Copyright Sociological Research Online, 1999


Mark Harvey (1999) 'Cultivation and Comprehension: How Genetic Modification Irreversibly Alters the Human Engagement with Nature'
Sociological Research Online, vol. 4, no. 3, <>

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Received: 15/9/1999      Accepted: 22/9/1999      Published: 30/9/1999


Genetic engineering is placed in the context of a history of transformations of the relations between 'cultivated nature' and 'naturally occurring nature'. It is argued that genetic modification is a bio-socio-economic process, producing new diversity within cultivated nature. Viewing bio- science and technology as 'socially embedded', it argues that different trajectories of their development have both the much trumpeted negative possibilities of ecological disaster and a positive potential of revolutionising both the culture of food and eco-sustainability.

Agribusiness; Culture/nature; Genetic Modification; Nature Fundamentalism; New Foods; Techno-scientific Trajectories


Let me be clear on four points.

Bio-socio-economic diversity

This paper sites genetic modification in the continuing historical interaction between cultivated and 'naturally occurring nature'. It takes the tomato[2] as a prism through which to explore this interaction, culminating in the appearance of genetically modified tomato purée on UK supermarket shelves in the mid-1990s.

At the 1998 Annual Conference of the UK Tomato Growers Association, a representative from Novartis, a major European agrochemical and biotechnology company, described how the company's technical experts in developing new varieties of tomato were scouring the Andes for particular disease-resistant strains of wild tomato to cross with contemporary hybrids. There is something distinctly ironic in this 'return to the Andes' by global agribusiness. For, the Aztecs are thought to be the first people to have domesticated the tomato, from Andean strains, and it was in Mexico that Europeans first encountered tomatoes and salsas in the mid-16th century (Smith, A.F., 1996, 1994). Before that, the tomato was not part of European cuisine (Santich, 1995) or agriculture.

The return to the 'origins' can therefore be seen as phase of the ongoing dialectic between wild nature and cultivated nature, between human socio-economy and physical organic nature, both human and non-human. As a consequence of these historical interactions, many new modes of cultivation and consumption of the tomato have emerged. Varieties of cultivated tomato inhabit varieties of culture and production. Although it can be argued that globalisation has brought about homogenisation of agricultural crops (Busch, et al., 1991), what remains striking is how different 'social ecologies' persist as we approach the millenium. Thus the US fresh tomato industry, especially its centre in California, produce a distinct variety of tomato adapted to mechanical harvesting when still semi-green. This tomato variety, moreover, was bred following immigration legislation which restricted the use of Mexican braceros (Friedland and Barton, 1975, 1976). The green tomatoes are then treated with ethylene gas in a ripening process, the kind of process which prompted Friedland to remark that the concept 'fresh' when applied to food is related to technologies of manufacturing freshness, including sterilisation, packaging in artificial gases, and so on (Friedland, 1994). Different varieties of tomato inhabit the North European glasshouse production regime, which in turn have a distinct definition of what makes 'fresh' 'fresh' from Southern European cuisines, production systems, and their tomato varieties. Thus, in spite of the apparent 'universality' of Mendelian hybridisation techniques, diversity reigns. So, to close these examples, the golden midi-plum tomato-on-the-vine can be said to find its most natural habitat on the supermarket shelves of Tesco or Sainsbury. It was bred for that 'niche'.

It will be argued that these differences in 'socio-economic ecology' have played a significant part in conditioning the different trajectories of genetic modification in the US and Europe. But, here I shall pause to assess the significance of this variety, and suggest ways of how to approach it, so as to be better able to grasp the development of biotechnology. In view of the current furore surrounding 'the natural', with supermarkets outbidding each other to present more 'natural' produce[3], and green (Soil Association, Friends of the Earth, Genewatch) or red-green (Benton, 1996) 'nature fundamentalists' springing to the defence of 'nature', it is important to be clear about what is, and what is not 'natural' or 'un-natural' about both the new technologies and those they are destined to supersede. It is equally important not to lump all genetic modification together as one unified phenomenon. There are many different forms of GM, and many different directions it can take.

