they replace. We do know, however, that trees tend to use more water than grasses or shrubs and that the greatest impacts occur when seasonally dormant vegetation is replaced by evergreen plants. Where grasslands or shrub lands are invaded by alien trees, the overall water use by the total vegetation increases, which leaves less water for the streams. Many questions remain, and research still needs to be done. Most of our understanding is based on measurements of water use by a few species of invasive trees – we need to broaden our investigations to other species of trees, and to improve our ability to model impacts across larger tracts of land. Despite many unanswered

Winning with biological control ■

In South Africa, 44 invasive alien plant species have been successfully targeted for biological control.

■

Altogether, 86 species of biological control agents have been released in South Africa since 1913, of which 23 failed to establish.

■

The 63 successfully established agents have reduced the invasiveness of the targeted species and made control much easier.

■

In the case of 11 invasive alien plant species, they have brought the species under complete control, making control by other methods unnecessary.

Top left and right: Clearing areas of terrestrial invasive alien plants. Top middle: At the new Vulindlela disabled centre in Mpumalanga, Working for Water provides training opportunities for the disabled. Right: One of the many women employed in the plant clearing programme.

8 Quest 1(1) 2 0 0 4

questions, South Africa leads the field in assessing the hydrological impacts of invading species, especially in the ways we use a range of methods to construct the bigger picture, and our work on costing impacts of alien plant invasions on water resources remains the most cited scientific example in the field.

Weapons of biological control Another way to halt the invasion is through biological control, and here too South Africa is a world leader. Biological control is the practice of importing plant-feeding insects and plant pathogens (the plants’ ‘natural enemies’) from their country of origin and then releasing them into the new environment where the plants have become a problem. In a successful operation, the natural enemies damage or kill the target plants, resulting in declining populations and reduced rates of spread of the problem plants. Before releasing any natural enemies (also called ‘biological control agents’), scientists conduct rigorous scientific safety tests under strict quarantine protocols. The tests – which can take as long as several years for a single agent species – are designed to make sure that the intended agent is sufficiently host specific, that is, that it can feed and live on only one or a very limited number of closely-related species of host plants. With the death of the host plant(s), the agent cannot feed or survive on any other plant species, and the agent population dies out together with its food supply. Host-specific plant-feeding insects and pathogens that are restricted to only one species of plant are overwhelmingly the best control agents to use. The safety of using plant-feeding insects and pathogens to control weeds relies on meticulous scientific research. It needs good judgement and careful assessments of the benefits to weed management and the risks to non-target plants. The safety record is excellent because of the rigorously regulated pre-release tests, and the need for approval at a high administrative level before any agent can be released. For nearly 150 years, biological control has been a key weapon around the world in suppressing alien, invasive problem plants successfully. Without it, weed management would be beyond the capabilities and resources of most countries. It is a particularly attractive option because it is cost effective and safe, compared with the expense and risks of herbicide development and deployment; it can be integrated with other management practices; and, most compelling of all, it is self sustaining. Biological control has to be one of the country’s best investments, if we compare the benefits of controlling alien plants with the costs of biological control research. The annual economic benefits of preventing invasion ranged from R300 per hectare for jointed cactus, to R3 600 per hectare for golden wattle. Historical analyses of the benefit:cost ratios from the time the biocontrol

Photographs: Fran Hunziker

Research build-up From 19–21 August 2003, Working for Water held its inaugural research symposium at Kirstenbosch. Based on the presentations, the South African Journal of Science published a special research issue in early 2004 with 19 papers by 42 authors from 11 institutions in South Africa and abroad. The collection of papers collates information from widely dispersed reports, and presents a holistic picture of the programme’s achievements, the research that backs up the assessments of impacts, and the challenges that lie ahead for the programme.

agent was released to the year 2000 ranged from 8:1 for lantana to an astonishing 709:1 for jointed cactus. In other words, for every R1 invested in biocontrol research for jointed cactus, R709 worth of benefits were generated. The conclusion is that an even greater investment should be made in biological control research. This will help the country get the maximum benefit from the most cost-effective and sustainable control technology available. It will also build South Africa’s excellent track record as world leaders in this internationally transferable field, and grow a new generation of biocontrol researchers for the country.

What now?

▲ ▲

The struggle continues. We need to expand our fundamental understanding of the processes that underlie invasions and their effects, so as to underpin more holistic assessments of the problem. Scientists have to answer many compelling questions. Here are some of them. • What is the sum total of impacts (and benefits where these exist) associated with invasive alien plants, and how do these vary for different species and in different geographic areas? Once we know more, we can adjust our priorities. • How can the benefits arising from costly control programmes be expanded, for example, by using the opportunity to create employment, and to reduce costs by making use of the plant material from clearing operations? • How can we find better ways to identify dangerous species at an early stage, given that new species are entering the country all the time? • What are the best arguments to justify putting measures in place to control or eradicate ‘emerging’ problem species, given that problems

with existing and obvious invasions have priority (and that problem prevention seldom carries political kudos for funders)? • How can we best deal with the significant conflicts of interest arising when invasive alien species also provide certain important benefits? To answer, and to find solutions, we have to have objective and unbiased information based on good science. (Does it make sense, for example, to propagate sterile cultivars, or to reduce invasive potential by introducing seedfeeding insects?) • How best can we combine and integrate skills from different disciplines to address the problems of invasive alien plants holistically and to develop integrated solutions? (The field of resource economics, for example, needs inputs from ecologists, hydrologists, engineers and social scientists for economic simulations to inform decision-makers of the full consequences of invasions and the benefits of control.) The opportunities for creative experimentation and research are endless in the Working for Water programme – in the range of ecosystems where clearing projects are located and in the scale of operations. Here are largely unexploited openings rarely to be found anywhere else in the world. We need to capitalize on them. For further details consult the special issue of the South African Journal of Science, vol. 100, no.1–2 (2004), as well as T. Olckers and M.P. Hill (eds.), Biological control of weeds in South Africa (1990–1998), African Entomology Memoir No. 1 (1999), and L. Henderson, Alien weeds and invasive plants: Plant Protection Research Institute Handbook Number 12 (Pretoria: Agricultural Research Council, 1999).

Top left: Invading Australian wattles replace seasonally dormant grasslands with evergreen cover that depletes soil water all year round. This leaves less water to recharge groundwater and maintain streamflow and reduces biodiversity and grazing potential. Top right: Clearing Port Jackson willow in the West Coast National Park. South African National Parks is an important implementing agent for clearing programmes. Through Working for Water, poverty-relief funding provides work for local communities and protection for the parks’ natural biological assets. Above: A member of the elite ‘high altitude’ team. Previously unemployed people have been trained in chainsaw use and mountain climbing, survival, and rescue. They clear invasive trees in high inaccessible areas to prevent seeds from re-infesting cleared lowland areas below.

Dr Brian van Wilgen is at the CSIR Division of Water, Environment and Forestry Technology, PO Box 320, Stellenbosch 7599.

Quest 1(1) 2 0 0 4 9

Fact file Q

Working for water ▲

What’s wrong with alien invaders?

A few ‘007’ control agents

They may

■

use too much water and block out light for other plants

■

pollute drinking water (e.g. water hyacinths)

■

reduce streamflow and yields from dams and the ability of catchments to store water, and they clog irrigation canals and pumps

■

reduce grazing lands and land productivity

■

increase the use of potentially harmful chemical herbicides and pesticides

■

accumulate or redistribute salt in soil

■

change living space or habitat, sediment, light, and water, reducing abundance and diversity of native plants and birds

■

prevent replenishment of sand on beaches, leading to beach erosion

■

accumulate litter and increase biomass (woody material and foliage), creating fire hazards, soil erosion, and flooding from rapid runoff after rain

■

shade river banks, strangle forest/woodland canopy (e.g. cat’s claw creeper), and act as ‘ladder fuels’ (e.g. triffid weed) carrying fire to tree canopies

■

reduce capacity for boating, canoeing, waterskiing, and fly fishing

■

reduce freshwater input to estuaries and change the frequency of opening and closing of the mouth, making estuaries unsuitable for nursery sites for important marine fish species

■

disturb indigenous insect populations, for example, dragonflies, of which many species are endangered (especially by black and long-leaved wattle alongside rivers and lakes: shade trees prevent growth of grasses and bushes where dragonflies lay eggs, and their habitat is disturbed by cattle seeking the aliens’ shade).

■

Plant-eating cochineal insects (used for making food colouring) were introduced in 1913 and since then have provided sustained, day-by-day, cost-free control of drooping prickly pear (Opuntia monacantha). The cactus moth, Cactoblastis cactorum, was mass-reared near Uitenhage and released against sweet prickly pear (Opuntia ficus-indica) in 1933. A cochineal insect (Dactylopius austrinus) was released in 1935 to control jointed cactus (Opuntia aurantiaca). Mass-reared near Uitenhage, these insects are provided free of charge for manual re-distribution as needed.

■

Two species of gall-forming pteromalid wasps have been used successfully against long-leaved wattle (Acacia longifolia) and golden wattle (A. pyncantha).

■

A fungus has been deployed against the Port Jackson willow.

■

A cone-feeding weevil species with potential to reduce seeding in cluster pine (Pinus pinaster) is being tested in quarantine.

■

The leaf-feeding beetle (Chrysolina quadrigemina) and bud-galling midge (Zeuxidiplosis giardi) have brought St. John’s wort (Hypericum perforatum) under control in the Western Cape.

International trade and travel creates pathways for invaders (e.g. marine organisms in ship ballast water, contaminated soil and seed lots).

■

Growing demand for forestry products increases plantation areas of invasive tree species (e.g. pines, eucalyptus).

■

Internet and global databases spread information about useful plants, prompting horticulturists and others to import species without considering potential invasiveness.

■

Road and rail networks transport seeds, which can also be carried by earth-moving and construction equipment, and in construction materials.

■

Horticultural fashions drive demand for new species of flowers, bushes, shrubs, trees, and ground covers, many of which are weeds.

■

Laws, policies, and regulations to control, import, plant, and manage known and potential invader species are either not in place or are not implemented or upheld.

‘Conflict-of-interest’ alien species Not everyone wants to get rid of: the jacarandas that purple our cities and gardens; pine trees, which underpin large commercial activities, such as plantation forestry; eucalyptus (gum) trees, which provide timber, poles, firewood, nectar and pollen for honey production, and pollinators for the deciduous fruit industry.

Benefits for people Working for Water has: created jobs; funded poverty relief; encouraged small enterprises of contractors to help to clear land, sell firewood, and make products from wood and bark; spread HIV/AIDS education; forged partnerships with organizations able to employ, train, and manage workers in alien plant-clearing; given training; emphasized gender redress; re-integrated former prison inmates; and raised public awareness of destructive aliens.

Biological control How biological control agents attack invaders: depending on the type, they can – chew and devour plant tissue, or mine or bore into the plant; suck the sap; induce plant-galling (growths); produce necroses (dead tissue) and rust spots; eat the seeds; and stunt the growth of young plants, which then take longer to mature and produce fruit.

How humans help the aliens

■

Modern industries can increase atmospheric CO2, encouraging alien grasses that photosynthesise more efficiently.

Some biological control agents: weevils and their close relatives; families of beetles; sucking bugs; butterflies and moths; flies; pathogenic fungi; plant-feeding wasps.

■

Fertilizers and atmospheric pollution deposit more nutrients in natural ecosystems, benefiting alien invaders more than native species.

They act by damaging vegetative tissues (leaves, petioles, stalks, stems); reproductive tissues (buds, flowers, seeds, pods); sap drained from the phloem vessels.

■

Growing human populations demand more food (encouraging more use of fertilizers, imported species, and increased areas under production).

10 Quest 1(1) 2 0 0 4

■

People change environments so that native species decline or become extinct, making room for alien invaders to move in.

Do’s and Don’ts ■

Do plant indigenous plants and buy from certified indigenous plant nurseries.

■

Don’t import potentially invasive plants and don’t plant evergreen trees, or ‘thirsty’ trees and reeds near streams, or grasses such as pampas grass, fountain grass, Spanish reed, and feather-top (all these are prohibited Category 1 weeds in South Africa).

■

Do remove these weeds from your garden: Cape gooseberry, Chinese elm, common privet, cosmos, elephant’s ear, eucalyptus, evening primrose, forget-me-not, Formosa lily, giant reed, guava, lantana, moon cactus, moonflower, morning glories, New Zealand bottlebrush, oleander, pampas grass, potato creeper, purple pom-pom weed, queen of the night, redstar zinnia, Spanish broom, sword fern, syringa, thorn apples, tree daisy, weeping willow, white or grey poplars, white or common mulberry, white ginger lily, wild tobacco, yellowflowered Mexican poppy. ■

For more see South African Journal of Science, vol. 100, no. 1–2 (2004) and consult R.P. Randall’s A Global Compendium of Weeds (Melbourne: R.G. and F.J. Richardson, 2002).

Q Careers in S&T

WORK IN THE

world of water W ater in South Africa is precious. We use water in every walk of life and our economy depends on reliable sources of good quality water. At every stage in the water cycle, trained people at all educational levels look after water, store it, make sure it is clean enough for use, and help people and industries everywhere to have access to it. Some careers are specific to water, such as the work that’s done by a hydrologist or a wastewater plant process controller. Others offer specializations in water, as in the fields of chemistry, ecology, engineering, geology, microbiology, or the making of instruments. Many careers are not specific to water, but the world of water can’t do without them, such as accounting, information technology, public relations, and the social sciences. There are plenty of opportunities* for worthwhile work wherever people need water. An aquatic scientist An aquatic scientist studies inland and marine water environments: physical (including temperature, water current and rates at which water flows, erosion, and sedimentation); biological (plants, animals, and microbes that live in water); chemical (e.g. water quality and sewage disposal); and ecological (e.g. ways in which organisms interact with their environments, effects of pollution, and matters that affect the way food is produced and used). Aquatic scientists are involved in managing water resources, and their time is divided between the laboratory and outdoors. To prepare for their work, they need matric level mathematics, physical science, or biology. They need to enjoy working outdoors, and to be practical and well organized. They can enter this field with a National Diploma in Analytical Chemistry, for instance, or a B.Tech. (Water Care), or a B.Sc. in the natural sciences, or an honours degree in limnology and ecology. They’ll find work in many places, such as in municipalities, science councils, nature conservation organizations, and water utilities.

A civil engineer

A civil engineer in the world of water plans, designs, constructs, and maintains water supply systems, dams, irrigation, water purification plants, stormwater systems, flood control structures, sewerage works, harbours, docks, canals, and bridges. She or he needs to know about construction materials, soils, hydraulics, and fluid mechanics, and also be concerned for protecting and conserving the environment. Civil engineering technicians do much of the practical work, and technologists do the more theoretical work (e.g. planning, design, or research). Careers in civil engineering mean working on site as well as in an office. Useful matric subjects include physical science and mathematics, computer studies, geography, and technical drawing. Civil engineering needs people who are practical, and good at visualising objects three-dimensionally. With a diploma or degree in civil engineering, there’s work in engineering and construction firms, in government departments (such as the Department of Water Affairs and Forestry) and municipalities, and in corporations such as Iscor and Eskom. A plumber

A plumber installs, maintains, and repairs pipes, plumbing systems, and fixtures in houses, factories, plants, and construction sites. This work is essential wherever fresh water needs to be supplied and wastewater removed. Plumbers work indoors and outdoors, in all kinds of weather. They can specialize – in irrigation systems for parks and golf courses, for instance, or sprinklers for fire protection systems. Training is available at technical colleges and in apprenticeships, and there is a compulsory Department of Labour trade test to qualify as an artisan.

For details of more than 50 types of job in the world of water, with summaries of many others, see the Water Research Commission’s publication, Water@Work: A career guide (available from mid-July 2004). To receive a copy, contact Dr Steve Mitchell, Director, Water Research Commission, Private Bag X03, Gezina 0031, South Africa: tel.: (012) 330 9005; fax: (012) 331 2565 (marked for the attention of Dr S.A. Mitchell or Ms A. Molubi); e-mail: agnesm@wrc.org.za and visit www.wrc.org.za

*Here are some more examples: administrator, boilermaker, ecologist, electrician, chemical and mechanical engineer, geophysicist, laboratory analyst, manager, meter-reader, power plant process controller, researcher, statistician, surveyor, technician, town and regional planner, welder, zoologist.

Quest 1(1) 2 0 0 4 11

Getting to know

SCIENCE

There’s plenty of room for improvement in South Africa’s international S&T ratings. Outreach programmes countrywide are providing remedies.

UWC reaches out The Outreach Project of the School of Science and Mathematics Education of the University of the Western Cape (UWC) gives support in mathematics Chontrelle Kordom explains the use of wild garlic and physical science to pupils from (genus Tulbaghia), a medicinal herb, at Sasol SciFest local township and rural communities. 2004 in Grahamstown. Computer-based teaching and learning Photograph: Courtesy of the UWC SciFest team, Faculty of Natural Sciences aids widen opportunities, and oncampus programmes help pupils How competitive is our S&T education? prepare for examinations. South Africa’s relatively low S&T-related rankings have severe implications for our socio-economic UWC’s Faculty of Natural Sciences development, writes Angeni Bheekie, so it’s important to increase science skills and to encourage children goes further afield to increase science to follow S&T careers. Here is a snapshot of selected rankings that highlight our areas of need. awareness. Since 2002 it has Studies South Africa’s ranking participated each year in the Sasol (the higher the ranking the Scifest in Grahamstown and at better the relative performance) Techno-X in Sasolburg. Third International Mathematics and Science Study (1996): mathematics 41st Its three-dimensional model and science tests (out of 41 countries) illustrates scientific disciplines World Competitiveness Yearbook (2003) including zoology, botany, computer (rankings out of 30 countries with populations greater than 20 million) science, statistics, physics, chemistry, South Africa’s overall competitiveness (2003) 18th community health, environmental and (16th in 2002; 22nd in 1999) water sciences, geology, and Total public expenditure on education as % of GDP 6th biotechnology. Ocean computer (among the best, at 6% in 2001) games, marine videos, and a ‘handsInternet users (82 per 1 000 people in 2002) 18th on’ approach encourage visitors – Qualified engineers available in the labour market 26th young and old – to interact with the (relatively low at 5 per 1 000 of the population in 2003) exhibit and become more aware of Science in schools is not adequately taught (one of the worst) 27th the diversity of science and how it Brain drain (of well-educated, skilled people), hindering competitiveness 28th affects our daily lives. – Angeni in the economy, is relatively high Bheekie (at UWC’s School of Ratio of students to teaching staff in secondary education 28th Pharmacy) (one of the highest at 31:1 in 2000) For details contact Sharon Slinger of the Faculty of Natural Sciences at UWC. Tel.: (021) 959 3891; fax: (021) 959 2266; e-mail: sslinger@uwc.ac.za

Interest in S&T among the youth is low

29th

Figures from IMD (Institute for Management Development) World Competitiveness Yearbook 2003 (Lausanne: IMD, 2003)

Sci-Bono Discovery Centre The first phase of a new science centre development in the old Electric Workshop in Newtown, Johannesburg was opened on 17 March. Sci- (from ‘science’) Bono (TshiVenda for ‘vision’) is what it’s all about – discovering and learning about mathematical, scientific, and technological phenomena. It aims to return “science to society and provide an environment where our children can become enchanted by the wonders of science and technology,” says Sci-Bono CEO Kelebogile Dilotsotlhe. Experience the 90-plus colourful hands-on exhibits. Pluck invisible harp strings to make music. Test your reactions by trying to stop a line of flashing lights. Find out how much fluid you have in your body by standing on a pad and watching surrounding tubes fill with water. Eighteen young and enthusiastic science communicators, each with at least a B.Sc. degree, help you navigate through the science centre, answer questions, and explain exhibits.

12 Quest 1(1) 2 0 0 4

Sci-Bono is a Gauteng Department of Education (GDE) initiative. The GDE has contributed R65 million, with founding partner BHP Billiton contributing R13.5 million towards The real voyage of discovery comes not in a career centre. When the third phase is seeking new landscapes completed in 2006, the R150-million centre will but in having new eyes house exhibition halls, classrooms, laboratories, (Marcel Proust) a career centre, a 350-seat auditorium, a resource centre, a science and technology hub, an education hub, restaurants, and science shops. Schools are welcome to bring groups of youngsters to experience the science centre – just call to make a booking and ask for an information pack. For information: tel.: (011) 832 3363; fax: (011) 832 3360; e-mail: info@sci-bono.co.za; or visit www.sci-bono.co.za Open: Mon–Fri 09:00–17:00; Sat–Sun and public holidays 09:30–16:00.

Genetics& RACE

As we celebrate ten years of democracy, and the transition from apartheid to an integrated yet diverse population, renowned professor of human genetics, Trefor Jenkins, considers the scientific evidence for and against the biological concept of ‘race’ itself. The author with a Nigerian visitor at the Apartheid Museum.

How genetic is ‘race’? From the mid-1750s, geographically separated human populations were, on the basis of their appearance and socalled ‘phenotypic’ features, divided into ‘races’. Distinguishing features include skin colour, facial characteristics, and hair form, and ‘race’ became the established word for ‘biological identity’, explicitly involving a hierarchy of worth. Human genetics has, however, in the last 20 to 30 years, gone far in discrediting the view that Homo sapiens can be subdivided into such discrete genetic ‘racial’ sub-categories. We have discovered that the genes for these iconic features of race, although correlating well with continent of origin, are atypical and do not reflect the genome-wide differences between groups. We need only consider the overwhelming similarities among all human beings with respect to the shape, structure and size of the heart or brain, or whatever, all anatomical features that have been made under the influence of the genes. The superficial differences that seemed to characterize

16 Quest 1(1) 2 0 0 4

different races are, it now appears, accounted for by a remarkably small proportion of the genome – probably less than one per cent. Someone, long ago, said that ‘all humans are the same, under the skin’: recent genetic studies serve to verify this statement.

Evolving human groups Population genetics (the study of genes in populations) has also revolutionized our views on the evolution of humans and the very notion of ‘race’. We have established, for example, that humans are genetically more closely related to the chimpanzee than either is to the gorilla. It was once thought that humans and chimpanzees separated from a common ancestor over 16 million years ago, but genetic studies have reduced this date to only five or six million years ago. Studies of fossil material used to claim that ‘races’ of humankind evolved from more primitive ancestors (Homo erectus), which had themselves been separated, for hundreds of thousands of years, each in a different continent. Caucasoids were thought to have evolved from H. erectus ancestors in

Photograph: Ada Jenkins

Europe, Mongoloids from H. asiaticus (or Peking man) in China, and Africans from H. rhodesiensis in Africa – the latter much later, which would explain their ‘less developed’ nature. Genetic studies of living peoples have changed these views. Almost all students of human evolution now accept that modern humans arose once, in Africa, far more recently than was previously thought – only about 100 000 to 150 000 years ago. Some left Africa about 50 000 to 80 000 years ago and populated the rest of the world. On their way to, and when resident in their new habitats, they adapted to their environments. In this way they became what we now know as Australian aborigines, Mongoloids, and Caucasoids. They replaced any other early species belonging to the Homo genus. Members of a ‘species’ are scientifically defined as those able to interbreed and produce fertile offspring. Our assumption that, in Europe, for example, Homo sapiens replaced Homo neanderthalensis, is based on genetic studies on DNA recovered from fossilised Neanderthals, dated to about

Genetics

RACE &

30 000 years ago. These studies tend to confirm that H. sapiens and Neanderthals could not have produced fertile offspring even if they had succeeded in interbreeding. If groups of a species separate and, isolated from each other, develop in different environments for long enough, they can diverge till they form new species. H. sapiens, however, has never been in that position because humans were always mobile, and perpetuated the gene flow from one population or subspecies to another. It became the most widely dispersed of all known species, because communities survived in the most extreme climatic conditions: they protected themselves against the cold – with clothing – and against the heat through appropriate cultural adaptations. What we regard as ‘racial’ features, then, represent adaptations to different environments rather than anything more fundamental that might lead to divergence. Nazi policies in Germany and apartheid politics in South Africa tried their best to legislate such divergence, but, although ‘races’ often make war, some among them make love. Interbreeding guarantees that their overwhelmingly similar DNA keeps them members of the same human family.

Medical treatment

to heart disease, and a fatal anaemia, called Fanconi’s anaemia, associated with abnormalities present at birth.

What next? The Human Genome Project (HGP) gives scientists free access to what is known of the sequence of the three billion nucleotides (or building blocks) of which it is composed. The Chimpanzee Genome Project, due for completion this year, will facilitate detailed comparisons between the human and the chimpanzee genomes which, we assume, will greatly enhance our understanding of what makes humans unique. We know, already, that humans posses a speech gene which differs by two mutations from the gene that occurs in the chimpanzee. The human form of the speech gene can be dated to a mutation that occurred less than 200 000 years ago but rapidly became fixed in H. sapiens, completely replacing the earlier form of the gene. The HGP will, we hope, lead to dramatic improvements in health care and new drugs, but these may be too

To ignore race and treat an individual as an individual is the spring of justice and the river of hope. because of large-scale migrations through European colonial expansion and the slave trade. For diagnostic purposes, the question is not so much ‘what is my race?’ as ‘what gene pool did my immediate ancestors belong to a few generations ago?’ or ‘what is the history of my population?’ Suites of genetic diseases can occur by chance or, for instance, in populations descended from what were once small, isolated groups. Modern Ashkenazi Jews originate from a Rhine valley population that was isolated and decimated by pogroms in the 9th and 10th centuries. Their descendants have higher frequencies than other populations for conditions such as Tay-Sachs disease and Gaucher disease, affecting the central nervous system and the bones (including the bone marrow), respectively. Similarly, higher frequencies of a suite of conditions occur in South Africa’s Afrikaner population. They include porphyria, high blood cholesterol levels leading

expensive for the developing world to afford. Newly emergent diseases such as HIV/AIDS, SARS, avine ‘flu’ and, since 11 September 2001, the threat of bioterrorism waged by poorer countries against the developed world, are making the latter (for reasons of selfinterest) pay more attention to previously neglected infectious diseases that ravage the world’s poor. “To ignore race and treat an individual as an individual is the spring of justice and the river of hope”, wrote Leigh Van Velen in 1966. Only in this way can we overcome poor race relations. ▲ ▲

How useful is it for a doctor to know a patient’s race? Some medical scientists argue that members of some races may be more liable to suffer from certain diseases than others; and also that members of one race may be more liable than others to suffer adverse or harmful reactions to certain drugs. If such differences are racial, it is in the individual patient’s best interest to be assigned to a particular ‘race’. A contrary view, however, is that ‘racial’ differences are too superficial to be helpful, and that it is far more useful to know the geographical origin of the patient’s ancestors. Take the case of a genetic anaemia, thalassaemia. Common among peoples of the Mediterranean region, India, and South East Asia, it is potentially lethal and the patient might need blood transfusions to stay alive or to develop normally. To confirm the diagnosis at the gene level, we look for a specific mutation.

This helps us to refine the treatment, offer the family genetic counselling, and present the options of dealing with future pregnancies. It is expensive and time consuming to test for all the 20-plus mutations causing thalassaemia when we know that there are a few which are common to each of the geographical regions where the disease occurs. The patient may ‘look’ Indian, or Asian, but if she or he has a parent or grandparent from, say, the Mediterranean region – that is, from a particular geographical area – the medical practitioner can prioritize the investigation and decide which tests to run first. Diagnosis is quicker and more cost effective, and the patient has a better chance of getting the right treatment in the shortest possible time. Geneticists have known for 30 years that most genetic diversity occurs within geographically separated populations (85%) and very little (about 15%) is found between them – most recently, for example,

Further reading: Frank Spencer (ed.), History of Physical Anthropology: An encyclopedia (New York and London: Garland, 1997); Nancy Stepan, The Idea of Race in Science: Great Britain, 1800–1960 (London: Macmillan, 1982); Kenan Malik, The Meaning of Race (New York: Palgrave, 1996). For more on the human genome, read Matt Ridley, Genome (London: Fourth Estate, 1999) and John Sulston and Georgina Ferry, The Common Thread: A story of science, politics, ethics and the human genome (London: Bantam, 2002).

Quest 1(1) 2 0 0 4 17

Genetics

RACE &

▲

For experiences of the old South Africa and a permanent reminder of its institutionalized racism, visit the Apartheid Museum (6 Gold Reef Road, Ormonde, Johannesburg). Open: Tues–Sun 10:00–17:00. Tel. (011) 309 4700; fax (011) 309 4726; and log on to www.apartheidmuseum.org Contact the non-governmental organization, the Centre for Anti-Racism and Anti-Sexism (CARAS) at www.caras.org and other organizations with similar missions for dialogue concerning the roots of racism and ways in which South Africans can overcome it and work together for the growth of a truly non-racial society.

A class of children in a South African school a decade after the end of apartheid. Photograph: Courtesy of the Principal of Parkview Senior School, Johannesburg

‘Race’ in science In the 5th century bc, Herodotus travelled around the Mediterranean and south along the Nile to Aswan and, observed anthropologist C. Loring Brace (1997), never once grouped people he met in terms equivalent to what we would today call ‘races’, that is, as “divisions of humankind, having certain physical peculiarities in common”. The medieval Italian Marco Polo (1254–1324) journeyed from Venice to China and back via Asia and India; the great Islamic geographer Ibn Batutah (1304–1377) visited the Balkans, southern Russia, the Middle East, North and East Africa, India, South East Asia, Gibraltar, and Spain, and crossed the Sahara to Timbuktu and West Africa. Both described skin colour and appearance of people they encountered, but categorized peoples by culture and religion only – as ‘idolators’ or ‘infidels’, for instance – not in categories grounded in physical appearance. There seems no general term for ‘race’ in the modern sense before longdistance ocean travel began in the mid15th century. Travellers overland, largely on foot, could cover a maximum distance of some 40 km each day, which, perhaps, rendered imperceptible the gradation of one group of people into another, even to astute observers. Brace suggests that voyages of discovery made mariners aware of striking differences in skin colour, head shape, facial features, and hair form between different populations. In 1758, Linnaeus classified Homo as four sub-species: H. sapiens

europeus, H. sapiens afer (West Africa), H. sapiens asiaticus (Indonesia) and H. sapiens americanus (NE North America). Blumenbach, a German medical doctor and a comparative anatomist, distinguished in 1775 between people of SE and NE Asia. He named his collection of European skulls ‘Caucasoid’ because those from the Caucasus mountain regions were ‘beautiful’, the most perfectly formed specimens, implying superiority. Other late-18th century scientists described non-Caucasoid races as ‘degenerations’ of the species after leaving the Garden of Eden, inferring a ‘hierarchy of worth’ to the races of H. sapiens, with Negroids (or Africans) at the bottom. We can describe the biological anthropology practised by American and western European scientists, throughout the 19th century and the first half of the 20th, as obsessed with race, entrenching a scientific racism shaken off only after the excesses of Nazi anthropology were exposed. Prejudices against fellow citizens belonging to other races or population groups are, wrote Nancy Stepan, “relics of a past deep psychological need of Western Europeans, scientists among them, to divide and rank human groups, and to measure them negatively against an idealized, romanticized picture of themselves”. ■ Emeritus Professor Trefor Jenkins is at the Department of Human Genetics, National Health Laboratory and the University of the Witwatersrand, PO Box 1038, Johannesburg 2000.

‘Race’ in English According to the Oxford English Dictionary, the term ‘race’ originally highlighted groupings of persons, animals, or plants connected by common descent or origin. Narrower modern uses of ‘race’ to distinguish groups of humans by physical characteristics began, apparently, only in the late 1700s. Examples of the meanings of ‘race’ at different times: ■ Offspring, descendants: the “race and stocke of Abraham” (1570) ■ Tribe, nation: “Llewelyn ap Gruffith, last Prince of Wales of the British race” (1600) ■ All humankind: “From among the humane race [thou shalt] Roote out their generation” (1580) and “the whole race of Mankinde” (1600) ■ Group of persons with something in common: “a rase of worthie learned gentlemen” (1568) and “a race of Bishops” (1570s) ■ Particular variety of a species, breed, or stock (including animals and plants): “of all the races in Graece, the horses and mares of Thesalia are most celebrated” (1580) ■ Divisions of humans with physical characteristics in common: “The second great variety in the human species seems to be that of the Tartar race” (1774) and “Considerable differences occur in the general stature of the several races of mankind” (1839) ■ Groups of tribes or peoples forming a distinct ethnic stock: “No two races [of people] can be more strongly contrasted than the ancient Egyptians and the Syro-Arabian races” (1842).

18 Quest 1(1) 2 0 0 4

Surveying South Africa’s

R&D Photograph: Himla Soodyall

Preliminary results from the latest 2001/02 Research and Development survey have been made public. What do they say about our progress?

Africa’s health The 2nd Annual Conference of the Africa Genome Initiative (organized by South Africa’s Human Sciences Research Council and Cairo’s Ain Smans University) was held in Cairo from 26–29 March 2004, at the Mena House hotel, in the shadow of the Great Pyramids of Giza. Over 200 delegates from 12 countries attended (142 from Egypt, a few from Ethiopia, Kenya, Libya, and Morocco; 33 from South Africa; 16 from the UK; 13 from the USA). The emphasis was unashamedly on genomes and Africa. Topics included: ■ the ‘genocentrism’ fallacy (i.e. that social life is significantly controlled by genes) ■ sharing international health research benefits; protecting/ benefiting communities in developing countries ■ genetic ancestry; threats from new biotechnology practices, including genetic modification of organisms ■ society’s role in monitoring possible excesses of modern science ■ tracing human movements within and out of Africa (via anthropology, genetics, archaeology, linguistics) ■ threats to continuing existence of small indigenous human populations ■ the place of African researchers in using biotechnology to address the continent’s agricultural and health needs ■ the need to integrate technological advancement and scientific approaches in the African context and to accept responsibility for their social consequences ■ contribution of genetic studies in defining the time and place of the domestication of cattle, sheep, goats, and chickens and their subsequent movements within Africa. – Trefor Jenkins For details visit www.africagenome.co.za

esearch and development (R&D) adds value to South Africa’s resource-rich wealth – to what comes from nature, such as minerals, metals, and marine life, and to the production of basics, such as food. To discover what the country spends on R&D and what the investment means, the Department of Science and Technology commissioned a survey and presented preliminary results to parliament in January 2004.

R&D and GDP One indicator of the competitiveness of a country’s economy is the gross expenditure on R&D expressed as a percentage of its gross domestic product (GDP). South Africa’s stated objective is, by 2005, to double government spending on science and technology (S&T) and to reach an expenditure target of at least 1% of GDP. Progress is being made: South Africa in 2001/02 spent about R7.5 billion, that is, 0.76% of GDP – up on the R4.1 billion or 0.69% of GDP in 1997/98. In the latest survey, Gauteng accounted for more than half (53.7%) of the country’s R&D expenditure, followed by the Western Cape (15.1%). To put the figures into an international context, Israel tops the world list at 4.81% of GDP. Singapore and Chinese Taipei (Taiwan) spent 2.13% and 2.16% of GDP on R&D in 2001, respectively. China spent 1.09% (up from 0.6% in 1995) and the Russian Federation 1.16%, whereas Argentina spent 0.42% and Romania 0.4%. The figure for the USA in 2001 was 2.82%. The average for the then 15 European Union countries was 1.93%: their goal is to reach an average R&D expenditure of 3% of GDP by 2021.

Spending profile William Blankley and Michael Kahn conclude that “South Africa’s R&D profile is fairly evenly distributed in areas of strategic and socio-economic importance.” Most of the country’s R&D was conducted on behalf of manufacturing (12.2%). Advancement of knowledge in the natural sciences, technologies, and engineering accounted for 13.2%; the field of mineral resources, excluding energy, 11.1%; and social upliftment (including health, education and training, and development-

based community services) for 12.6%. The major fields of R&D spending in South Africa were: the natural sciences (22.2% of spending), engineering sciences (20.2%), applied sciences and technology (15.2%), information and communication technology (13.7%), social sciences and humanities (10.7%), medical and health sciences (10.1%), and agricultural sciences (9.3%).

The researchers The country has relatively few full-time equivalent (FTE) researchers: 35 704 in all, or just 1.88 per 1 000, but nonetheless a substantial increase over 1997’s 0.71. ‘FTE researchers’ are defined as researchers, postgraduate research students, technicians, and support staff. Of these, 34.9% are women (compared to Japan’s 10.7% and Norway’s 28.2% – and Argentina’s 49% and Russia’s 44%). Progress has been made towards achieving greater equality in the R&D workforce: the proportion of personnel from previously disadvantaged population groups working at science councils now stands at 45.9% (or 36.5% of the total number of research workers), compared to 7.3% just ten years ago.

The sectors The survey covered four main sectors of South Africa’s R&D: business (responsible for nearly 54% of the country’s total R&D), government (21.1%, including the eight science councils), higher education (25.3%), and the non-profit sectors. About 7.3% of South Africa’s R&D is funded from abroad, while 30.1% is funded by government. Applied research and experimental development is the focus of research in business (82%) and higher education (52%). Higher education also performs about 48% pure and strategic basic research, which is important in providing skills and training. ■ The 2001/02 Research and Development (R&D) Survey was undertaken by the Knowledge Management Group of the Human Sciences Research Council. For details visit www.sajs.co.za and read William Blankley and Michael Kahn, “South African research and development: preliminary results and indicators from the latest survey,” South African Journal of Science, vol. 100, no. 1–2 (2004), pp. 9–11. This QUEST summary is drawn from their report.

Quest 1(1) 2 0 0 4 19

Getting the numbers right How do we calculate the numbers of people affected by HIV and AIDS? We report on issues facing those with the thorny task of quantifying the problem. recise, up-to-date figures on South Africa’s HIV infections and AIDS-related deaths are not available, but the data we have tell us the problem is serious. How convincing are the statistics? We asked UK-based mathematician Ekkehard Kopp and World Health Organization (WHO) epidemiologist Brian Williams to explain, and we consulted recent research published in the South African Medical Journal.

What we know South Africa has the greatest number of people infected with HIV of any country in the world. They can expect to live for about 10 years on average, although some will die within two years of infection and some may live for 20 years after infection. Antenatal clinic data graphs show the proportion of those infected with HIV rising from 0.7% of South Africa’s total population in 1990 to 24.5% in 2000 and now, apparently, levelling. “These are not guesses,” insist Williams and Kopp: “South Africa has perhaps the most complete database on HIV in the world.” We do, however, have information gaps, and work is needed to make the models more precise. In April, a team mainly from the Western Cape (the Medical Research Council’s Debbie Bradshaw and Ria Laubscher and the University of Cape Town’s Rob Dorrington and David Bourne, with Ian Timæus from the London School of Hygiene and Tropical Medicine) published a scientific letter in the South African Medical Journal, analysing patterns of adult deaths in South Africa and estimating those that are AIDS-related. Using available studies and databases, they found that the age pattern of death rates had changed rapidly in six years in a way that is “consistent with the heterosexual HIV/AIDS epidemic”. In specific age groups, in other words, the proportion has changed of deaths due to HIV, TB, pneumonia, and diarrhoea – all indicator conditions of AIDS. Here are some of their key findings:

20 Quest 1(1) 2 0 0 4

• the number of adult deaths on South Africa’s population register increased steadily by 68% during the 6-year period between 1998 and 2003 (some 12% of which could be due to population growth, and under 10% to improved post-apartheid registration of persons on the register of population and of deaths): this leaves a real increase of more than 40%; • the number of registered deaths among women aged 20–49 years increased by 190% over the same period, which corresponds to a real increase of more than 150% once population growth and possible improvement in registration are accounted for.