The essential feature of the dynamic for the emergence of new biological varieties, is that it is a bio-socio-economic process, and not just a socio-economic one. The 'bio' or 'eco' is an integral part of the 'dialectic' signalled above. Moreover, it has two sides: human physiology, both as labourer and ingestor (see Fine, et al. 1996, 1998), and the biological species and ecology they inhabit. As objects of transformation, plants (and animals) are subject to natural laws, and whatever modifications are made of them, the modifications are of organisms subject to those laws, rather than modifications of those laws. Thus, if genetic modification can be said to be historically the most radical form of cultivation, nonetheless it cannot produce non-natural entities. Modifications can make plants or animals die. The outcome of the modification has to be able to live, in order to be either economically or ecologically viable.

But secondly, the socio-ecology inhabited by humans is largely cultivated nature, which, although not 'naturally occurring' or 'naturally natural', is not 'un- natural' either. The plants and animals, the soil and the nutrients, even in some cases the climate and atmospheres, that constitute cultivated nature would never have existed but for massive human intervention over several millennia. Today, many of the cultivated species would not, or could not, sexually reproduce without human assistance. Most cannot be said to 'grow naturally', in the sense of growing in a naturally occurring manner. And yet, they are natural, and nature is no less natural for being cultivated. As one seed manufacturer involved in using non-GM recombinant DNA technology for hybridisation put it: all the species of dog that roam our social ecologies would not be there but for humans, but that does not make them any the less animal. In evolutionary terms, there has been human rather than natural selection for the multitude of cultivated species that inhabit this planet. Cultivated species have long cohabited a planet with 'naturally occurring' species.

Of course, many human interventions, such as burning fossil fuels, the agro-chemical regime which predominates cultivation today, or the slash-and-burn agriculture driven by economic crisis and poverty, can produce unintended and in some cases disastrous consequences. It is also clear that genetic modification could possibly pose a similar risk, were it to be developed without regard to possible unintended consequences. But, and this is the central underpinning argument of this paper, the development of a sustainable socio-economic-ecologies is more likely to be assisted by the advance of biotechnologies and the scientific understanding that accompanies them than by attempts to prevent that advance by posing as human champions of 'natural nature'.

The working through and development of molecular biology in conjunction with genetic modification and non-GM hybridisation technologies, however, is primarily a change within cultivated nature. This change necessarily involves new interactions between cultivated and non-cultivated nature. But whether in terms of human nutrition or in terms of 'unintended consequences' arising from genetic pollution, there is little to suggest that the new interactions are more deleterious than those of the dominant agro-chemical regimes, and there is much to suggest that advances in understanding of genomes and gene expression enable a better understanding of those interactions.

Finally, to conclude this section, if genetic modification is seen as a further transformation within cultivated nature, it is possible to see it as both a continuation and a radical new departure. Proponents of GM tend to stress that nothing has changed, and that GM is merely an extension of cultivation procedures that have been developing since the Egyptians, 2000BC, (House of Lords, 1998, para7, Appendix 1). Opponents tend to argue that GM is a radical break, creating Frankenstein foods, crossing vegetable with fish, and so posing a threat of a new dimension (Greenpeace, Friends of the Earth). In arguing that the crucial break involved in GM is between hybridisation based on phenotypic selection and the science of recombinant DNA with its associated technologies, it can be seen that the starting point of the new is embedded in the end point of the old. Nowhere is this clearer than in the development of the genetically modified tomato, to which I now turn.

The Tomato and Genetic Modification[4]

The issues raised by GM tomatoes are many and complex (Harvey, 1999), and here four themes will be singled out, for the sake of firstly developing the argument sketched above, and secondly, clarifying what is at stake with genetic engineering and, more broadly, recombinant DNA technology. These are:

The emergence of the genetically modified tomato.