“Even the most affluent and cohesive society would face serous threat from a fatal disease affecting a quarter or more of its most productive age group,” observes Kopp, “especially when it remains largely symptomless for much of its long infective period. The challenge for South Africa is to optimise the impact of prevention measures to stem further infection, and to give effective treatment to the 5 million of its citizens who are already HIV positive. This dual task requires understanding the disease at many levels.” The most useful mathematical models for such understanding combine the ‘what?’ questions with

Shifts in the figures mean more precision as more data become available – that is how science works. Because AIDS does not always appear on death certificates, assessing the number of AIDS-related deaths means tracking the number of deaths from all causes, and using “alternative approaches such as modelling the epidemic” so as “to obtain reliable estimates of the real number of deaths due to AIDS.” The authors conclude that “The uncertainty about the precise number of AIDS deaths should not allow people to dismiss the impact of HIV/AIDS on mortality.”

How mathematical models work Mathematical models are not products so much as processes. Estimating the numbers and calculating the potential effects of plans to deal with the HIV/AIDS pandemic is the business of experts such as epidemiologists (who study the incidence and distribution of diseases and other factors relating to health) and actuaries (who use the mathematical laws of probability to measure risk and to make forecasts about the future), working with authorities including economists, molecular biologists, clinicians, and other health professionals and social scientists.

the ‘why’s’. Factual starting points then point to the further question – ‘why is this so?’ Answers to the ‘why?’ questions give clues as to how to improve the dynamics of the models we use, because they keep telling us more about the key factors affecting the rates of change in the epidemic. “The purpose of models is not to fit the data but to sharpen the question,” is Williams’s favourite modelling quotation, because models “determine what further studies will add significantly to our understanding of the bigger picture.” To be able to say ‘we think this is how it works’ means linking statistical modelling at macro (population) levels with that at individual/host level and at the cellular (molecular biology) level. Modelling HIV and AIDS, therefore, means devising complex models that address complex questions, says Kopp: “We don’t have full understanding of the dynamics of the disease and how it spreads, so we try to improve the models all the time. We operate on the best information available at the time. Shifts in the figures mean more precision as more data become available – that is how science works.”

HIV/AIDS – GETTING THE NUMBERS RIGHT

Where are the gaps?

Having enough of the right data to hand is one thing; reading it correctly is another. Ideally, we should determine HIV prevalence in the general population from community-based studies, but few have been conducted because of logistical and financial difficulties and ethical considerations. National and international studies for Africa, therefore, depend heavily on data from antenatal clinics, which remain the most accessible HIV prevalence data sets on the continent, and our only comparative measure of the spread of the disease. Reading the data correctly means understanding what they can and cannot tell us. Antenatal clinic studies show us overall trends in prevalence over time, for instance, even though they do not provide data on men, and it is not easy to determine precisely how rates among the women attending these clinics compare with rates among women in general. Despite limitations, however, the data inform us about women who are sexually active, and the clinics themselves are definable and accessible. Blood is drawn from those attending these clinics to test for syphilis, and leftover blood samples may be used anonymously for HIV testing. Identifying the gaps in the available data does not mean that the data are unusable, but that they need to be interpreted in sophisticated ways and constantly corroborated. Comparing prevalence and mortality is an example of data interpretation that needs care, says Kopp. Prevalence needs to be linked with mortality data of about 10 years later, because of the time lag of the disease between infection and death. Those infected in 1990–92, when the antenatal clinic prevalence rates were 1–2%, for instance, would be at peak risk of dying around the year 2000. With an estimated peak prevalence in 1998 or so of 25–28%, we expect the resulting peak mortality rates (without the intervention of antiretroviral (ARV) drug regimes) to appear between 2008 and 2010. “Current antenatal clinic data may show a lowering of the rate of new infections,” he concludes, “but this, unfortunately, does not mean that the epidemic is on the wane. Prevalence rates are what models need to take into account – in southern Africa, these remain by far the highest in the world.”

Models are only as good as the data on which they are based and against which they are tested, so, inevitably, in the absence of precise figures, estimates will vary. All the available studies, however – the two computer models used by the Actuarial Society of South Africa (ASSA), ASSA 600 and ASSA 2000, and Epimodel, used by UNAIDS – predict the same trends. It would help, say researchers across the board, to have better access to the most recent data held by government departments and private sector groups. By April 2004, for instance, “the most recent year with full officially published [death] statistics was 1996”, observe the authors of the study on adult deaths published in the South African Medical Journal. Although South Africa has gathered antenatal clinic data on HIV infections and undertaken large-scale household surveys, the raw data used by government for policy responses is often not available to researchers. It would also help to conduct further studies based on questions arising from existing data. Williams gives the following example. “No-one has any idea as to why the prevalence of HIV in north India is 0.2% and steady or even declining, and in South Africa it is 20%: a 100-fold difference. My guess is that migrant labour and the mines have something to do with it.” Kopp agrees: “It seems clear that the incessant need for cheap labour in the mines plays a major role, but migratory practices haven’t been incorporated into the models since no-one knows how to. In the meantime we would benefit from confidence intervals in our models, and only a few have that facility.” Calculating the effects of HIV and AIDS over time is another key issue. “It helps,” says Williams, “that we know how the prevalence has changed over time. However, the key parameter is how long people live after being infected with HIV. After 20 years and billions of dollars, there is still only one study in the entire continent of Africa (in Masaka, Uganda) that attempts to measure survival in a cohort which had about 3 000 people 12 years ago, of whom fewer than half are still alive. Ten or twenty survival studies in different settings would at least give us a picture of how long people live with AIDS and what kind of infections they get while they are infected. The lack of studies is criminal.” Kopp’s wish list continues: detailed

and extensive studies in sentinel sites to measure behaviour, other sexually transmitted infections, and what happens once people become HIV positive. “Infection with opportunistic diseases varies greatly – people become weaker, lose their appetite, become increasingly vulnerable to skin or respiratory diseases and, later, to heavy diseases like TB. Our understanding of the key factors that drive the highly differentiated spread of the infection remains incomplete. We need a better quantitative understanding to underpin policy and treatment responses.”

Implications of South Africa’s rollout Although there is no cure for AIDS, ARV drug regimes provide the means to slow its impact and buy time for patients and society to adapt and to find ways to cut transmission, says Kopp. ▲ ▲

Reading the available data

Definitions Prevalence: the proportion, out of a total population, of infected people at a specific time. Incidence: the number of newly infected people in a given period. Confidence interval: a measure of the confidence that one may have in the probability that a statistical estimate is accurate. If an estimate is made of, say, 23%, how confident are we that the correct figure lies between 22% and 24%? The aim is for narrow confidence intervals and for confidence intervals to be stated where possible. Sentinel sites are representative sample groups studied in specific places over time. ARV drug resistance occurs because HIV goes through hundreds of thousands of mutations daily. Some die and some may be resistant to antiretroviral drug treatment. If the resistant mutations multiply sufficiently, the effect of treatment is reduced. Some ways to reduce HIV transmission ■

Vaccine development

■

Treatment of sexually transmitted infections

■

Male circumcision

■

Education for behavioural change

■

Use of condoms and microbicides

■

ARV drug regimes

■

ARV rollout.

People at high risk ■

Migrant workers and truck drivers

■

Poor people living in informal urban settlements

■

Women aged 15–30

■

Sex workers

■

People exposed to violent sexual contact

■

People employing practices such as drying the vagina before intercourse.

Quest 1(1) 2 0 0 4 21

HIV/AIDS – GETTING THE NUMBERS RIGHT

The SACEMA initiative harnesses the diaspora Conceived by the Department of Science and Technology (DST) as a Centre of Excellence project in an area of urgent national need, the South African Centre for Epidemiological Modelling and Analysis (SACEMA) initiative brings experts together from around the world – many of them brought up in South Africa – to develop epidemiological modelling that addresses problems of immediate relevance to Africa and to produce reliable results rapidly. From 8–13 December 2003, SACEMA’s workshop on AIDS modelling, with over 60 invited participants from a wide spread of disciplines, was opened by Dr Adi Paterson, now the DST’s deputy director-general. It brought together researchers active in modelling the impact of HIV/AIDS. Participants presented biological and mathematical modelling perspectives in host-viral dynamics. They reported on the implications for implementing the rollout of ARV treatment, and for better clinical management of HIV and AIDS. Visit www.stias.ac.za/sacema for the Workshop presentations. For more on SACEMA, visit www.aims.ac.za/SACEMA or e-mail the convenor of the SACEMA executive, Professor Ekkehard Kopp, at p.e.kopp@hull.ac.uk ▲

Life expectancy for infected people and, crucially, quality of life, is transformed for most patients on ARVs. “If the mean is around 8–10 years without them and 18–20 with ARVs taken properly, then using the drugs effectively will help enormously in containing the AIDS orphan issue, and enabling people to fend for themselves while living with AIDS,”

says Kopp. “ARVs lower the viral load so dramatically that infected people on the drug therapy are less infectious themselves, and less likely to pass on the infection to others. The hope that the rollout brings will also encourage people to have themselves tested. These benefits bear repeating over and over.” South Africa’s ARV rollout plan makes it essential “to monitor carefully the levels of compliance, outcomes, survival, and other infections, especially TB,” warns Kopp. “Better figures will demand ever better mathematics.” Take the matter of precise adherence to the complex drug regime, for instance, and the specific diet regimens that are needed. With 100% adherence the likelihood of drug-resistant mutations is least. Adherence of 95% is needed to suppress the virus. At lower levels, the risk of side effects, and of developing resistance and secondary diseases increases. The international view has been that Africans in resource-poor settings will have poor adherence, which may decrease the efficacy of ARV therapy as a whole. Two independent studies in Africa show an adherence of 93%, however, indicating not only high compliance in these African groups but showing

them to be “often more adherent than western patients” (SACEMA report). Combined understanding of mathematics and biology, Kopp believes, will lead to better understanding of the way HIV infects a particular host and attacks the immune system, which in turn will lead to better tools for clinical management of HIV: “With the danger of resistant strains, careful monitoring together with mathematical modelling can help reduce the potential rate of drug resistance.” Understanding the complex modelling processes helps us better to understand the limitations and quality of information that models provide. “The imminent rollout of ARV treatment adds urgency to the need for all to join hands to fight this epidemic,” say Williams and Kopp, “and mathematics has a central role to play.” ■ This report was based on interviews with Ekkehard Kopp (Pro Vice-Chancellor at the University of Hull in the UK) and Dr Brian Williams, WHO epidemiologist in Geneva; the preliminary report on the proceedings of the SACEMA workshop in December 2003; and the article by Debbie Bradshaw, Ria Laubscher, Rob Dorrington, David Bourne, and Ian Timæus, “Unabated rise in number of adult deaths in South Africa”, South African Medical Journal, vol. 94 (April 2004), pp. 278–279. For details on the economics of treating HIV and AIDS, read Nicoli Natrass, The Moral Economy of AIDS in South Africa (Cambridge: Cambridge University Press, 2004).

for treating HIV and AIDS Anthony MBewu, who chaired the Minister of Health’s Taskforce that prepared South Africa’s comprehensive plan for HIV and AIDS, tells us what the thinking was behind it and how it intends to succeed. n 18 November 2003, South Africa’s cabinet endorsed its national Operational Plan for the Comprehensive Treatment and Care of HIV and AIDS. To understand, we need to return to the early 1980s, to the beginning of this devastating epidemic, when the sudden emergence of this new ‘plague’ in gay young men in New York and San Francisco shocked the world. Invariably fatal, a veritable ‘Andromeda strain’, the disease killed most of those infected within 12 months of diagnosis. As a medical student in London, I saw one of our senior physicians fall sick, grow thin, and die within barely two years. Even then, the stigma surrounding this disease was profound.

22 Quest 1(1) 2 0 0 4

Controversy continued over whether the American Robert Gallo or the French scientist Luc Montagnier (and his team that included Barré-Sinoussi) had discovered the infectious agent that causes AIDS – the human immunodeficiency virus (HIV). Breakthrough came in the 1990s with the introduction of cotrimoxazole treatment and prophylaxis for Pneumocystis carinii, the organism that was then causing the pneumonia responsible for most AIDS deaths in Europe and America. Overnight, a uniform annual mortality of 90% fell to below 50%. Later, the discovery that treating AIDS patients with isoniazid would prevent them from getting tuberculosis (TB) similarly

revolutionised care in the developing world, where TB is the commonest single cause of AIDS-related death. Finally, interventions such as multivitamins, prompt management of other opportunistic infections, treatment and prophylaxis of candidal fungal infections with fluconazole, and management of concomitant sexually transmitted infections (STIs) would ensure that, by 2000, annual mortality without antiretroviral (ARV) therapy was reduced to 25% per annum. Until recently, these were the only public health treatments available for most South Africans with AIDS. They also took traditional and complementary medicines; received psychosocial support from civic and

HIV/AIDS – SOUTH AFRICA’S PLAN

religious groups; and attempted to ‘live positively’ with HIV through diet, exercise, and a positive mental attitude. Many altered their sexual practices to prevent reinfection with HIV or other STIs and to protect partners from HIV infection. ARV therapy was deemed unaffordable by government for, till five years ago, it cost US$12 000 per patient per year. From 2000, however, a spectacular collapse in the price of ARV drugs was triggered by pressure from public health activists on the pharmaceutical industry at home and abroad, and by the court action the South African government won against ‘big pharma’ in 2000. After that, prices of ‘triple therapy’ fell in 2003 to US$120 per patient per annum – less than 1% of the 1999 cost – and the pharmaceutical companies could still make a small profit. Against this backdrop, South Africa’s government in April 2002 commissioned a costing study by a team from the departments of Health and Finance to investigate the introduction of ARV drugs into the

number of such potential patients will rise from 400 000 in 2003 to over one million in 2008. The cost, the Taskteam estimated, would be an additional R4.4 billion a year by 2008 – equivalent to more than 10% of the entire 2003 public sector budget. Of this, R1.67 billion a year would be spent on ARV drugs and R670 million on nutritional supplementation. Such comprehensive treatment could add, on average, between two and five years to the life of someone living with AIDS, but estimates are notoriously difficult to make, as, for ethical reasons, treatment can never be compared to ‘placebo’ controls; treatment regimens constantly change; adherence to treatment protocols can be difficult, resulting in dropout; toxicity and longterm side effects are common; and emerging viral resistance to the drugs necessitates regimen switches. The Plan therefore includes a large research component, to investigate ways to mitigate operational challenges and to seek new treatments for this incurable disease. It includes monitoring and

If South Africa’s Plan succeeds, it will be the world’s largest and most rigorous national treatment plan for HIV and AIDS. All sectors need to be mobilized and efforts to prevent HIV infection need to be further developed. public health sector. A further Taskteam was appointed by the Minister of Health in August 2003 to prepare the detailed Operational Plan for the Comprehensive Treatment and Care of HIV and AIDS, which cabinet then endorsed in November. The Plan adds ARVs to the therapies already existing in the public sector. Its three primary facets include ARVs, nutritional supplementation and, for patients who choose to access these from traditional practitioners, traditional and complementary medicines. Government undertook to ensure that, within one year of the first drugs arriving in public hospitals, all 53 districts in South Africa would have at least one service point providing this treatment – a stipulation emanating from the right to equitable access to healthcare enshrined in the Constitution. Government undertook, within five years, to make such treatment available within each of the several hundred of the country’s municipalities – ensuring that, by then, every South African living with AIDS and needing treatment would have access to it. Projections estimate that the

evaluation mechanisms, IT-based patient information systems, and pharmacovigilance systems. Guiding the Plan is the principle that this enormous investment of scarce resources in a single disease should bring improvements to the entire national health system – such as additional trained doctors, nurses, and pharmacists, as well as clinics and laboratories. The investment would thereby address other health problems such as TB, heart disease, stroke, hypertension, diabetes, and violence – which together account for at least 75% of annual deaths, illness, and injury. The investment would also help build South Africa’s pharmaceutical industry, as the ARVs would be manufactured here. The first patient in the government programme began treatment in January 2004. Already, 112 service points have been accredited to deliver therapy, with approximately 2 000–3 000 patients already receiving ARVs through 25 service points. In May, in his State of the Nation address, President Thabo Mbeki declared that all 112 service points would be providing therapy by

March 2005 to over 53 000 people, more than the 40 000–50 000 patients currently on ARV therapy in the USA. Tenders for bulk supply of ARVs went out in February 2004, with 10 companies shortlisted to manufacture locally with active pharmaceutical ingredients (APIs) imported from India and China. Some will involve manufacturing under licence with ‘big pharma’, others in joint ventures with foreign generic manufacturers. The Medicine’s Control Council has ensured that, of the 15 or so ARVs already registered with it, several are now registered in their generic form through a fast-track mechanism. If South Africa’s Plan succeeds, it will be the world’s largest and most rigorous national treatment plan for HIV and AIDS. All sectors need to be mobilized, including government and the civil service, health professionals, volunteer and non-governmental organization workers, community and religious leaders, the pharmaceutical industry, as well as patients and their families – within the ambit of the National Strategic Plan for HIV and AIDS. Furthermore, the already extensive efforts to prevent HIV infection, especially behaviour change, need to be further developed and strengthened as the only means by which the epidemic can be halted. ■ For the Operational Plan for the Comprehensive Treatment and Care of HIV and AIDS, see Department of Health at www.gov.za Professor Anthony D. MBewu is Acting President of the Medical Research Council.

ASSAf on HIV/AIDS – lethal virus and serious problem The first public statement issued by the Academy of Science of South Africa concerned HIV infections and their invariable end-stage, AIDS. Researchers conducting laboratory work on this virus and the diseases it causes are amazed by the complexity of the mechanisms by which HIV establishes infections and then evades destruction by the normally very effective defensive immune systems, as well as counteracting drugs developed to kill it or to stop it from multiplying in its human hosts. Clinicians and public health specialists are similarly amazed at the amount of scientific knowledge they require to prevent infections and treat patients progressing to full-blown AIDS. The ASSAf statement on AIDS highlights the multidimensional nature of the massive HIV problem in South Africa, and recommends urgent mobilization of science and technology expertise to understand and investigate the disease in this country; to generate and test vaccines and new drugs; and to develop an indigenous drugmanufacturing capacity that can affordably cope with the needs of HIV-infected people and enable them to live normal private and working lives, to look after their children, and to sustain the country’s economic base. For the full text of the ASSAf statement on AIDS visit www.assaf.ac.za

Quest 1(1) 2 0 0 4 23

Quest for our

– the fossil story Ron Clarke tells us what the 4-million-year-old Australopithecus skeleton he found in the Sterkfontein caves five years ago says about our origins. earching for our earliest ancestors, we have tried to find their fossil remains and to formulate theories and concepts based on our finds. We have predicted where we would discover these fossils and imagined what our human ancestors looked like, and how they moved and behaved. Some of the early scientists foretold with great accuracy what later discoveries continue to reveal.

or Miocene, or yet more ancient? In still older strata do the fossilised bones of an ape more anthropoid or a man more pithecoid await the researches of some unborn palaeontologist?” Succeeding generations would succeed in fulfilling his expectations. Eugene Dubois – only five at the time of Huxley’s comment – would discover “a man more pithecoid” in Java in 1891. He named it Pithecanthropus erectus, the erect walking ape-man.

Out of Africa

Man-apes

In 1774, in his Origin and Progress of Language, James Burnet (Lord Monboddo) of Scotland wrote, “From the South Sea, I will come back again to Africa, a country of very great extent; in which, if it were well searched, I am persuaded that all the several types of human progression might be traced and perhaps all the varieties of the species discovered.” Written almost a century before Darwin’s work on evolution, this remarkable prediction was fulfilled when, in 1924, the child skull of Australopithecus was discovered at Taung, near Kimberley in South Africa. Many more discoveries relating to human evolution in various parts of Africa have since been made. In 1863 T.H. Huxley also foresaw the possibilities in Man’s Place in Nature and Other Essays: “Was the oldest Homo sapiens Pliocene

Coming down from the trees with an upright posture. Sketch: Ron Clarke

The discovery of an “ape more anthropoid” was to be the destiny of two researchers working in South Africa – Robert Broom (born in 1866) and Raymond Dart (born in 1893). Dart discovered and named Australopithecus (the southern ape) from Taung, and Broom, in 1936, discovered the first adult Australopithecus, which he later named Plesianthropus (meaning ‘near man’) from Sterkfontein, and, in 1938, Paranthropus (meaning ‘parallel to man’) from Kromdraai, near Sterkfontein. These early South African hominids were considered by their discoverers to be apes on the way to becoming humans – an ancestral human relative with a mixture of human and ape characteristics. It was thought that these ‘ape-men’ living in Africa must be closely related to chimpanzees and gorillas and that, if this were the case, the ‘ape-men’ must have gradually developed their upright posture from an original walking position on all fours (quadrupedal). This concept is still depicted in logos, cartoons and advertisements based on an original developmental sequence that appeared in F. Clark Howell’s popular Time-Life book, Early Man (1965).

Up from the apes In 1932, however, long before this scenario of evolution of uprightness had developed, Harvard anthropologist Earnest Hooton offered a very different explanation. His book, Up from the Ape (1931), noted that “the way a primate progresses on the ground seems predetermined by the bodily adaptations effected by its posture and the method of locomotion in the trees.”

24 Quest 1(1) 2 0 0 4

Photographs: Kathleen Kuman

He considered that the human ancestor sat upright and progressed in an upright manner in the trees; when its ancestor descended to the ground, therefore, it did so keeping a similarly upright position and then walked on two legs, not four. Such an ancestor, Hooton postulated, would not have had excessively long arms and its legs would have been relatively long and strong, though shorter than those of later humans. It would not have had the massive jaws and thorax of the gorilla and orang utan, but jaws, though larger than those of humans, probably no bigger than those of a chimpanzee. Its brain would have been relatively small. This description of a prehuman ancestor was an uncannily accurate prophecy of adult Australopithecus fossils that were later discovered.

A very important discovery

found that 10 of them fitted perfectly to form a hominid lower leg and partial left foot, which, remarkably, had a slightly divergent big toe that would have been useful in tree climbing. Two other bones were from the right leg and foot. One of these, a portion of right shinbone, provided the vital clue that led to our search for the whole skeleton in one of the lowest infills in the Sterkfontein caves. It had broken off when limeworkers had blasted in the Silberberg Grotto in the early 1930s. I knew that the piece of shinbone in the box had come from their debris. I realized that the rest of it had to be in the unquarried rock and that, if we could find the matching exposed piece – in cross section about the size of a R5 coin – it would lead us to the remainder of the skeleton still embedded in the rock. The cave was the size of a barn, without natural light, dusty, with uneven walls and floor. The two men who searched the cave, Stephen Motsumi and Nkwane Molefe – after just one-and-a-half days of searching – found what we were hoping for: the perfect contact between our piece of shinbone and a tiny exposed section of bone in a slope of ancient infill. Five years of painstaking excavation have so far have revealed the legs, crushed pelvis, lower lumbar vertebrae, scattered ribs, a complete skull, the complete left arm and hand, and now, six months ago, the right elbow region and broken and displaced right forearm, with some wrist and hand bones. Work continues with the aim of uncovering more of the right hand and wrist, the upper right arm, the upper vertebrae, the shoulder blades, and the collarbones.

A unique primate From 1936 onward, the caves at Sterkfontein, and at nearby Kromdraai and Swartkrans, have been

Why the Sterkfontein skeleton is important ■

For the first time we are able to examine a proven association between limb bones and skull type, because we know for certain they belong to the same skeleton. (Past discoveries of limb bones and skull found close to each other on a site were no proof that they belonged to one individual, particularly in a cave where many individuals are mixed together in an infill.)

■

The proportions of upper and lower limbs can be directly compared. (This information will tell us more about the evolutionary processes of the way we move.)

■

The completeness of the skeleton tells us something about the way it died. It was not killed and eaten by carnivores, but must have fallen or climbed into the cave, died probably from starvation or injury, was mummified in dry conditions, and then subsequently sealed in during a long wet phase by a thick stalagmitic flowstone.

■

The skeleton was, in April 2003, dated to about 4 million years ago by a recent technique called Buried Cosmogenic Nuclide Dating, and other factors also point to this as a reasonable date. The great depth of the skeleton within the cave system, for instance, with the thick sequence of infills and stalagmite flows above it, indicates that this fossil has to be older than the 2–3-millionyear-old fossils from much higher up in the sequence.

▲ ▲

At the end of his 1925 article about the Taung child, “On the newly discovered South Arican man-ape”, Robert Broom wrote, “It seems to me not at all improbable that an adult Australopithecus will yet be obtained, and possibly a perfect skeleton. Should such a discovery be made, it would be difficult to overestimate its importance.” Seventy-three years later Broom’s hope was realized and the complete adult skull and complete skeleton were discovered at Sterkfontein in 1998. They surpass Broom’s anticipation of their importance and, we believe, also demonstrate the accuracy of Hooton’s concept of the prehuman ancestor. As befits the title of this magazine, the quest for the skeleton began thanks to my chance discovery, of 12 Australopithecus foot and leg bones from Sterkfontein that had lain in boxes for 14 years, wrongly identified as animal bones. When I started putting them together I

Left: The skull of the 4-million-year-old Australopithecus adult (StW 573) as found face down at Sterkfontein. It has human-like teeth with relatively small canines, a massive cheekbone, and a small, ape-like brain. Apart from the skull of the Taung child, found in 1924, this is the only complete one of an australopithecine ever found where lower and upper jaw are articulated and belong to the same individual.

Quest 1(1) 2 0 0 4 25

Agreement between government and landowners On 4 March 2004, an agreement was signed between government and the landowners of 13 fossil sites in Gauteng’s Cradle of Humankind, to achieve a balance between preservation of these important areas and public access to them. Plaques were also unveiled at two of the sites: at Sterkfontein and Motsetse. This World Heritage Site holds a remarkable record of the early stages in human evolution. The shared commitment of government and landowners will help to protect and enhance the area in which scientists continue to explore our origins and the ancient environments that have shaped us. For more information contact Anthony Paton, Education Officer: Cradle of Humankind World Heritage Site, tel.: (011) 355 1462 or e-mail: anthonyp@gpg.gov.za or visit www.cradleofhumankind.co.za

▲

providing fossil clues to the fascinating story of human ancestry. Many isolated skull and limb bone fossils of Australopithecus have come from Sterkfontein excavations, and many of Paranthropus from Swartkrans, with a few scarce fossils of early Homo from Swartkrans and Sterkfontein. All have inspired numerous studies and hypotheses based on a limited concept of the whole body. Now, Sterkfontein’s complete Australopithecus skeleton with skull demonstrates for the first time that very early human ancestors were a unique form of ancient primate, rather than being apes with some human-like features: they stood upright, walked on two legs, had a short, broad pelvis, powerful, human-like hands that they used for grasping branches during climbing, arms and legs of similar length – but neither excessively long – and relatively small canine teeth. They also, however, retained some ape-like characteristics from their Miocene ape ancestors, including a flat nasal skeleton, slightly projecting jaws, a relatively small brain, and a foot with a slightly divergent big toe. These generalized ape characters do not suggest a relationship closer to chimpanzees or gorillas than to orang utans and gibbons. On the contrary, the fact that both chimp and gorilla have long arms and hands, used specifically for hanging from branches and for knuckle-walking on the ground, suggests that early hominids were not closely related to them at all. Instead, these hominids kept an ancestral form of unspecialized short arm, with a short, powerful hand and fingers and long, powerful thumb, useful for cautious branch climbing. By about 2.5 million years ago, this unspecialized human hand would provide some of the hominids with added advantages when they began to use it for making and using tools. Such simple beginnings led to the eventual development not only of complex culture, but also of the expansion of the brain.

Classifying our ancestors Perhaps we should follow the suggestion of Louis Leakey, in The Progress and Evolution of

Man in Africa (1961), to stop using the terms ‘ape-man’ and ‘man-ape’ for the australopithecines, as he said these terms suggest a much closer relationship to the apes than the facts warrant. Leakey preferred the term ‘near man’ for the australopithecines and ‘man’ for those that “made tools to a set and regular pattern.” Nowadays, it seems appropriate to use the genus name Homo for the toolmaker, and place Homo and the apparently non-toolmaking Australopithecus, Paranthropus, and their predecessors into the zoological family Hominidae (meaning ‘man’). They form a group of unique primates with their combination of powerful, short-fingered, long-thumbed hand, low and wide pelvis, upright posture, and small canine teeth. Given the implications of the Sterkfontein skeleton, I cannot agree with those who place certain Miocene apes (dryopithecines and Sivapithecus) plus the orang utans, gorillas, and chimpanzees all together into the family Hominidae, or those who place gorillas and chimpanzees together with humans and australopithecines into the subfamily Homininae, simply because of their supposedly close (but questionable) genetic relationship. Certainly our Sterkfontein skeleton demonstrates that, in the structure of the hand and arms, there seems to be no basis for relating chimpanzees closely to humans or to australopithecines. Our classifications need to recognize the fact that humans and australopithecines are unique, and different from all the apes. ■ Professor Ron Clarke is at the Sterkfontein Research Unit, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, Johannesburg.

Top: The complete hand and forearm of the skeleton. This is the first time that a hand and arm of the same individual australopithecine has ever been found. Scavengers would normally have destroyed these smaller bones, but this individual had fallen into a shaft, so it could not be approached. The find enables us, for the first time ever, to see the proportions of hand to arm measurements of an australopithecine. Compared to that of an ape, the strong, muscular arm is relatively short. Above: The left hand of the skeleton and the only complete hand of an australopithecine ever discovered. Its form is similar to that of a human hand but more muscular. The fist is clenched, with thumb bone and fingers folded into the centre of the palm (the knuckles are on the left of the picture).

For details about the skeleton, see R.J. Clarke’s “First ever discovery of a well-preserved skull and associated skeleton of Australopithecus”, South African Journal of Science, vol. 94 (1998), pp. 460–463, and “Latest information on the Sterkfontein Australopithecus skeleton”, South African Journal of Science, vol. 98 (2002), pp. 523–526. For dating details, see the paper by T.C. Partridge, D.E. Granger, M.W. Caffee, and R.J. Clarke, “Lower Pliocene hominid remains from Sterkfontein”, Science, vol. 300 (2003), pp. 607–612.

Quest 1(1) 2 0 0 4 27

John Cooper outlines South Africa’s albatross research at the Prince Edward Islands and our contribution to a new international seabird conservation agreement.

larming decreases in albatross and petrel numbers have caused global concern. Now an international Agreement on the Conservation of Albatrosses and Petrels (ACAP) hopes to reduce the threat of extinction for 28 species of these seabirds. South Africa’s only overseas possessions, the two chilly sub-Antarctic Prince Edward Islands (Marion Island and Prince Edward Island in the southern Indian Ocean), yield valuable scientific information. As many as 15 of the 28 species of ACAP albatrosses and petrels visit the islands, a significant breeding site for nine of these species – most of them globally threatened. The area also hosts more than 40% of the world’s population of the charismatic wandering albatross.

Researching our albatrosses and petrels

Above: A wandering albatross guards its chick in the snow. At the Prince Edward Islands, snow tends not to lie on the ground for more than a few days at a time, even in winter. The chick’s thick coat of white down keeps it warm when temperatures drop to zero (and even lower when the wind chill factor is taken into account). Photograph: P.G. Ryan Right: A shy albatross falls victim to a Southern Ocean longliner. The corpse will be studied to see if it originates from the Australian or New Zealand breeding populations. Such analyses identify the island populations that are most at risk and, therefore, where conservation efforts need to be concentrated. Photograph: P.G. Ryan

28 Quest 1(1) 2 0 0 4

Five years after South Africa annexed its islands, the study of albatrosses began on Marion Island in 1952 with the pioneering work of meteorologist J.J. la Grange. He banded wandering albatrosses Diomedea exulans near the island’s weather station and followed their breeding activities over two seasons. He found that that a successful breeding cycle – from nest building and courtship to fledging of the chick – took longer than twelve months, so the birds could not return in time to breed the following year. Because the birds were faithful to their mates and returned to the same site to breed after two years, it was possible to study individually marked birds throughout their lives. Since then, many biologists and field assistants have studied the islands’ albatrosses and other seabirds, focusing on their breeding biology, foraging ecology, diet, physiology, and population dynamics. We’ve found, for example, that the albatrosses eat a mixture of dead and live squid, fish, and small crustaceans, for which they make

shallow dives or which they seize from the surface. They forage (mainly during the day but also at night) up to thousands of kilometres when they are not breeding. Deon Nel, now Marine Programme Coordinator of WWF-South Africa, has carried out the most significant recent research on albatrosses at Marion Island. Bird counts over the last three decades show ominous decreases in numbers of several species, including the wandering albatross. The main reason seems the Southern Ocean longline fishing method for tuna and toothfish. Birds are attracted to the bait on the longline hooks. When they try to snatch it they get caught, then are dragged beneath the sea surface and drowned. Effective solutions include bird-scaring streamers and the setting of lines at night, but these methods need to be used much more widely.

Signing up to conservation

▲ ▲

Decreasing populations have also been recorded at other nations’ sub-Antarctic islands, and concern over these findings have given rise to ACAP. Instigated by Australia, and so far ratified by Australia, Ecuador, New Zealand, South Africa, Spain, and the United Kingdom, the agreement came into force on 1 February 2004. South Africa plans to attend the first meeting of the member states later this year. The agreement sets up conservation measures for the countries involved. Apart from reducing seabird mortality from longline fishing, it provides for research and monitoring, eradicating introduced species such as rats and feral cats at breeding sites, reducing disturbance and habitat loss, and reducing marine pollution. South Africa’s latest research on ACAP species at the Prince Edward Islands includes tracking wandering and grey-headed Thalassarche chrysostoma albatrosses at sea with geo-location loggers in their ‘sabbatical’ year when these biennially-breeding species are away from the islands. Headed by Peter Ryan, and carried out by the Percy FitzPatrick Institute of African Ornithology at the University of Cape Town (UCT), this work will tell us where these birds have travelled and spent their time at sea and will help ornithologists and conservationists decide where best to propose marine protected areas in the Southern Ocean.

Top left: Dark-mantled sooty albatrosses breed on little-visited Inaccessible Island in the Tristan da Cunha group of islands (a UK Overseas Territory). The island is a strictly protected nature reserve, recently nominated by the UK as a Natural Site of International Importance to the World Heritage Convention. Such action helps to protect these magnificent birds on land, but not from fishing mortality as they wing their way across the Southern Ocean. Photograph: P.G. Ryan Top right: Breeding Atlantic yellow-nosed albatrosses on the UK’s Gough Island in the South Atlantic Ocean. This species has been classified by the World Conservation Union as ‘Endangered’, following alarming downward trends in its population. Many are killed on longlines in Brazilian waters, which makes this beautifu bird’s status an international issue. Photograph: P.G. Ryan Above: A wandering albatross rests on the sea surface. When there is little wind and swell, albatrosses often rest on the sea, because flying in these conditions means they would need to flap, rather than glide and soar seemingly effortlessly against the swell. The Southern Ocean is normally windy and rough, however, so albatrosses are mostly seen on the wing when they are away from their island homes. Photograph: John Graham, Zestfor Birds

The ice was here, the ice was there, The ice was all around: It cracked and growled, and roared and howled, Like noises in a swound. At length did cross an Albatross*, Thorough the fog it came; As if it had been a Christian soul, We hailed it in God’s name. * And lo! The Albatross proveth a bird of good omen .... from Samuel Taylor Coleridge’s epic poem, The Rime of the Ancient Mariner (1798)

Quest 1(1) 2 0 0 4 29

E-mail from Thailand The wandering albatross ■ is the world’s greatest ocean flyer – in 10 months, one banded bird flew about 15 000 km; another flew more than 5 600 km in 12 days – and spends some 90% of its life at sea ■ together with some other species of great albatrosses, has the widest wingspan of any bird alive – more than three metres wide ■ forages over 30 000–50 000 ha of sea to find food – it feeds on squid and fish, and also follows ships and eats galley wastes dumped in their wake ■ usually stays faithful to one mate and very often returns to breed at its own birthplace after its travels ■ builds a grass and mud nest half a metre off the ground. The female lays a single egg, which both parents take turns to incubate for 80 days. The chick takes a year before leaving the nest to go to sea. It takes 10 years before starting to breed. It can live as long as 50 years. ▲

New research, led by Marienne de Villiers of UCT’s Avian Demography Unit, has begun at Marion Island this year to study the effects of human disturbance on some of the ACAP species. Preliminary findings suggest that people should keep at least 15 metres away from breeding wandering albatrosses to avoid causing them undue stress. Such information is crucial when planning for tourism on islands where albatrosses breed. To conserve seabirds threatened by longline fishing, a draft South African National Plan of Action for Reducing the Incidental Catch of Seabirds in Longline Fisheries has been drafted under contract by John Cooper and Peter Ryan, following 1999 guidelines produced by the Committee on Fisheries of the Food and Agriculture Organization of the United Nations (FAO). Once formally adopted, this plan will also apply to the waters surrounding the Prince Edward Islands, and will in this way support the aims of the Albatross and Petrel Agreement. We expect conservation research on albatrosses to continue at the Prince Edward Islands, so that South Africa may continue to keep the wanderer and its relatives flying the Southern Ocean. ■ Dr John Cooper is Chief Research Officer at the University of Cape Town’s Avian Demography Unit.

South African scientists work in all kinds of places. Eminent ornithologists Alan and Meg Kemp are researching little-known animals and plants in the Malesian rainforests. Here’s how they’re doing it. From: Alan and Meg Kemp <leadbeateri@hotmail.com> To: editor.quest@iafrica.com Sent: Tuesday, April 06, 2004 6:28 AM Subject: E-mails from South African scientists abroad Hallo, QUEST readers! We’re working for a year at the Hala-bala Wildlife Research Station, in south Thailand on the border with Malaysia. We’re in touch, sort of, and not too in the boondocks. Our local e-mail is at the village of Ban Bo Ke Ta, about 8 km away, available on most days if we need it (now we’ve purchased a 10-year-old Suzuki jeep), except for Friday (mosque day) and Saturday (the 2nd day of the weekend). But it’s housed in a little wooden shack in a field and runs via a local landline, so it’s not fast and not 100% reliable. An hour’s journey (36 km) takes us to Sungai Kolok where there’s a faster Internet café (subject only to Chinese holidays, so far). In an emergency, try our Thai cellphones, though we only have a signal at the Park boundary 2 km away. Over the past decade we have attended hornbill conferences in Thailand and done short periods of fieldwork, each time with colleagues at Mahidol University, Bangkok. Now we’ve been invited by BIOTEC, the National Centre for Genetic Engineering and Biotechnology, to assist with studies of little-known animals and plants in the Malesian rainforests. We’re studying hornbills (visit www.nfi.org.za), diurnal birds of prey, and owls, and other species where possible. No biologist can fail to be impressed by rainforest. We live in a little two-roomed cottage on the edge of the forest, with seven species of large Asian hornbills audible, and sometimes visible, all round us, and seven genera of raptors recorded already, from tiny falconets to the odd Asian black eagle. But it’s notoriously difficult to make observations in rainforest (annual rainfall: 5 m), especially with our background of a dry, two-dimensional, South African savanna habitat. We arrived at the end of the main south-east monsoon, so there’s been plenty of rain and plenty of leeches to keep us alert as we walk in the forest. We have excellent local guides and, apart from some communication problems with their English and our even more negligible Thai, we’re finding our way about without any serious mishaps. There is a system of short trails immediately around our camp – one leading under the local nest of a bat hawk. One of our goals is to collect data that will improve first estimates of density for some 10 bird species counted previously. We’ve now chosen a series of six lookouts from the tar road and, as often as possible, will record, within each hour, the number of focal species we see or hear. Our coverage at each site is confined to the area of a large valley and the slopes of the opposite hills, so that for large, noisy and/or aerial species of hornbill and raptor we intend to build up a picture of the species and numbers potentially visible from each site, and to compare this to what we record during our 1-hour watches at different seasons and times of day. Once the monsoon ends and the dry season (a relative term) starts, most birds start nesting, and we’ll make detailed observations on selected species. This includes searching a four-hectare plot deep within the forest, conveniently divided into a 20x20 m grid system to record all birds we see or nests that we can discover. So far we’ve only seen signs of deer, tapir and small carnivores – nothing yet of tiger or black panther. But we’ll send more details in a couple of months’ time! Best wishes

For ACAP see J. Cooper and P. Ryan, “The Agreement on the Conservation of Albatrosses and Petrels”, South African Journal of Science, vol. 97 (2001), pp. 78–79, and visit

Alan and Meg c/o Halabala Wildlife Research Station, PO Box 3, Waeng Naratiwat, 91960, Thailand

www.ea.gov.au/coasts/species/seabirds/albatross

For SA research on ACAP birds, visit www. aviandemographyunit.org.za

Read R.J.M. Crawford and J. Cooper, “Conserving surfacenesting seabirds at the Prince Edward Islands”, African Journal of Marine Science, vol. 25 (2003), pp. 415–426, and D.C. Nel et al., “Population trends of albatrosses and petrels at sub-Antarctic Marion Island”, Polar Biology, vol. 25 (2002), pp. 81–89. For more on the region, consult J. Rubin, Antarctica (Hawthorn, Victoria: Lonely Planet, 2000). Photograph: Courtesy of the Hornbill Project Thailand

30 Quest 1(1) 2 0 0 4

Is virtual learning in higher education the way to bridge that digital divide everyone’s talking about? We report on Martin Hall’s view that it could be if it’s done the right way – but there’s no quick fix solution. he increasing gap between rich and poor people and nations needs urgently to be bridged. One way is to understand the new digital opportunities on offer for education, and to design the means for using them to best advantage in the developing world. At the University of Cape Town, deputy vicechancellor Martin Hall has been examining the contexts and possibilities of virtual learning – and the concerns. The world’s economy, he argues, is increasingly dominated by the digital and educational divide. We need to bridge it. The question is how? We are still feeling our way in trying to discover how well and in what conditions people can master this technology. Perhaps the answer lies in our access to it and in the type of courseware we use.