Since the launch in 1996, over two million cans of genetically modified tomato purée have been sold in the UK, clearly labelled, and, if market research is to be believed, preferred by consumers both for higher quality and for the 15% lower price. What is distinctive about this GM food is that the genetic modification was modifying the quality of food itself, not modifying a crop in order that it can be sprayed with chemicals. Worldwide, it can be claimed to be the first GM food for food's sake. The effect of the modification was to delay ripening, improve fruit quality, increase viscosity, and so to lead to a reduction in waste during the production process. The result was a denser and tastier tomato paste.

Yet at the outset, none of the leading players involved were even engaged with tomatoes. Zeneca, the leading agro-chemical and biotechnology company, had been strategically acquiring seed companies, but not for tomatoes or horticultural crops. Neither of the principal scientists, first Don Grierson, and later Peter Bramley, had been researching tomatoes.

However, there were many 'natural' characteristics of the tomato which lent it to genetic engineering, such as the distinct phases of its pattern of growth, fruiting and ripening. But one of the decisive features was that the tomato already had a well-defined Mendelian map of its genetic characteristics, as a consequence of decades of commercial hybridisation. A lot was known about specific gene traits, providing a crucial platform for furthering subsequent scientific understanding through use of recombinant DNA technology. Subsequently, the two forms of characterisation, Mendelian and DNA sequencing have been mutually consolidated, the former paradigmatic understanding being absorbed into the latter (Tanksley, 1993; Zabel, et al. 1993)

There are two points to be made about this. First, the object of science was already 'encultured' nature. As with cultivated nature, this point does not support a social constructionist view of science: although subject to human transformation, the 'Mendelian tomato' behaves as it does irrespective of its human characterisation, and hybrid traits, although effects of human intervention rather than natural selection, were nonetheless also natural properties of tomato plants. Second, the object of science was already an economic object. The tomato in question was a commercial variety. As has been argued about the earlier Mendelian agricultural revolution in scientific breeding, agricultural technical knowledge forms a significant background context to the development of particular trajectories of scientific development (Kimmelman, 1992). So, from these two points it can be seen that even at the level of fundamental science, the interaction with nature is with an 'encultured' and contextually 'economic' nature, rather than a pristine or 'innocently natural' nature.

Given these characteristics of interaction, the development of the fundamental science meshed with the development of a commercially exploitable technology. Although at the outset, no precise commercial product was pre-figured in anyone's blueprint, there was a shared assumption that something would emerge, even if it took twenty years to do so, from inception to fruition. The advance in the fundamental science related to developing genetically modified tomato purée was that plants (humans too, incidentally) are now understood to be genetically programmed to senesce. They do not simply die naturally by decay. This was a major scientific discovery. Genetic modification of senescence, by slowing down or stopping the breakdown of cell walls or suppressing the production of ethylene, further extended understanding of processes of senescence (Grierson 1996). At the same time, however, the ability to manipulate senescence, to delay or alter it, was 'economically interesting'. Eventually, Zeneca decided that by arresting the breakdown of the pectin chain (the trait controlled by the polygalacturanase gene), a denser and more viscose tomato would be produced. A deal over the use of the relevant DNA sequence with Calgene, the US biotechnology company, led to the Flavr Savr fresh tomato appearing in America, whilst Zeneca took the better option by going for processed tomato, where the GM tomato enhanced the processing and end product, the GM tomato purée.

I would argue that the boundaries between fundamental science and technology are a lot more 'fuzzy' and unstable than they are often characterised (Star, S.L. 1992a, b; McKelvey, 1996, 1997). But, perhaps the very term 'genetic engineering' used to embrace both signifies a peculiarly high level of interpenetration between the science as pure, public, universal and 'dis-interested' and the engineering as applied, goal-oriented, and constrained by clear conception of economic outputs. This may account for some of the disquiet surrounding genetic modification.

Different socio-economic trajectories of genetic modification

Following this view of science and technology as a 'socially embedded process' which takes as its object an already modified nature, at another level there are differentiating socio-economic processes leading to quite different bio-socio-economic trajectories taken by GM technology in general and GM tomatoes in particular. Although the argument cannot be developed here in detail, I shall advance the 'Monsanto-Zeneca' hypothesis in general schematic terms before returning to the limited aspect of these trajectories: how a GM tomato goes to market[5]. The Monsanto-Zeneca thesis can be stated boldly. In the US, GM has been developed in a context where agribusiness companies are strong, and retail outlets are relatively weak. The regulatory frameworks in the US reflect this power relationship. Monsanto developed its programme for GM crops with one market in mind: agribusiness. The consumer, including consumer ideology of nature, did not figure in its landscape. The primary linkage was between its own and pre-established agro-chemical systems of agricultural production and the new biotechnology. In the UK especially, GM has been developed in a context where supermarkets and retailers have become decisively more powerful in relation to the upstream supply chain over the past twenty years. Regulatory frameworks have been shifting, especially after a decade or more of food scares, to reflect increased sensitivities of the consumer market.

The current turbulence surrounding GM is partly explicable in terms of the global clash between these two different capital power-configurations and their respective regulatory regimes. The battleground is already being prepared within the World Trade Organisation: entry and barriers to entry of GM crops into world production systems and product markets are likely to result in adaptations of regional regulatory systems, both defensively and offensively, in a way that will fundamentally condition future trajectories of recombinant DNA science and technology. In this respect, in the long term there are unlikely to be local or national GM-free zones.

Within this context, however, the bio-socio-economic variety of GM tomato developed by Zeneca has its distinctive characteristics. It was developed not as a vehicle for selling brands of agro-chemicals, but as a food with enhanced food and processing characteristics. Moreover, at a very early stage, negotiations were undertaken with supermarkets in order to define the nature of the product. Both Sainsbury and Safeway took strategic decisions to market the purée as an own-label product, so putting their reputations on the line. All parties were agreed that GM tomato purée would be segregated and labelled, so that the consumer was given a clear choice. Zeneca have also been quite clear that, although originally taking advantage of the more permissive US regime for the production of its GM tomatoes, it needed to establish confidence and acceptance within the regulatory regime and consumer markets of Europe, and therefore needed to develop production in Europe to do so. Their GM tomato is to be a European GM tomato, not an import risking fears of contamination from different regulatory and consumer regimes.

Nutrient Dense Food and second generation genetic modification

You can walk into a Boots high street drugstore today and buy a packet of Mediterranean tomato lycopene tablets promising the health benefits of a sun-soaked climate. Lycopene is an anti-oxidant which counters free radicals in the blood, and is thought to be therapeutic both for the cardio-vascular system and against cancers, specifically prostate cancer. These particular tablets are not from GM plants. But the second generation of genetic modification is directed at producing lycopene-enhanced tomatoes.

First generation genetic modification of the tomato (and other crops) used the technology of 'gene silencing'. As we have seen, a natural property of the plant was 'switched off', to delay or prevent ageing. Importantly, the technique involved was to identify the DNA sequence, and then either copy the same gene sequence or use an anti-sense or inverse sequence of the same gene, before inserting it into the tomato germ cell. The effect, similar to an immune response, is that the cell recognises its 'own' copied or anti-sense gene, and destroys the genetic material of that particular gene sequence, so 'silencing' or 'switching off' the gene. This is what is done for GM tomato purée. No non-tomato genetic material is involved. The modification involved does not introduce something alien to the organism, but switches off one of its normally occurring processes. By switching off the ethylene gene, for example, it is possible to make the unripe tomato fruit live 'forever'.

Second generation genetic modification enhances naturally occurring characteristics of the plant, such as lycopene, to create Nutrient Dense Foods (NDFs). Following from the analysis of the previous section, the European Union Fifth Framework for scientific funding of GM research has required that there are demonstrable health and nutritional benefits. The lycopene enhanced tomato is being developed as a new species to inhabit this particular socio-ecological environment. Other GM research is leading to the production of flavour enhanced foods. But, in order to enhance the naturally occurring properties of a plant, the techniques involve circumventing the normal 'immune-type' response to homologous genetic material, by the introduction of heterogenous genetic material from other plant species, such as capsicum or bacteria, such as yeast. The process of genetically engineering a lycopene-enhanced tomato leads both to an increased understanding of natural properties of plants, and to therapeutic and 'economically interesting' possibilities.