The great divides

Is virtual higher education the answer? For many, the flexibility of the Internet is the key to the future of higher education and offers a vision of affordable, accessible ‘borderless’ learning. Others argue that profit for the suppliers of network hardware, software, and ‘content’ is the underlying motive for the rush towards elearning, that the quality of education will drop as teachers lose face-to-face contact with their students, and that conditioning by multinationals who control the programs will replace the activities of independent learning. Setting up e-learning facilities can, furthermore, be an investment so great that it needs large-scale transnational partnerships to make them possible. E-learning at the Harvard Business School, for instance, introduced in 1995/96, was within three years providing on-line learning for 1 600 full-time MBA students, 5 000 executive education students, and 66 000 alumni – at a start-up cost of US$8 million and a further maintenance cost of US$8 million a year. Whatever the objections, however, the Internet is in practice the world’s most widely used tool of interactive communication and information sharing. It is integral to education and the essential fibre of the network economy. In developed

Some definitions The network economy broadly describes high-tech and low-tech developments in the globalised 21st century at work. A skilled ‘information elite’ has emerged, skilled in ‘surfing’ the rapid changes in the new technology, whose dealings depend on applying it – for example, across the financial centres of London, New York, Tokyo, Johannesburg, and elsewhere. At a lowertech level, cheaper globalised support services are on offer, such as the huge call centres in India that service the telephone needs of first world countries on other continents. The knowledge economy is at the heart of the network economy; the phrase refers to the increasing world trade in knowledge, information, and expertise, as distinct from trade in manufactured products and commodities such as raw materials and food.

▲ ▲

The Internet makes large quantities of information instantly available at the touch of a keyboard button, as well as new forms of communication across great distances (by means of e-mail, on-line discussion, chat rooms, multi-user dimensions, and real-time video). Access to the global information pool, combined with the right know-how, opens the door to great economic and social advantages to individuals and nations. Part of the reason is that developed economies have started accumulating wealth more and more through the flow of investments and less through the production of tangible goods and services, which, in turn, has increased the economic divide between have’s and have not’s. In his studies of the information age and global capitalism, Brazilian sociologist Manuel Castells argues that the ‘new’ economy has built up the demand for an elite workforce of individuals, able to offer the updated expertise and networking skills on which this economy depends. Those excluded from the information elite are seen as ‘generic labour’, disposable, devalued, and increasingly irrelevant. They are assigned support work of one kind or other that neither empowers them nor leads to their further development. Education is the critical factor determining who can join the information elite and who is restricted to the pool of generic labour. More specifically,

the digital divide is reflected in the economic divide, for both distinguish between those with access to and mastery of the new technologies and those without. In Africa, the spread of the Internet mimics earlier patterns of colonialism and discrimination, since information networks act as gatekeepers to the new economy. Within these networks, argues Castells, new possibilities for economic growth abound; outside them, where information sources are unaffordable or unavailable, survival for nations as well as individuals is increasingly difficult. Charles Leadbeater, in Living on Thin Air: The new economy (2002), sums up the situation: “While a global super-class grows fat on markets in which the winners take the lion’s share of the rewards, many others find their life chances closed down. Inequality has become ... acute, chronic and endemic”.

Quest 1(1) 2 0 0 4 31

▲

societies the new technology has blurred the distinctions between ‘contact’ and ‘distance’ educational institutions. And it is changing the geography of economic and social privilege, making the ‘information elites’ of New York and Gauteng more similar to one another than to the ‘information ghettos’ of Harlem and Hillbrow. For South Africa to benefit from the world’s growing network economy, rather than losing ground, we need to embrace information and communication technologies and to find ways to widen access to them through our higher education institutions.

New learning for the developing world Higher education that is accessible and that meets acceptable standards is now recognized as essential to the future of developing countries. This reverses earlier assumptions that basic literacy was more important than high quality tertiary provision. Population growths throughout the world lead to rising demands for access to university education, which in many countries is still restricted by the limited resources of conventional ‘bricks and mortar’ institutions. To overcome such problems, the World Bank’s Task Force on Higher Education and Society, in Higher Education in Developing Countries: Peril and promise (2000), calls for research into providing for the future by combining “innovative

Digital learning by doing How can developing communities at the margins of the new economy use the emerging technologies not just to absorb information but to learn how to learn and to question? By applying the content of available programs to everyday reality. Experience comes first, followed by observation, judgement, discussion, and action.

Experiencing the world of finance In a New York example designed by Classroom Inc., students learn about financial processes through a ‘virtual bank’ case study in which a woman requests a loan, has her credit status assessed, and opens an account. Student groups of three around a single computer take on different roles as they work through the case study material, debating and arguing their decisions as they apply and adapt new-found knowledge to real-world experience. The non-profit organization, Classroom Inc., develops simulations of everyday situations. Visit www.classroominc.org

What’s scary about digital communication? In another example, a simulation combines e-mail, word processing, and Web pages, to encourage students to communicate electronically. They publish their own home pages and take part in e-mail discussions, which opens up new possibilities for dealing with others. Students find themselves fearlessly exploring different registers, taking part in several different conversations at the same time, and experimenting with differing roles and identities. For more, read Marion Walton and Stella Clark’s Extending Interactivity: Academic literacy in an online writing environment (Cape Town: University of Cape Town, 1998) and visit www.meg.uct.ac.za

Questioning the hamburger Everyday experience is a starting point for simulations, following pre-digital examples such as that of Ira Shor, teaching at the City University of New York at the time of open admissions in the 1970s. “I bought a hamburger and took it to class. What better way to extraordinarily reexperience the ordinary? The burger is the nexus of some many daily realities. It is not only the king of fast foods ... but it’s also the source of wages for many students who work in the burger chains. In addition, the spread of fast food franchises is tied into the suburban dispersal of the American city. ... to the automobilization of American life. ... My students have eaten, cooked and sold countless numbers of hamburgers, but they have never reflected on all this activity. I brought a burger to class and interfered with a major uncritical flow of mass culture. It was a lucky break....” Online learning that interrogates the ordinary in this way can be low tech and specific to different cultural environments. And it can build successfully on peer interaction, avoiding the high development costs of first world e-university programs. For more, read Ira Shor’s Critical Teaching and Everyday Life (Chicago: University of Chicago Press, 1987).

32 Quest 1(1) 2 0 0 4

curricula ... with interactive, Internet-based technology, traditional educational media such as television and print, written materials and direct contact with tutors”. What exactly happens to the process of learning, however, when we replace personal face-to-face education with the virtual kind? The problem is that we don’t really know, even though huge sums have been spent on developing digital resources for the new knowledge economy. There is so far no conclusive evidence that digital learning on its own yields better results than face-to-face personal interactions. It is possible that those who have already learnt how to study successfully and know what methods to use to conduct research are most likely to benefit from the new media, whereas those who lack such skills could still be left behind. While appearing to offer digital access to all, Internetbased education, if implemented indiscriminately, could merely reinforce existing disparities. What’s needed is to apply digital learning rigorously to the practical experiences of those who learn, and encourage them to organize those experiences and to understand them in the context of real life. Effective learning in the virtual classroom, moreover – as distinct from the efficient transmission of information – depends on small tutorial group size (no more than between 12 and 20, studies suggest), to allow participants to ‘chat’ to their tutor and to one another as individuals. There is, nevertheless, space for massdelivered courses that emphasize content and retention over individualised thought, for those already able and motivated to research alone. Effective virtual learning, then, lies not in the fact itself of being connected, but in the quality of interaction between learners and teachers. It lies, too, in the design of appropriate courseware with: a high degree of local orientation; support for the experiential learning that is crucial for genuine educational advances; and imaginative forms of peer support. Finally, in a developing country like South Africa, there is a need to counteract the tendency by large corporations to tie educational institutions into ‘bundled’ interlinked systems. One way is to develop an accessible body of local open system courses that are developed collaboratively, in the national interest, by our own public higher education institutions. However we set about it, we need policy and practice to avoid the global trend that differentiates between the developed world and its peripheries. The most appropriate response, concludes Hall, is to prevent profiteering and promote fair use through strong local innovation that is strengthened by collaborative centres of excellence. ■ The source for this report is an unpublished paper by Martin Hall on Digital Learning and a subsequent interview. For current developments, visit www.meg.uct.ac.za Professor Martin Hall is Deputy Vice-Chancellor at the University of Cape Town and his responsibilities include institutional planning and budgeting, communication and development, and issues to do with higher education.

Q The S&T tourist

Elephant rock No matter if you’re at home or visiting from afar, there’s always plenty to see if you know what to look for. Geographer and tour guide George Roberts takes a look at ‘elephant rock’ dolomite in South Africa’s northern provinces. A blind S&T tourist from Soshanguve feeling the ‘elephant-skin’ surface of the dolomite. Photograph: Courtesy of George Roberts

riving around South Africa’s North West, Mpumalanga, Limpopo, and Gauteng provinces you can see exposed dolomitic rock. It’s called Olifantklip (‘elephant rock’) in Afrikaans, because, above ground, it looks like sculpted elephant skin – rough, with knife sharp edges along many of its ‘folds’. Like its namesake, the rock blends shades from brownish black through varieties of blue-grey to white. It appears in many types of surface outcrop, from mountain ranges to rock pavements and karst pinnacles. Sometimes it’s covered with very ancient dome shapes called stromatolites. At other times, layered with thin off-white or ivory coloured insoluble chert, it forms mini-cliffs or ‘bread-and-butter’ formations. These wonderful and varied shapes occur because rainwater erodes these watersoluble carbonate rocks in exotic ways. Underground, their capacity to dissolve has created many other sculpted features, including buried rivers, sinkholes, and caves. The famous ones in the area of the Cradle of Humankind in Gauteng are renowned for their fossil remains of extinct mammals and our early ancestors. It is, in fact, dolomitic outcrops that palaeontologists seek out in particular. That’s because rainwater in these caves dissolves the carbonate,

creating voids and chasms which fill with debris, and redepositing carbonate as solid rock to form beautiful stalagmites and stalactites. When bodies die and fall into the caverns they become entombed as the deposited carbonate encrusts and mummifies them, and their bones are preserved there as fossils. This part of the country is dolomitic because, some 2 500 million years ago, its precursor, limestone, formed there, in a vast, shallow inland sea. Primitive organisms formed stromatolite colonies and flourished, together with minute creatures like algae. When they died their structures sank and accumulated beneath the water. All these carbonate sediments formed layers hundreds of metres thick above the sea-floor, and were later covered by thick deposits of silt and sand. Over a period of hundreds of millions of years, these deposits hardened into massive, thick, rock layers. The carbonates became limestone, which, in time, and in the presence of seawater, gradually consolidated. The pressure of deep burial and violent upheavals such as earthquakes and volcanoes (where the surface of the earth is disturbed, distorted, and fractured) caused it to metamorphose into dolomite. Crustal forces and erosion have exposed the dolomite. It forms a belt around Johannesburg, with an arm

reaching Pretoria, widening westwards to the Botswana border. As a long, untidy ribbon, it also occurs in the rugged highlands to form the Mpumalanga Drakensberg, then stretches westwards into the Strydpoortberge, varying from about one to 15 kilometres in width. ■ For details read M.J. Viljoen and W.U. Reimold, An Introduction to South Africa’s Geological and Mining Heritage (Randburg: Mintek, 1999). Limestone (or calcium carbonate, CaCO3): composed of the shell remains of dead marine animals, it is a raw material in the Solvay process for the manufacture of soda (sodium carbonate), Na2CO3. It is also used in making cement, glass, quicklime (calcium oxide), and slaked lime (calcium hydroxide). Dolomite: a sedimentary rock consisting of calcium magnesium carbonate, CaMg(CO3)2. It is an important source of magnesium and is also used as a building stone and as a refractory material (i.e. its high melting-point means that it is able to withstand high temperatures and can, for instance, be used to line furnaces). To see dolomitic rock formations visit: ■

the highways and main roads of North West, Mpumalanga, Limpopo, and Gauteng provinces

■

the two other areas in South Africa where carbonate rocks occur: the ancient (Proterozoic) Ghaap plateau of the Northern Cape province and the geologically more recent (Tertiary) patches of limestone along the coast of the Western and Eastern Cape provinces, as well as along the Elephant coast of KwaZulu-Natal

■

the Cradle of Humankind World Heritage Site (the rock stretching northwards from the Sterkfontein Caves)

■

rockeries in private homes and public parks.

Quest 1(1) 2 0 0 4 33

The South African Journal of Science, our flagship multi-disciplinary scientific research journal, turns 100 this year. How has it progressed and what does it contribute to the country’s science profile?

1904 hat 20 years later became the South African Journal of Science (SAJS) first appeared in 1904 as the Report of the South African Association for the Advancement of Science (S2A3), a collection of papers presented at the association’s first meeting held the previous year. Today, published bimonthly, the journal ranks in the second quartile of the world’s multidisciplinary science journals listed in Philadelphia’s Institute for Scientific Information (ISI), the only one in Africa, and ranking 15th out of the 48 appearing in that index. Says Graham Baker, its editor for the past 30 years, “To see what science was being done in South Africa at any time in the last century, turn to the SAJS of that period for the flavour of what was being reported and in what way.” According to Wieland Gevers, president of the Academy of Science of South Africa (which has published the journal since 2002), Baker “has provided a Nature for our time and place.” The journal celebrated its centenary by going fully electronic, and its papers are now available on the Web as well as in print.

Discovery and measurement A 1904 overview by S2A3 president, Sir Charles Metcalfe, portrayed a time of discovery, measurement (of places and people), and making sense of a world very different from ‘home’ (Britain): During the past year progress has been made with the magnetic survey of South Africa....The work at each station [362 stations in the Cape Colony, Transvaal, Orange River Colony, Natal, and Rhodesia] consisted in determining the latitude and the longitude of the place of observation, the magnetic declination, the horizontal intensity, and the dip.

34 Quest 1(1) 2 0 0 4

The total money granted for this survey was £2 465 10s. Elsewhere, a geological survey of the Cape Colony examined a “peculiar group of volcanic necks in Sutherland”, while marine investigations by the Cape Government uncovered “many new and interesting specimens of marine life.” The visionary intention of a further survey, the Geodetic Survey of Africa, was to: ... extend it northwards, more or less, probably along the route of the Cape to Cairo Railway [which] to many appears, perhaps, to belong to the things of dreamland. ... When this Geodetic Survey has been connected with that of Europe, which has now been extended as far north as Spitzbergen, we shall have an arc from that point to Cape Town – the longest arc that is possible to us on this globe.

Global contexts Noteworthy were discoveries abroad from research on radium, ... carried out by many of the greatest scientists of the day, especially by Professor Rutherford, Sir William Ramsay, Mr. Soddy, Professor Becquerel, Sir William Crookes, Professor Dewar, and last, but not least, by M. and Mme. Curie.... Some idea of the laborious and patient investigations which M. and Mme. Curie have carried out may be gathered from the fact that after two years of continuous work they have succeeded in obtaining about one gramme of Radium chloride after treating some eight tons of uranium residues. This gives us a good illustration of a great saying that “science is slow.”

Also overseas, records were broken “in high speed electric traction on the Marienfelde-Zossen [railway] line in Germany, where a maximum speed of 130 miles [209 km] an hour was attained with safety.”

Scientists everywhere looked into the minute, making progress in “our knowledge of the internal structure of metals by the aid of microscopical research”, as distinct from the ‘old’ methods of analysis and mechanical tests. They also looked outwards, exploring the Arctic, the Antarctic, and the interior of Africa: “Mr Chevalier has discovered where the basins of the Nile, the Congo, and the Shari Rivers meet”. Tropical diseases were fruitful areas of research in Africa. Scientists in Uganda discovered that sleeping sickness was caused by a parasite carried by a species of tsetse fly. African Coast Fever among cattle in what was then Rhodesia was found to be spread by ticks, and it was recommended that animals should be inoculated “with the blood of animals that have recovered”. South Africa was, moreover, offering the rest of the world the benefits of its scientific research: When England was ravaged by Rinderpest, no remedy was discovered: the animals affected were simply destroyed, at a cost of some nine millions of money. It was left for South Africa, at a later date... to be the first to discover a preventative for that disease, a fact of which this country may be well proud.

Reef of gold Many papers in the 1904 Report discussed gold mining on the Witwatersrand. Scientists worked on the cyanide process of extracting gold, and were checking the gold reduction works to determine the skill and honesty with which the metal was extracted. Prospecting by drilling was a necessary economic evil, wrote G.A. Denny:

SAJS changes over the years.

Machine drills for prospecting purposes have become a recognised media for the prosecution of research in the hidden depths of the earth, whether the object of that research be purely scientific, as in the Nile borings, or whether for the more sordid purpose of locating metalliferous and other deposits of economic value as in the gold and other prospecting borings in the Transvaal.

Comparisons between the pail system for collecting foul matter and water as now practised in this Colony and the waterborne and bacterial purification show that for every £3 now spent on rates by householders for the pail system, £1 would be saved by substituting the modern water method. Apart from the saving in expense, the benefit to health would be most incalculable.

A further paper by J.C.S. Beynon explained the ‘Septic Tank System’ as “the most successful method of bacteriological treatment.”

African extremes Aspects of South Africa seemed strange and frightening to the foreigners. Even bacteria in the Transvaal were more virulent than their counterparts in Europe and Britain. F.H. Joseph, assistant bacteriologist at the Government Laboratories, enumerated “striking points of difference”. The pneumococcus of the Transvaal was “at least ten times as virulent as the home types”; meningococcus grew at lower temperatures and more quickly; Bacillus pyocyaneus, which gives “the peculiar tint to green pus” and had been found in Transvaal water supplies, while rarely so in Britain; Bacillus pestis, the prime cause of bubonic, septicaemic, and pneumonic plague (which latter was ravaging Johannesburg at the time) could kill people within 24 to 48 hours. Miners’

phthisis killed Rand miners at a younger age than it killed those in Europe. Then as now, scientists tried to harness nature’s resources. While recognizing that “there is no royal road to irrigation”, W.R. Bell was determined to wrest “the treasures of life bit by bit from the unwilling earth” by building water reservoirs. Although meteorological records in Johannesburg went back only 15 years, he already wondered “whether the droughts of recent years point to a change of climate”. C.M. Stewart, of the Meteorological Commission of Cape Colony, reported on the 1902 blizzard. Started at about 6 p.m. on 9 June, it had continued, “practically without intermission” until the morning of the 12th. Snow, sleet, and rain covered nearly all South Africa. Temperatures in Windhoek fell to -9ºC, Table Mountain was covered in snow, and snowdrifts were 6 metres deep in places. Mapping and naming were ways to control nature. Andrew F. Crosse was determined to “attain victory” in the “longer, sterner war, the fight with Nature” by deducing the nature of the Transvaal’s soils formed from the disintegration of rocks. In this way, science would allow “us to cultivate land barren to previous generations” and to “build a nation here” in which “the agriculturist will be, must be, the backbone”. Joseph Burtt Davy started mapping 141 species and varieties of ‘spontaneous alien plants’ (which grew without being artificially planted or cultivated) in the Transvaal to determine which had become “troublesome” weeds to be eradicated. Xanthium spinosum (burrweed), for example, had prickles that

▲ ▲

Even the science of forestry was geared to the gold mining industry. Mining companies’ attempts to establish eucalyptus plantations were “of very little avail, owing to the unfortunate circumstance of having planted the wrong varieties”, reported D. Gough Muldoon, who recommended instead Australian hardwoods, such as teak and beech. Less useful trees for mining, in his opinion, included trees with the evocative names of Snap Short, Maiden’s Blush, Lilly Pilly, and Tameron Toothache Tree. William Cullen pointed out the country’s dependence on resources: “The Gold Mining Industry of the Transvaal is such a large factor in the country’s prosperity, that we occasionally forget the possibility of others”. He recommended developing the chemical industry and of manufacturing, amongst others, “artificial manures”, candles from shale, chloride of lime for “sanitary matters”, and, as mielies and potatoes became cheaper, he suggested distilling, for “Plenty of good whiskey is made from potatoes and maize – prejudices against them not withstanding.” In the pioneering town of Johannesburg, Stephen Court was finding ways to meet the cost of “constructing the many miles of roads requiring to be made in Johannesburg, and of laying sewers and storm water drains”. E.W. Sloper

pleaded for architects to take into account “considerations imposed by country, climate, and the character of surroundings” when designing houses. (Herbert Baker, as was his custom in the northern hemisphere, incorrectly faced his buildings south in South Africa.) In the matter of sewage disposal, Ernest S. Prentice reported “immense advances”:

Quest 1(1) 2 0 0 4 35

News Q

Palaeontologists Neil Shubin and Michael Coates from the University of Chicago and Ted Daeschler from the Academy of Natural Sciences in Philadelphia have found the puzzle piece that could explain how landliving animals evolved from fish. The news (published in Science on 1 April 2004) is that their remarkable fossil, a 365-millionyear-old ‘arm’ bone, has features both of primitive fish fins and of true limb bone, giving a glimpse of the evolution in structure and function and bridging the evolutionary

gap between fishes and amphibians. The structure of the bone shows evidence of powerful forelimbs, with large areas on the shoulder for attaching the muscles that would have been used to prop the body up and push it off the ground. Although the fossil was found in 1993 in Pennsylvania, it was only recently that its significance became apparent, with the removal of the red sandstone in which it had been encased. For more information visit www.nsf.gov/home/news.html#story1

Jewellery – the oldest ever found People have been adorning themselves for at least 75 000 years. So believe the archaeologists who discovered Nassarius shell beads at Blombos Cave, 300 km west of Cape Town. Ornaments previously found were ‘only’ 45 000 years old. The 41 mollusc shells, found in clusters of up to 17 beads, have had holes bored in them, and show signs of rubbing from the material on which they were threaded. Using shaped tools and symbols has been thought of as a relatively ‘modern’ development (40 000 to 50 000 years ago), when our ancestors spread from Africa to Eurasia. Christopher Henshilwood, programme director of the Blombos Cave Project and professor at the Centre for Development Studies of the University of Bergen in Norway, and his colleagues believe that their discoveries at Blombos

show that social behaviours were already developing gradually during the Middle Stone Age. For details visit www.nsf.gov/od/lpa/newsroom/pr.cfm?ni=75

These marine shells were selected for size and perforated 75 000 years ago. Photograph: C. Henshilwood & F. d'Errico

Tracking fishes in the Eastern Cape The Great Fish River estuary is a favourite fishing spot for visitors and for local communities who fish for their food, and stocks of spotted grunter and dusky cob are being depleted. To manage and sustain the estuary’s fish resources we need to know more about the behaviour of the targeted fish – their population, their habitats, and their migratory behaviour. Juvenile spotted grunter and dusky cob are spawned at sea, and spend their first few years growing up in the nutrient-rich estuary where the fishing occurs. A project initiated by Dr Paul Cowley, aquatic biologist at the South African Institute for Aquatic Biodiversity (SAIB), and Dr Tor Næsje of the Norwegian Institute for Nature Research (NINA) will find out how these species behave in the estuary, discover how much time they spend in the sea and in the estuary, and study their movement between the two habitats. Telemetry, or electronic tagging, is used to track individual fishes in the Great Fish estuary. Acoustic transmitters (fish tags)

36 Quest 1(1) 2 0 0 4

transmit coded signals on a fixed frequency, so several individuals can be followed simultaneously. The transmitted signals are retrieved in two ways: first, by stationary receivers positioned in the estuary, and, second, by a hand-held receiver or hydrophone used from a moving boat. The stationary receivers monitor the presence or absence of individual fish within a fixed reception range, while the hydrophone monitors individuals more intensively and obtains high-resolution data. The project team will collate fishery statistics and catch data with the calculated movement trends, to assess how vulnerable the species are to localized depletion. They are also exploring the effectiveness of area closure (of estuarine protected areas) as a possible conservation strategy for the juvenile fish. Their work will contribute nationally to the development of sustainable exploitation strategies for managing subsistence and recreational fishing. – Margot Collet (SAIAB)

▲

Ancient fish ancestor of land animals

... become tangled in the wool of sheep, the hair of goats, and the tails and manes of horses, mules and donkeys. They not only cause irritation and annoyance to the animals, which seriously checks their growth, but greatly diminish the commercial value of the wool and mohair

and they damaged wool-cleaning machines. There were already laws against it in the Transvaal and three colonies. A friendlier alien was the Gynandropsis pentaphylla, whose “seed-pod, placed in the ear, will quickly extract any accumulation of wax”.

Social sciences People and cultures ‘alien’ to the Europeans were also of great interest. J.P Johnson recorded for the first time tiny Eolithic and Palaeolithic stone implementson the farm Elandsfontein: “The delicacy of workmanship displayed by these examples is all the more remarkable, when it is remembered that a large proportion of them are made from such refractory materials as greenstone and quartz”. Psychology also featured, with P.A. Barnett’s new approach in “The Handling of Young Children”, where Rule 1 was to respect each child’s individuality: “Do not force on every child the same discipline.” For example, “Jacobus likes his fat legs apart, while Jacoba loses nothing in mental concentration by being made to keep her heels together.” Children should be taught “how to amuse themselves” and be allowed to chatter, for there is “no unholier sight in earth, heaven, or education than a large class of little children kept quiet as stones for more than five minutes.” Above all, “the teacher of little children must be circumspect, judicial, urbane, firm, merciful.”

Looking forward The SAJS role, writes Gevers, is to be “an internationally recognized, highreadership, high-impact, multidisciplinary journal reflecting and projecting South Africa’s scientific capacity and special contributions”. Baker agrees: “Doing research is a privilege, normally paid for by the taxpayers, so they’re entitled to know what they’re getting in return. It’s a combined duty of the journal and South Africa’s researchers to showcase their scientific results and report their news in a way that lets the country know it is being well served.” ■ Visit www.sajs.co.za or e-mail: sajs@nrf.ac.za

Dr Graham Baker has been editor of the SAJS since January 1973.

Q News

MEASURING UP Computer science crumb – a unit of information; equal to 2 bits; 2 crumbs equal a nibble. flops – a unit of computing power; equal to one floating point operation per second. (A floating point number does not have a fixed number of decimal places and is stored with as many digits as the computer will allow; a floating point operation is an addition or subtraction of 2 floating point numbers.) Teraflops, trillions (1012) of floating point operations per second, measure the power of supercomputers. jiffy – the length of one cycle, or tick, of a computer’s system clock; equal to about 10 milliseconds (0.01 second). mickey – a unit used to program input devices such as mice; equal to the length of the smallest detectable movement of the mouse, about 0.1 millimetre; named after Mickey Mouse. nibble – a unit of information; equal to 4 bits or 1/2 of a byte. twip – a unit of distance used in computer graphics; equal to about 17.639 micrometres; an acronym of ‘twentieth of a point’. word – a unit of information; the amount of data processed by a computer in a single instruction; in personal computers it is equal to 16 bits or 2 bytes, and in large mainframe computers it can be as large as 64 bits or 8 bytes. A shortword is 2 bytes; a longword is 4 bytes; and a quadword is 8 bytes.

Extremes aeon/eon – in astronomy and geology, a thousand million years. billion – in the US, and as widely used (bn or B) elsewhere, this term means 1 000 million (109); in the UK, 109 is called a milliard, and the term billion refers to a million millions (1012). shed – in particle physics, used to express the apparent cross-sectional area of a particle from which other particles are scattered; equal to 10-24 barn (10-28 m2), or 10-52 m2. yottametre – a metric unit of distance; (Ym)

equal to 1024 metres, 32.408 megaparsecs (Mpc), or 105.7 million light years. (The radius of the observable universe is about 200 yottametres.)

High-level support for nuclear fusion Unlike nuclear fission (which creates dangerous, long-lived radioactive decay products) and fossil fuels (which release the greenhouse gas carbon dioxide and other atmospheric and solid pollutants), nuclear fusion promises genuinely ‘clean’ energy in abundance. Physicists have tried to master nuclear fusion ever since they realized that this is the mechanism that powers the Sun and other stars. It involves heating a mixture of the smallest atomic nuclei, usually hydrogen isotopes such as deuterium and tritium, to very high temperatures so that the nuclei combine, thereby producing helium and releasing huge amounts of energy that make the reaction self-sustaining. Unfortunately, it is very difficult to reproduce in the laboratory what goes on inside a star. For one thing, it takes a lot of energy to heat the reacting nuclei to a temperature of the order of 100 million degrees kelvin while confining them within a strong magnetic field. So, despite heavy investment in experimental reactors by several countries over past decades, the promise of this source of unpolluted power remains unrealized; indeed, there is scepticism that it will ever be fulfilled. But the prospects for fusion power now look brighter. The chief scientific adviser to

the UK government, Sir David King, who is a chemistry graduate from the University of the Witwatersrand and head of the Chemistry Department at Cambridge University, declares that he has “changed his mind” about the feasibility of controlled nuclear fusion and believes that an international consortium should build on past experience with test equipment and proceed with constructing the next generation of reactor. Writing in New Scientist (10 April, p. 20), King gives his reasons for supporting fusion research. These include the results of experiments in the UK and Japan that show it is now possible to reach the necessary temperatures and to sustain them in a fusion reactor while creating as much energy as was needed to achieve fusion initially. The next stage in the process is to build a bigger reactor (called the International Tokamak Experimental Reactor, ITER), possibly in France or Japan, to confirm the feasibility of fusion as the basis of a power plant. This will involve large-scale contributions from many countries. According to Professor King, “This fasttrack approach is capable of delivering fusion power within 30 years,” and its impact “will be bigger than landing the first man on the moon.”

Inkaba ye Africa for the country’s earth sciences In January, the governments of Germany and South Africa formally signed up to a US$14 million collaborative programme. It created a consortium of 15 institutions in the two countries to examine a segment of Earth (including South Africa and surrounding ocean) in the shape of a cone extending from the core out through the atmosphere into space. Interconnectedness is the key to the project, as suggested by the Xhosa word ‘Inkaba’, meaning ‘navel’. Bold research questions are being asked, and black graduate students are benefiting from the generous research capacity building aspect of the project. How did the components of this segment of Earth evolve during the 200 million years since the Gondwana supercontinent started breaking up? How did the changes within the Earth affect South Africa’s geographic features? The answers could help to explain many things, including shifts in the Earth’s magnetic field and the way in which

minerals are distributed. According to Maarten de Wit, UCT geologist and a driver of the project, the subcontinent has “the longest and bestpreserved geologic record in the world” because much of it comprises the Kaapvaal Craton, a section of Earth’s crust that has been stable for more than 3.5 billion years. Its hundreds of kimberlite (or magma) pipes – famed sources of diamonds – bring samples from the depths of the Earth close enough to the surface to examine. Blasting in the country’s deep mines creates earthquakes and excellent conditions for the study of fractures in rock and basic earthquake physics, and greater understanding will help to make our mines safer. A hole in Earth’s magnetic field drifting in the direction of the west coast of South Africa could play a part in determining whether or not the direction of Earth’s magnetic field is about to change over. For more details see Science, vol. 304 (2004), 380-381.

Quest 1(1) 2 0 0 4 37

On 15 March 2004, astronomers Mike Brown (California Institute of Technology), Chad Trujillo (Gemini Observatory), and David Rabinowitz (Yale University), announced their discovery of Sedna (2003 VB12), the coldest, most distant object known to orbit the Sun. How did they search and what did they find? Artist’s impression of Sedna: R. Hurt – SSC-Caltech, JPL-Caltech, NASA

inding Sedna: Since autumn 2001,

F AU: astronomical unit, the mean distance from the Earth to the Sun, about 150 million kilometres. Oort Cloud: a hypothetical shell of icy proto-comets that orbit around the Sun, extending almost halfway to the nearest star. Sometimes passing stars cause slight changes in the proto-comets’ orbits, sending them into the inner solar system where we see them as comets. Kuiper Belt: a band of comets or icy asteroids that lies between about 35 and 1 000 AU, in the same plane as the planets.

38 Quest 1(1) 2 0 0 4

astronomers have been surveying the outer solar system using the Palomar QUEST (Quasar Equatorial Survey Team) camera and the Samuel Oschin Telescope at Palomar Observatory in southern California. To find objects, they take three pictures of a small region of the night sky over three hours and look for something that moves. (Satellites, planets, asteroids, and comets seem to move; stars and galaxies appear stationary.) “Vast areas of the sky have to be searched before something this unusual is found,” says Brown. The team was lucky. After looking at only 15% of the sky, they found Sedna in November 2003. Improvements in technology – more sensitive digital cameras and faster computers to analyse data – allow astronomers to find more objects, further away, than they could even five years ago. Name: Sedna, the Inuit (Eskimo) goddess of the sea from which all sea creatures were created, is the name the astronomers propose for this icy body. Its temporary ‘scientific’ name is 2003 VB12. The International Astronomical Union (IAU) Committee on Small Body Nomenclature, responsible for solar system names, needs to approve the name ‘Sedna’.

Position: Sedna is twice as far from the Sun as any other object in our solar system – three times further than Pluto, 90 times further than the Earth, and beyond the reach of almost all amateur astronomers. Situated in the Oort cloud, its current position is 90 AU (see box). “Standing on the surface of Sedna, you can block the entire Sun with the head of a pin held at arm’s length,” explains Brown. Orbit: Sedna’s orbit is extremely elliptical, unlike that of closer planets, and could take it out more than ten times further away from Earth than it is now. Its unusual orbit may be caused by passing stars or perhaps by a larger body (not yet found), about the size of Mars or bigger, existing around 70 AU. Sedna will become closer (76 AU at its ‘perihelion’ or ‘closest distance to the Sun’) and brighter over the next 72 years before starting its 10 500-year trip to the far reaches of the solar system and back again. “The last time Sedna was this close to the Sun, Earth was just coming out of the last ice age; the next time it comes back, the world might again be a completely different place,” observes Brown. Rotation: Sedna rotates slowly – probably once every 40 days or so (only Mercury and Venus are known to rotate more slowly). This could be the

Discovering Planet(oid?) SEDNA

effect of a moon (to be confirmed, astronomers hope, by Hubble Space Telescope observations).

Size: Astronomers cannot measure the size of Sedna directly from the point of sunlight they see on images reflected back to Earth from Sedna’s surface: a small icy object and a large dark object would reflect the same amount of light. They do know that Sedna is about 1 800 km in diameter because, if it were any bigger, they could have seen it with the 30-metre IRAM telescope or the Spitzer Space Telescope.

Classification: The discoverers of Sedna believe it is not a planet but a ‘planetoid’, that is, a round object in the solar system that is not big enough to be considered a planet. Brown defines a planet as “any body in the solar system that is more massive than the total mass of all of the other bodies in a similar orbit. For example, many asteroids cross the orbit of the Earth. Yet the Earth is more massive than all of those put together. Thus the Earth is a planet.” By this definition, Pluto is also not a planet. Found in the Kuiper Belt, it is no more massive than the total of the other Kuiper Belt objects, but is simply the largest object in its class, and may be an escaped moon or an unusual, large asteroid.

Some astronomers define a planet as anything that is made round by its own gravity, orbits a star, shines only by reflected light, and does not have enough mass to become a star itself. According to this definition, our solar system then has hundreds of planets, including asteroids, the Moon, and round Kuiper Belt objects.

Composition: We don’t know what Sedna is made of. Some astronomers think it may be part water ice or methane ice (because it is relatively bright) and part rock. They do know that Sedna is one of the reddest objects in the solar system, almost as red as Mars, but have no idea why. Temperature: Its surface temperature of about -240˚C makes Sedna the coldest known place in our solar system. ■ For more information consult John Gribbin, Companion to the Cosmos (London: Phoenix, 1997) and visit the following web sites: Michael Brown, California Institute of Technology – www.gps.caltech.edu/~mbrown/sedna/ Robert Roy Britt – www.space.com/scienceastronomy/new_object_040315.html BBC – http://news.bbc.co.uk/1/hi/sci/tech/3511678.stm Yale University – http://hepwww.physics.yale.edu/quest/palomar.html Whitney Clavin, NASA’s Jet Propulsion Laboratory – www.nasa.gov/vision/universe/solarsystem/planet_like_body.html International Astronomical Union – www.iau.org/IAU/FAQ/sedna.html California Institute of Technology – spitzer.caltech.edu

Star gazers at SAAO As South Africa prepares to launch its new large telescope, training has begun for a new generation of astronomers, explains Patricia Whitelock of the South African Astronomical Observatory (SAAO). Engineers from the Southern African Large Telescope (SALT) project team are putting the finishing touches to the largest single optical telescope in the southern hemisphere. Meanwhile, astronomers have been busy training a new generation of African astronomers. The task of constructing and perfecting this giant instrument at Sutherland in the Northern Cape has gone on for the past four years. SALT should be ready to begin its working life in early 2005, and tension mounts as astronomers prepare to use it to start exploring the early universe. While engineers were building the telescope, the astronomers were building a corps of astronomers to collaborate internationally with other astronomers and space physicists.

New career paths

Summer School participants in front of SALT at Sutherland

▲ ▲

Based at the University of Cape Town (UCT), the National Astrophysics and Space Science Programme (NASSP) was designed to create an African network of astronomers. It offers postgraduate training for honours and master’s students. Professor Peter Dunsby acts as coordinator, and lecturers come from the entire South African astronomy and space

science community. Graduates in physics are accepted – and in engineering, mathematics, and computer science if they have done enough physics. Generous sponsorship from the Ford Foundation, Canon-Collins Foundation, UCT Vice-Chancellor’s strategic fund, and the National Research Foundation (NRF) has made NASSP possible by providing student bursaries. Many students qualifying from NASSP will go on to do doctorates and further research in optical, radio or gamma-ray astronomy or in the related fields of space physics. Others will move into industry or commerce – taking with them practical skills in problem solving, data analysis, computer programming, and science communication. In 2003, the first year of NASSP, 11 students qualified with honours degrees. In 2004, 14 new students started the honours course and 14 started the M.Sc. The South Africans come from universities around the country: KwaZulu-Natal, Pretoria, Venda, Rhodes, the North, and the North West; others come from as far afield as Ethiopia, Uganda, and Zambia.

Quest 1(1) 2 0 0 4 39

Star gazers at SAAO

▲

The following institutes are partners in NASSP: The universities of Cape Town, the Free State, KwaZulu-Natal, South Africa, and Zululand; North West University; Rhodes University; Hartebeesthoek Radio Astronomy Observatory; Hermanus Magnetic Observatory; South African Astronomical Observatory.

Summer school Most students entering NASSP have no previous experience in astronomy, and the SAAO Summer School provides a comprehensive introduction and lots of fun. The 2004 course was a great success. Organized by Lisa Crause, a Ph.D. student from UCT, the range of activities included: ■ introductory lectures on astronomy, with visits to the planetarium ■ lectures on topics ranging from black holes to the robotic exploration of the planets ■ observing with telescopes, including a trip to Sutherland (a highpoint for many) ■ practical exercises in astronomical calculations, building LEGO robots, and launching rockets ■ useful skills for the future – an introduction to the Linux operating system and scientific programming; written and oral communications; research methods (in the library and via the Internet) ■ science-fiction movies and visits to Kirstenbosch, MTN ScienCentre, Spier Raptor-World, and Thunder City. ■ For more information and images visit: The National Astrophysics and Space Science Programme – www.star.ac.za Southern African Large Telescope – www.salt.ac.za South African Astronomical Observatory – www.saao.ac.za

Puzzle – Calculate from Sedna’s scientific name How many celestial objects were found before Sedna in the first half of November 2003? (Its provisional scientific designation is 2003 VB12.) Naming a celestial object The IAU Minor Planet Center assigns a new provisional designation when it has at least two nights of observations of an object that cannot be identified immediately with some already designated object.

The standard designation has the following parts (all relate to the object’s date of discovery): ■ a 4-digit number indicating the year ■ a space ■ a letter to show the half-month ■ another letter to show the order within the half-month ■ an optional number to indicate the number of times the second letter has been repeated in that half-month. First letter The half-month of discovery is indicated using the following scheme: Half-month Letter Dates period 1 A Jan 2 B Jan 3 C Feb 4 D Feb 5 E Mar 6 F Mar 7 G Apr 8 H Apr I is omitted and Z is unused

1–15 16–31 1–15 16–29 1–15 16–31 1–15 16–30

Half-month period 9 10 11 12 13 14 15 16

Letter

Dates

J K L M N O P Q

May May Jun Jun Jul Jul Aug Aug

1–15 16–31 1–15 16–30 1–15 16–31 1–15 16–31

Half-month period 17 18 19 20 21 22 23 24

Letter

Dates

R S T U V W X Y

Sept Sept Oct Oct Nov Nov Dec Dec

1–15 16–30 1–15 16–31 1–15 16–30 1–15 16–31

Second letter The order in which the object was discovered, within the half-month, is indicated using letters as follows: A B C D E I is omitted

1st 2nd 3rd 4th 5th

F G H J K

6th 7th 8th 9th 10th

L M N O P

Numbers ■ If there are more than 25 discoveries in any one half-month period, the second letter is recycled and a numeral ‘1’ is added to the end of the designation. ■ If there are more than 50 discoveries, the second letter is again recycled, with a numeral ‘2’ appended after the second letter. ■ Discoveries 76–100 have numeral ‘3’ added, numbers 101–125 numeral ‘4’, etc.

40 Quest 1(1) 2 0 0 4

11th 12th 13th 14th 15th

Q R S T U

16th 17th 18th 19th 20th

V W X Y Z

21st 22nd 23rd 24th 25th

Thus the order of assignment of designations in a particular half–month period is as follows: 1995 SA, 1995 SB, ..., 1995 SY, 1995 SZ, 1995 SA1, ..., 1995 SZ1, 1995 SA2, ..., 1995 SZ9, 1995 SA10, etc. IAU, Minor Planet Center – http://cfa–www.harvard.edu/cfa/ps/info/OldDesDoc.html

(Answer on page 48.)

Q Viewpoint

THE PLAGUE OF

Good intentions wrongly applied could be damaging our prospects and our surroundings, observes George Ellis. Where does that leave GM crops, the PBMR, and alien plants?

Like all crop genetic modification, whether resulting from techniques of traditional breeding or more recent molecular biology, GM crops need careful evaluation in relation to the specific environment where they will be used. In some cases – such as the Makatini Flats – they can help smallscale farmers to increase productivity and decrease insecticide or herbicide use. Environmental aspects clearly need evaluation, and in many cases are acceptable or even positive. This is denied by GM opponents, who often resort to questioning the credentials of those scientifically qualified to examine the issue.

Fundamentalism combined with little appreciation of context completely distorts and undermines what true environmentalism should be about. They pursue an untenable twofold attack, claiming, first, that GM crops are too dangerous for anyone to use and, second, complaining that GM seed producers practise economic policies that exclude small-scale farmers from their benefits. These arguments contradict each other. In pursuing the second issue – which is indeed a real concern – they give the game away, for they know that GM crops bring real benefits. What we need is a sound regulatory policy concerning safety and the environment (which South Africa has in place), together with development and economic policies that make GM crops

suited to the local environment and available at affordable prices to local farmers. We therefore need to give strong support to the excellent local biotechnology research groups that are working on these problems with integrity. As regards the PBMR, we must distinguish between safety issues and broader environmental concerns. No plant should be allowed to operate if there were any danger of a Chernobyl type disaster, which occurred in a very different (inadequate) reactor design. The PBMR’s inbuilt safety features make it inherently safer than other nuclear reactors in successful operation today, for example those that have functioned for 30 years in France without serious incident. In any case, the safety of the design will be assessed by the Nuclear Regulator before any plant is permitted to run in this country. The economics of the project, also under attack, is an issue for the entrepreneurs involved in it. Apart from potential sales in the Far East, it looks increasingly likely that the PBMR will play a key role in plans to introduce a hydrogen energy economy in the USA. PBMR opponents ignore the huge environmental damage caused by coalpowered stations – the only serious industrial-scale alternatives to nuclear power, and, specifically, the major contribution to atmospheric pollution and to global warming. Have they ever heard of the Kyoto Protocol on atmospheric emissions? Yes, we’d all like to use solar, wind, hydro, etc. instead, but they too carry environmental and health costs, as well as being expensive. Sure, we should increase our use of them where we can (Eskom is investigating these alternatives). But even the most optimistic projections show they’ll provide no more than 30% of our needs

▲ ▲

aving long been interested in environmental issues, I am dismayed that so much of the environmental movement has become engulfed in an absolutism that restricts, and often destroys. Characterized by fundamentalism combined with little appreciation of context, it completely distorts and undermines what true environmentalism should be about. In South Africa it relates to three significant policy issues: genetically modified (GM) crops, the Pebble Bed Modular Reactor (PBMR), and policy regarding ‘alien vegetation’. ‘Fundamentalism’ is the tendency to view partial truth as the whole truth: to contemplate only a subset of the causal factors in a situation, rather than the whole nexus of interacting causes and effects. What is important varies with context, and effective environmental understanding means being able to see what’s important in specific situations, and make room for social and economic issues, for example, as well as strictly environmental ones. In contrast, fundamentalists offer analysis and remedies independent of context. To defend the resulting highly restricted points of view, they often indulge in personal and political attacks that undermine scientific integrity. Extreme attacks on GM crops, for example, emphasize only the potential dangers and ignore major benefits that can accrue through their use. In Africa, the anti-GM lobby (mainly originating from abroad) resorts to simple deception, labelling GM foods as ‘poison’ despite all the evidence that the crops in question are completely safe for human consumption. They tell Africa’s leaders that the USA used Africans as guinea pigs for foods that Americans would not eat, when in fact they have been widely consumed in America for some 15 years.

ABSOLUTISM

Quest 1(1) 2 0 0 4 41

News Q

Fifteen-year-old NASA winner Nomathemba Kontyo won the Africa leg of the Planetary Society’s Red Rover Goes to Mars essay competition, and spent two weeks in the USA in February and March as a guest of the US National Aeronautics and Space Administration (NASA) in California, together with 15 pupils from other continents. This was a triumph for a young woman living with her family in a shack in Cape Town, and for her school, Fezeka Senior Secondary in Gugulethu. She has decided on a career as a computer scientist or an astronaut. She says, “If you can dream it, then you can do it!” Share her experience through the journals she kept and learn more about NASA’s Mars Exploration Rover mission at www.redrovergoestomars.org/studast.html

South African Women in Science and Engineering (SA WISE) SA WISE has awarded its fifth Angus Scholarship to Melinda Griffiths for study towards her honours degree in cell biology at UCT’s School of Biomedical Sciences. Her particular enthusiasm is for stem cell research. Stem cells can be encouraged to produce different kinds of tissue – skin, pancreatic cells, muscle cells, and nerve cells, for example. They have the potential to help people with diseases such as spinal cord injuries, multiple sclerosis, diabetes, Parkinson’s, and Alzheimer’s. SA WISE’s principle is, “Educate a woman and you educate the next generation” and it aims to strengthen the position of South African women in science and engineering in all kinds of ways. Its work is directed at raising the profile of women scientists and engineers, highlighting and addressing problems faced specifically by women in these career areas, lobbying for the advancement of women in science and engineering, and providing leadership and role models for young people with aspirations in these fields. For details visit www.sawise.org.za

Crime and drugs Housebreaking is down in Britain. Break-ins are now done mainly by desperate, drug-addicted young men targetting properties within walking distance of where they themselves live. Video recorders and hi-fis are too cheap to be worth stealing by professionals. Credit cards, cheque books, cellphones, and cash are better value – people carry these around, so street crime is more common. Police are now connecting particular crimes with particular kinds of drugs. A Home Office study of 3 000 arrestees showed those brought in for burglary and shoplifting prefer heroin, while muggers and bag-snatchers tended to be on cocaine or crack. A crack addict needing a fix will be “climbing the walls” and unable to plan a break-in. As powder and crack cocaine have become more popular than heroin, burglaries could go down and street crime up and up. Reported in The Economist, 29 May–4 June 2004.

42 Quest 1(1) 2 0 0 4

▲

Women on the move

Viewpoint Q

in the foreseeable future. I find extraordinary the myopia that sees only the problems of piles of nuclear waste (that quietly decay away where they are left, and won’t harm you unless you insist on sitting on them), while turning a blind eye to the damage done by thermal power stations that emit their wastes into the atmosphere. We need serious assessment of the benefits and costs of each method – of economic factors as well as environmental damage – without allowing a takeover by emotional reactions to the word ‘nuclear’. As for ‘alien vegetation’, I write of the Western Cape, which I know well. An arbitrary line has been drawn back to 350 years ago, enabling us to forget that fynbos was in its own time an alien invader. The ‘aliens’ brought to South Africa by early settlers came for good reasons: to stabilize the sand dunes on the Cape Flats, and to give shade that indigenous vegetation does not provide. Some aliens turned out to be almost as invasive as the settlers who introduced them, and certainly need to be controlled. But that doesn’t mean we must destroy all shade-giving trees not approved of by environmental absolutists. Was it really necessary to destroy the former wooded area at the Silvermine lakeside? It once gave shelter and pleasure to hundreds of picnickers of many colours. Now those who still venture there need plastic umbrellas to protect them from the summer sun. I love fynbos enough to belong to a private conservation consortium that own some of the best fynbos in the Peninsula, which we keep in prime condition. I love to walk there in the mountains above Simon’s Town. This doesn’t mean we need fynbos everywhere. And shade is an asset in a baking climate. The action of the authorities was simply destructive when they axed the pines at the foot of Kasteel’s Poort that once provided the only shade on a hot day. They were not an invasive threat. Nor were the three trees in a little Northern Cape town – the only ones available to give shade in the heat of the day until they were axed by overzealous officials to the dismay of the town’s hapless inhabitants. No appreciation of context is apparent in the famous argument that the magnificent trees in Newlands Forest should be destroyed because they consume so much water, for in that area water simply runs off into the

stormwater drains of the suburb below. As these trees disappear, the load on those stormwater drains will increase, and result in suburban flooding from time to time. The argument, valid in the case of a water catchment area, is specious where context is disregarded. The oak trees of Stellenbosch and the jacarandas of Pretoria are part of our cultural and environmental heritage. They add richness and value to the landscape. Do let’s get environmental educationists to appreciate complexity and variety, instead of acting as propagandists for simplistic absolutism. ■ George Ellis, Distinguished Professor of Complex Systems in the Department of Mathematics and Applied Mathematics at the University of Cape Town, is also the winner of the 2004 Templeton Prize for Progress Toward Research or Discoveries About Spiritual Realities, which he received from the Duke of Edinburgh in a private ceremony at Buckingham Palace on 5 May 2004. South Africa’s emergence from apartheid into democracy without a race war, says Ellis, was a “confounding of the calculus of reality, beyond the explanation of hard science, including issues such as ethics, aesthetics, metaphysics and meaning.” As a scientist specializing in general relativity theory and its applications to cosmology (the study of the origin and evolution of the universe), he believes that, “as we gaze with amazement and appreciation at the incredible progress of science in the last century, we can also start to see clearly some of the limits to what science can achieve.” The Templeton Award, worth about R10 million, is the world’s largest annual monetary award to an individual. It was set up in 1972 by Sir John Templeton, who specified that its capital value should always exceed that of the Nobel Prizes, on the grounds that advances in spiritual discoveries have greater significance. It aims to foster progress through philanthropy and create a broader understanding of the relationship between theology and science. Part of the award will fund Ellis’s remaining life’s work. The rest will include support for the Basic Income Grant Campaign, the Association for Educational Transformation (ASSET), Quaker organizations in South Africa, and other, smaller communities of “wonderful people who are doing so much for others.”

Q News

Q Quest crossword You’ll find many of the answers in our pages, so it will help to read the magazine before you do the puzzle. 1

6 8

11 12 14

13 17

As electronics in cellphones, laptops, and sensing systems become smaller, so must the cooling systems that keep them from overheating. Researchers at Purdue University in the USA have created the tiniest of fans that use minute voltages to generate ions that discharge to create small breezes – no water or cooling fluids needed. The scale is right for tiny electronic machines. The system’s electrodes are made from carbon nanotubes only five nanometres (5 x 10-9 m) across at the tip. They attract the clouds of ions created when electrons react with air. To ‘pump’ the ions forward, the voltages in the electrodes are changed. The first electrode in a series of three is the most positively charged, the next has a less positive charge, and the third is negatively charged. The voltages are switched rapidly from electrode to electrode (about a million times per second), pushing the ion clouds forward to create the cooling breeze. For details visit Compact High Performance Cooling Technologies Research Center at www.ecn.purdue.edu/CTRC and the National Science Foundation at www.nsf.gov

Cool technology

Microscopic computers to fight cancer in the cell? 27

28 JEMIMA

Across

Down

1 3 8 10

An alien species of bulbous water invader (8) 4 A standard amount of a physical quantity, used for calculations (4) 5 Some species feed on wood and cause damage to furniture, buildings, and trees (7) 6 *Raymond ——, in 1924 discovered and named Australopithecus (the southern ape) from Taung (4) 7 *—— Cloud, a hypothetical shell of icy proto-comets circling the Sun (4) 9 A sandbank, stretch of shallow water, or large group of fish (5) 13 *Ornithologists working in Thailand have heard 7 species of this bird from their cottage (8) 14/25 *In 1936 he discovered at Sterkfontein the first adult Australopithecus, which he named Plesianthropus (6,5) 16 *Another name for 3 Across (6) 17 *The — Herds, a book about cattle 18 *A supporting framework for the body (8) 21 *Newly-discovered planet? (5) 22 A turbine component that shares its name with a leaf of grass, a dashing young man, and a cut of beef (5) 26 * Member of the genus Homo (3)

11 12 15 17 19 20 23 24 25 27 28

*They keep you alert in the rain forest! (7) *Another name for 16 Down (5) *A newly-emergent disease (1.1.1.1) *— Island, a sub-Antarctic South African territory with a weather station (6) Elementary component of molecules (4) *The path described by one celestial body in its revolution about another (5) *Kuiper —, a band of comets or icy asteroids (4) *Large bird, over 40% of its population to be found on 10 Across (9) *Cattle of the Zulu people (5) *Branch of biology that studies heredity (8) *A word meaning ‘ape-like’ (9) *Large poisonous plant of the Verbena family; a bushveld invader (7) See 14 Down Examples include pottery, porcelain, and enamels (7) On a single occasion only (4)

Did you like this crossword? Was it too difficult? Too easy? Just right? Write to the Editor at editor.quest@africa.com and let us know. (Mark your message “CROSSWORD COMMENT”.)

The smallest biomolecular computer in the world might one day enter our bodies to diagnose cancer and other diseases from within the tissue and release drugs to fight them. Having made a computer so tiny that a trillion of them could fit in a single drop of water, Professor Ehud Shapiro and colleagues at the Weizmann Institute in Israel have now (as reported in April in Nature online) programmed it to detect and treat prostate cancer and a type of lung cancer in laboratory trials. Decades in the future, perhaps, instead of biopsies to test for cancer, a minute DNA computer could be administered as a drug. It would follow the bloodstream to detect early signs of disease in every cell, and could be used to deliver drugs to cells that are difficult to reach.

Vaccines against global warming? When cattle and sheep burp, out comes methane (CH4). Like carbon dioxide, it is a potent greenhouse gas, believed to influence global warming significantly. It’s produced in large quantities by bacteria in the digestive tracts of cattle and sheep, then expelled at both ends of the animals. Australian scientists have been working on a vaccine that knocks out these methane-generating bugs, initially in sheep, with encouraging success. They’re now extending their work to a vaccine for cattle, which produce proportionately much more of the atmosphere-heating gases.

Quest 1(1) 2 0 0 4 43

Books Q Right: A mature tricoloured bull, with the short, strong horns and stockiness of a fully-developed male animal.

The naming of The Abundant Herds: A celebration of the Nguni cattle of the Zulu people. By Marguerite Poland, David Hammond-Tooke, and Leigh Voigt (Vlaeberg: Fernwood Press, 2003). Right: The Zulu names maqandakaqelu (for a white beast with red speckles sprinkled all over it) and maqandakacilo (for a white beast with small red speckles) are connected with the eggs (amaquanda) of birds. The eggs of the Richard’s pipit (that is, kaqelu) are lightly speckled with rusty red. Rufousnaped lark’s eggs have small red speckles and it is assumed that ucilo refers to this bird, which is prominent in Zulu folklore.

Right: Animals termed intulo (meaning a type of lizard about the same size as a chamelion) may be black, dark brown, or red, and distinctively speckled at the top of the rump and on the head. In Xhosa, this name means ‘reduced to poverty or nakedness’. The story goes that the Creator had wanted to make people immortal, and sent the chameleon to take this message to humankind. But the chameleon tarried along the way, so, in anger, the Creator sent a second messenger, the lizard, to bring the message of death instead.

44 Quest 1(1) 2 0 0 4

his book, as the title suggests, celebrates the Sanga Nguni breed, for so long dismissed by South African farmers as ‘scrub cattle’. It also, for the first time, uncovers and illustrates through the artwork the intricacies of the poetic yet practical indigenous Zulu naming system that classifies these animals according to their particular colour patterns. With her background in African languages and talents as a novelist, Marguerite Poland set out to explore “the world of cattle and their poetry, and the way in which they are perceived and celebrated, not only by the Zulu people, but by the pastoralists of Africa.” Her researches led her to discover that the complex names of the animals, related to their colouring, metaphorically link the appearance of the different beasts with birds, animals, plants, and other familiar phenomena: “The perception and celebration of nature in general, and the facility to create, in complex poetic compound noun structures, the most apt images and descriptive phrases, is one of the special beauties of the indigenous languages of Africa.” The careful naming of cattle defined the identity of property of great value to the Zulu people. Anthropologist David Hammond-Tooke explains that it not only “reveals the extraordinary intimacy between the Zulu family and its herd” but also reflects the part that cattle have always played in important aspects of Zulu life – economics, politics, kinship, religion, marriage, and health. Colour-pattern terminology, Marguerite Poland discovered, is a classification system devised to identify a number of recurring colour patterns genetically present in Nguni cattle (not to be confused with international scientific classification systems) and arises out of aesthetic constructs in

Q Books New books Medicinal Plants of the World. By Ben-Erik van Wyk and Michael Wink (Pretoria: Briza, 2004).

the imagination of the Zulu people. The role of analogy in this oral tradition makes the names easier to memorize and convey to others, and the name of a class of animal whose appearance reflects that of a lizard, or houses, or specific eggs of birds, for instance, is understood and recognized by an entire community. Individual animals can also receive further distinctive names that are not part of this classification system, but that describe some attribute or episode in the animal’s personal history. If it is being used for a specific purpose, such as lobolo, when cattle are exchanged between families at the time of a marriage, for example, the animal may receive a further name designating its role in these transactions. The term imvulamlomo (‘what opens the mouth’) may be added for a beast presented to the bride’s parents by the prospective groom’s people to pave the way for negotiations. The oral art of naming Nguni cattle is perfectly rendered in Leigh Voigt’s paintings of individuals and herds. Her pictures illustrate the keen visual imagination that linked the colour pattern of, say, a black beast with a white head, with that of the fish eagle from which the animal received its name. The visual images, combined with textual explanations, graphically reveal the logic of the classification system – as they do instances of ambiguity, which, in Hammond-Tooke’s words, are settled “in the pastures themselves where proud owners spend hours discussing animatedly the correct name to apply to a particular beast.” The book highlights anew the practical value of these indigenous animals, which, explains Hammond-Tooke, over 2 000 years of close relations with people, have evolved their characteristic hardiness, “excellent meat and milk yield and resistance to parasites,” as well as their docility and their “habit of keeping together in a group while grazing, thus facilitating herding.” The celebration of the cattle of the Zulu people, in this volume, is also a celebration of the poetic metaphor at the heart of their aesthetic sensibility and cultural heritage. ■ For more, see also “Bountiful Nguni herds”, South African Journal of Science, vol. 99 (2003), pp. 517–520. Read Marguerite Poland’s novel, Recessional for Grace (2003) for a fictional rendering of the author’s relationship with Nguni cattle and their symbolism, transferred back to the South Africa of half a century ago.

Above: A white beast with a pattern of medium-sized, circular black patches scattered over its sides is thought to resemble a view of homesteads from a distance. Its name, indlu/izindlu, comes from the words inkomo (a beast) and eyezindlu (of the houses). Paintings: Leigh Voigt

More news of The Abundant Herds ■

There is an exhibition of the paintings in the Thomas Pringle Hall at the Grahamstown Festival from 1–10 July, courtesy of the Oppenheimer Trust. ■ Nicholas Ellenbogen’s play, Nguni: A Love Story, is on at the Grahamstown Festival and then tours the country. ■ Local film-maker, James Hersov, inspired “by this wonderful book”, is making a film aimed at the international market and due for release in mid-2005. It will be shot in the Zulu heartland of KwaZulu-Natal. “The focus,” he explains, “is on integrity and accuracy. It is a poetical and lyrical rendering, rather than a hard anthropological documentary.” ■ Limited edition prints of 14 of the oil paintings, and posters featuring 40 of the most interesting colour patterns, are available. For information, visit www.nguniprints.com

Meticulously researched, with over 800 fullcolour photographs, this reader-friendly guide describes more than 320 of the world’s bestknown and most important medicinal plants and their relatives. Each entry gives a brief description of the plant, and its geographical origin, therapeutic category, historical and modern uses, active ingredients, and pharmacological effects. There are chapters on healing cultures of the world, and on common ailments and their treatment with modern phytomedicines and traditional remedies. There’s also a quick guide and checklist of some 900 commercialised medicinal plants, and a glossary of chemical, medicinal, and pharmaceutical terms. “Medicinal plants are an important part of human history, culture and tradition,” say the authors, reminding readers that it took science 200 years – once vitamin C had been discovered – to understand why lime fruits given to British seamen had for so long led to their recovery from symptoms of scurvy: “Let us not be too sceptical about seemingly outrageous claims that are sometimes made about particular plants. ... It is likely that some traditional medicinal plants included here hold the key to new advances of great importance to human health.”

Guide to the Aloes of South Africa (2nd edn.). By Ben-Erik van Wyk and Gideon Smith (Pretoria: Briza, 2003). The growing popularity of aloes has encouraged the authors to revise their earlier field guide. In addition to descriptions and photographs of all 125 species of aloes occurring within South Africa, this new edition adds information for wider audiences. It updates classifications and gives the scientific names of the aloes as well as Imperial equivalents of metric measurements. A most useful addition is the new section on landscaping with aloes, to help gardeners and horticulturists make the most of these plants. Their shapely leaves and the bold colours of their flowers make them an excellent choice for borders, hedges, and rockeries; they thrive even in the harshest conditions, and – a further advantage – they need very little care.

Have you read this? Rebirth of Science in Africa: A Shared Vision for Life and Environmental Sciences. Edited by Himansu Baijnath and Yashica Singh (Hatfield: Umdaus, 2002). This book brings together the work of local and international scholars who have applied their expertise to Africa’s needs.

Quest 1(1) 2 0 0 4 45

News Q USA losing dominance in science? Many countries, not least South Africa, complain that too many of their brightest graduates, especially in science and technology (S&T), are tempted to become part of a ‘brain drain’ that takes them abroad for more attractive employment opportunities. For many, the grass seems greenest in the United States. But times are changing. American dominance in science, although still a potent force, is evidently not what it was. Among the indicators of a decline of influence is a fall in the proportion of American authors in the top research journals. For example, the fraction of American papers in Physical Review, a leading series of physics periodicals, has halved over the past two decades to just under 30%. In the mid-1990s, Europe surpassed the USA as the world’s largest producer of scientific literature. And Americans no longer win as many Nobel prizes – another measure of excellence in science – as they once did: their share has fallen.

Patents indicate industrial activity. The American share of its own industrial patents is declining in the face of rapidly expanding industrial activity in Asia. For example, more than a quarter of US industrial patents have lately been awarded to researchers in Japan, Taiwan, and South Korea. These Asian contributions, in terms of both quantity and quality, are growing rapidly. Increasingly, China’s influence is being felt. If America is slipping in S&T it is not for lack of funding. US government science budgets are at record highs: this year, more than US$126 billion has been allocated to research. Spending on military research, at $66 billion, another source of innovative technology, has never been higher, but the right people are also needed. A US government-commissioned report, released in May, noted a “troubling decline” in the number of Americans training to be scientists and engineers. Ironically, the problem arises partly from

a growing demand for technical skills as a result of the economic success that created these opportunities in the first place. Today, however, the USA ranks 17th among nations in the share of its 18-to-24-year-olds who earn degrees in the natural sciences and engineering, whereas thirty years ago it ranked third. Skilled foreigners, contributing to the brain drain in their own countries, have filled the gap for decades, and today, nearly 4 in 10 of all US scientists and engineers with doctorates were born outside the USA. But as more countries, especially in Europe and Asia, recognize S&T as crucial to economic growth and prosperity, they will be creating employment opportunities to compete with traditional centres. The rest of the world is catching up on the established bastions of influence: scientific excellence is no longer the prerogative of the old order. All these trends will affect South Africa in one way or another.

powered by temperature differences. See full-size working replicas of the 1899 steam-powered wagon, the ‘Stanley Steamer’, and the petrolpowered motorcar, the Benz (1886). Marvel at the first Bell telephone in South Africa and futuristic robots. Highlighting more than 200 inventions through the ages and the people behind them, this exhibition shows science and technology to be accessible and relevant to all of us, every day. For school groups, there are workshops to support two new learning outcomes in the Revised National Curriculum in the Natural Sciences: Scientific Investigations and Constructing Science Knowledge.

contributions to world technology. MTN ScienCentre’s ‘Proudly South African’ major travelling exhibition and series of educational workshops and demonstrations showcases great South African inventions of the past 3.5 million years, from traditional knowledge and early pioneering inventions to modern high-tech advances. It also supports learning outcomes in the new National Curriculum in the Natural Sciences.

Until 31 July. Tel.: (021) 529 8100 or visit www.mtnsciencentre.org.za

3 September – National Arbor Day

Diary of events Q Sci-Bono Discovery Centre (Miriam Makeba, Newtown, Johannesburg)

“A Question of Truth”, an exhibition from the Ontario Science Center in Toronto, Canada. Question the science around us – see if you can pass the ‘hip-hop IQ test’; uncover bias in research; and compare western and alternative sciences. Step into the ‘confinement box’ and experience what it felt like to be an African slave on a ship bound for the New World. Find out about genes. Until end December. Tel.: (011) 832 3363; e-mail: info@sci-bono.co.za

MTN ScienCentre (Canal Walk shopping centre, Cape Town)

Travelling exhibition

“Great Inventions that Change your World”, sponsored by the Shuttleworth Foundation. Learn how to make a fire with a fire stick, operate an Archimedes screw as the ancient Egyptians did, and use the heat of a hand to turn a Stirling engine that’s

“Great South African Inventions” 15 August–31 December (in Cape Town in August and other provinces from September onwards). Find out how to be an inventor (even in a modest way), see the play, Eureka – I found it! and celebrate our country’s

46 Quest 1(1) 2 0 0 4

For bookings and more information, tel.: (012) 529 8100 or visit www.mtnsciencentre.org.za

Plan for 16 September – World Ozone Day

Diary of Events welcomes news of science and technology events or happenings. Send full details under the heading “QUEST DIARY” to The Editor, tel./fax: (011) 673 3683 or e-mail: editor.quest@iafrica.com

Q ASSAf News

Science-for-Society Gold Medals

A new world science system

Each year, ASSAf awards two gold medals for outstanding achievement in the application of scientific thinking in the service of society. The first medals were presented to Professor Malegapuru Makgoba and Professor Trefor Jenkins by Dr Ben Ngubane, then Minister of Arts, Culture, Science and Technology, in Pretoria on 30 September 2003. The Academy’s council is now evaluating this year’s nominations. The presentation of awards will take place in Cape Town on 29 October 2004. Professor Makgoba, Vice-Chancellor of the University of KwaZulu-Natal, was cited for his contribution to medical science in South Africa. As chairperson of the board of the Medical Research Council (MRC) and then as its president, he guided the MRC’s transformation and expansion. Standing for scientific integrity, he guarded the reputation of South African science and medicine. As a scientist, Professor Makgoba has been instrumental in demonstrating the importance of surface adhesion molecules in the function of cells (T lymphocytes) that play a central part in the body’s immune system. This work has contributed permanently to our understanding of lymphocyte function.

In Mexico City, from 1–5 December 2003, at a general meeting and Science for Society conference of the InterAcademy Panel (IAP) attended by ASSAf president Professor Wieland Gevers, it became apparent that a new kind of ‘world system of science’ is evolving. The IAP views national science academies as crucial components of the science systems in their countries and the one that is evolving in the world. The combined potential for remarkable economies of scale and empowerment within a coordinated system is based on the recognition of three distinct, complementary domains: those of the science academies, of single scientific macrodisciplines, and of national governments and their (directly controlled) agencies. • Science academies have gone global through international bodies such as the IAP (and IAC) and TWAS (see box), which gather member national academies from around the world to work together. • The domain of single scientific macrodisciplines involves global collaborative projects, such as the International Geophysical Year, which bring national disciplinary associations together in a framework of ‘international science unions’, largely organized by the International Council for Science (ICSU). • At government level, the United Nations (and the United Nations Educational, Scientific, and Cultural Organization [UNESCO]) play a worldwide coordinating and commissioning role. (NEPAD and the African Union are examples of regional and continental intergovernmental bodies.) The newly evolving world science system offers opportunities to harness these three domains globally and regionally. For greatest effect, individual components – such as national disciplinary associations and science academies, or government departments and other bodies in a country or region – need to work well together, and to understand the special contribution to be expected of each. Once governments, for example, start seeing their national science academies as the main providers of advice about science-based issues, academies can respond appropriately. They can do so even better helped by reliable, established networks of regional and global academy support and collaboration. Continental organizations wanting valid, wideranging advice – such as NEPAD – have a ready-made regional science academy system to turn to within the larger framework of the international science academy system. ■

Malegapuru Makgoba

Trefor Jenkins

Professor Jenkins studied medicine at King’s College and Westminster Hospital in London before moving to southern Africa. His genetic research on blood groups and DNA polymorphisms has added significant new insights to the study of gene markers in different populations, which contributed to clarifying the origins of indigenous groups in Africa. He has also worked on sickle cell anaemia and the molecular basis of albinism. Apart from two books, he has authored and co-authored more than 300 scientific publications. Professor Jenkins was a pioneer in establishing an undergraduate teaching programme in medical ethics at the University of the Witwatersrand, where he was head of Human Genetics for many years. He retired as full-time professor in 1997 but continues to teach at Wits Medical School.

For details visit ASSAf at www.assaf.ac.za, the IAP at www.interacademies.net/iap, and the IAC at www.interacademycouncil.net

The IAP, the IAC, and TWAS The IAP embraces the science academies of 90 countries and is hosted in Trieste, Italy, by the Third World Academy of Sciences (TWAS), itself an international science academy for developing countries, with over 700 Fellows, including 17 Nobel prizewinners. The IAP has formed an InterAcademy Council (IAC), which carries out major studies of science-based issues using the best talent available to it from across the globe. At the meeting in Mexico City, ASSAf took part as a member of the IAP and as the sole African member elected to the 15-member IAC other than the multi-country African Academy of Sciences. The IAP (with its IAC) is the global body that connects and represents the national science academies and their regional organizations, while TWAS is a multi-national science academy of developing countries that, Fellow-for-Fellow, is equivalent to the academies of the USA, UK, France, Germany, and Japan.

National academies as world players For national academies to be globally effective, they need to be: ■

■ ■

self-elected, merit-based, activist, ‘science-for-society’ bodies representing all disciplines supported and recognized by their own governments professional and competent in conducting authoritative studies that assess the science behind societal problems and opportunities functionally connected to national disciplinary science associations well organized and active at regional levels.

ASSAf’s position ASSAf was designed as a national, merit-based, activist, broad-based science academy. It is supported by the IAP and IAC leadership, connected to TWAS, and a founder member of the Network of African Science Academies (NASAC). ASSAf is proud to play its part in the evolving new world science system within South Africa and internationally.

Quest 1(1) 2 0 0 4 47

Back page science Q Battle of the sexes Astronomer Cecilia Payne-Gaposchkin (1900–79) was an undergraduate in Cambridge just after the First World War. As the only woman in misogynistic Ernest Rutherford’s lectures, she was forced to sit by herself in the front row. In the laboratory she recalled the explosive and terrifying Dr Searle, who was impatient with women students – though he trained them well in all types of precise measurement and in handling data correctly. He said they disturbed the magnetic equipment and would order them to “Go and take off your corsets!” as steel was then beginning to replace whalebone as a stiffening agent. Women needed real dedication to stay on. In her memoirs, Cecilia Payne advised aspiring scientists never to “undertake a scientific career in quest of fame or money. There are easier and better ways to reach them. Undertake it only if nothing else will satisfy you; for nothing else is probably what you will receive.”

Tearoom stats An episode in a staff common-room inspired Ronald Fisher, one of the founders of applied statistics, to consider the principles that led to his treatise Statistical Methods for Research Workers (1925). He had joined the Rothamsted Experimental Station, near London, in 1910. Not long after that, one afternoon, he offered a cup of tea to Dr Muriel Bristol, an authority on algae and the first woman staff member in the laboratory there. She refused it, saying she preferred the taste when the milk was added to the tea, rather

then when the tea was added to the milk. A blind tasting followed, and Dr Bristol demonstrated that she could indeed tell the difference, although with what statistical certainty is not known. This episode encouraged Fisher to start examining the principles of statistical evaluation. He subsequently developed methods, used to this day, to analyse biological data and to design undertakings such as clinical trials of drugs.

High hopes ■ Biologist Edward O. Wilson once said: “Science consists substantially of finding an entry point, and even a small advance following a breakthrough would be regarded as science of the first class. What’s unreasonable is then to demand that the people who are doing the very early work come up with a whole explanation of everything. That’s crazy.” (Quoted by Jonathan Weiner in the New Yorker (2000).) ■ Neurologist Oliver Sachs, evacuated from London during World War II as a child, found consolation in mathematics for the turmoil around him and for his feelings of being divided, alienated, and broken down: “For me, the refuge I found at first was in numbers. I liked numbers because they were solid, invariant; they stood unmoved in a chaotic world. There was in numbers and their relation something absolute, certain, not to be questioned, beyond doubt. ... I particularly loved prime numbers, the fact that they were indivisible, could not be broken down, were inalienably themselves (I had no such confidence in myself ....).” (In “Brilliant Light”, New Yorker (2000).)

Special wisdom “In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual.” Physicist and astronomer Galileo Galilei (1564–1642).

Profits from science? When Michael Faraday (1791–1867) demonstrated the newly discovered phenomenon of electromagnetic induction, William Gladstone, then Britain’s Chancellor of the Exchequer and in charge of the country’s finances, asked, “What use is it?” Faraday replied, “I don’t know, but one day, sir, you may be able to tax it”. How right he was. The discovery of this principle – the result of what we’d call today curiosity-driven or ‘blue skies’ research – forms the basis of thousands of millions of electric motors used round the world in motor vehicles, computers, and household appliances such as hairdryers, electric mixers, and shortwave radios. Answer to Puzzle (page 40) Calculate from Sedna’s scientific name: 2003=discovery year; V=Nov 1–15 (1st half month); 12=12x25=300 objects; B=2nd object after the 300. The answer, therefore, is 301. Answers to Crossword (page 43) ACROSS: 1. Leeches, 3. Inuit, 8. SARS, 10. Marion, 11. Atom, 12. Orbit, 15. Belt, 17. Albatross, 19. Nguni, 20. Genetics, 23. Pithecoid, 24. Lantana, 27. Ceramic, 28. Once DOWN: 2. Hyacinth, 4. Unit, 5. Termite, 6. Dart, 7. Oort, 9. Shoal, 13. Hornbill, 14/25. Robert Broom, 16. Eskimo, 17. Abundant, 18. Skeleton, 21. Sedna, 22. Blade, 26. Man

Subscription form 2004 I would like to subscribe to 4 issues of QUEST: Science for South Africa. My details are (please print): Title:

Name/Initials:

Surname:

Company/university/institution/school:

Student number (to qualify for student rates):

Postal address: Code: Work Tel: (

)

Cell:

Fax: (

)

Home Tel: (

)

e-mail:

Subscription rates (4 issues incl. postage) Please tick appropriate rate. South Africa (incl. VAT) Neighbouring countries (Southern Africa) Foreign

❑ ❑ ❑

Individuals – R 80.00 Individuals – R160.00 Individuals – R180.00

❑ ❑ ❑

Students/Schoolgoers – R 40.00 Students/Schoolgoers – R120.00 Students/Schoolgoers – R140.00

Payment options Please select and tick your payment option below.

❑ ❑

CHEQUE: Enclose your cheque in South African rands made payable to QUEST MAGAZINE (together with this completed Subscription Form) DIRECT DEPOSIT: Use reference QUEST SUB on your deposit slip and deposit your subscription as follows: Bankers: Standard Bank Northcliff Branch code: 006305

Account Number: 200 5222 05 Account name: Quest Magazine

THEN POST this completed Subscription Form together with your cheque or a legible copy of your cheque/deposit slip to: QUEST MAGAZINE, PO Box 5700, Weltevreden Park 1715, South Africa OR FAX the Subscription Form together with deposit slip to: QUEST SUBSCRIPTIONS (011) 673 3683.

ENQUIRIES should be marked “QUEST Subscription Enquiries” and addressed to Neville Pritchard. Postal address: PO Box 5700, Weltevreden Park 1715, South Africa. Tel.: (011) 678 7093, fax: (011) 673 3683, e-mail: pritchardn@mweb.co.za

48 Quest 1(1) 2 0 0 4