NDFs have a far greater potential than synthetic nutraseuticals like aspartame (Fine et al, Chapter 6, 1996), inasmuch as they involve general nutritional and aesthetic dimensions, and concern food rather than food additives. Consequently, the research involved encompasses a much broader range of sciences aside from molecular biology and plant physiology: human physiology to examine the best way of ingesting lycopene, epidemiology to relate cultural diets to health variations positive and negative, and food psychology to explore the aesthetics of the new food. Thus, tests have shown that lycopene is most readily absorbed when cooked in olive oil and eaten in the form of pizza toppings or sauces. The fact that what may have been found empirically to be 'good to eat' and 'good for you' has been given a scientific imprimatur via genetic modification centuries later, might provoke a wry smile. But then, genetic modification potentially could also bring about a further significant shift in human cuisine amplifying the effects of introducing tomato into Europe in the first place. If broadly extended to other nutritional properties across the spectrum of the food we eat, it could change the pattern of cultivation, especially when combined with new ways of achieving eco-sustainability to which I now turn

GM and the road to high-tech eco-sustainability

The argument was made above that advances in molecular biology are pervasive, now working their way through various domains of technology as well as leading to further understanding of fundamental organic processes. In the current debate, therefore, it is important to recognise that the hybridisation which has produced the ubiquitous cultivated natural species of plants and animals farmed today is now also being revolutionised by recombinant DNA technology. DNA markers are replacing bio-chemical enzyme or phenotypic markers as selection tools. There is something important here about the generative power of a new scientific paradigm, as a characteristic of human knowledge.

Seed manufacturers, producing new varieties of tomato (and of course many other plants and animals) are capable with the new technology not only of developing aesthetic variations in taste, colour, shape, size, but also disease and pest resistant varieties. The new technology has enabled precise targeting of desired traits of resistance in a way impossible before, and thereby already presents economically viable alternatives to the use of agro-chemicals. In so doing, the boundary between GM and non-GM is diminished, as both rely on the same science base and the same recombinant DNA technology. There are also various combinations between hybridisation and GM that will no doubt develop to blur the distinction further. This process may assist understanding of cross-species gene transfer and species stability. In whatever combination, however, technologies for the elimination of the use of agro-chemicals and development of new levels of nutrient density suggest a route to a high-tech eco-sustainability. The route is certainly different from, and maybe more realistic than, that offered by the 'nature fundamentalism' prescribed by the current 'organic' movement, with its insistence on supposedly more natural modes of cultivation ensconced in 'tradition'. To be sure, such a high-tech route to eco-sustainability also necessitates an appreciation of new interactions between cultivated and non-cultivated nature. But the new science is probably better placed to make that appreciation.


A photograph in the Guardian (21.8.99) shows anti-GM protesters pulling out GM rape. They are dressed as scientific monsters from outer space, to articulate the vision of the evil scientist behind Frankenstein foods. Of course, scientific understanding and new technologies have tremendous negative as well as positive potential. But its negative potential does not forcibly impel one into either anti-scientific clothing or nature fundamentalist politics. The advancement of the 'precautionary principle', if interpreted to mean that no action should be taken until all unintended consequences of human action are known, would have seriously reduced the human species' chances of survival. There are risks in GM technology, and by scientifically informed and consistent international regulatory regimes these need to be minimised to the full extent of current knowledge. By taking minimised risks, however, there are also manifest gains to be made, for cultivation and comprehension of nature, for nutritional and health benefits, and for new cultures and aesthetics of food. It has been argued above, that the trajectories of genetic modification, and the working through of molecular biology, are socially embedded, subject to different regulatory regimes and commercial, capitalist, imperatives. Rather than adopting an 'anti-science' or 'nature fundamentalist' stance, the shaping of these trajectories is more likely to be effective if the positive potentials are embraced together with the, social, economic and ecological imperatives of reducing inequality, eliminating hunger, creating sustainability.


1The EC Directive 90/220/EEC is more accurate in defining, for regulatory purposes, genetic modification as the alteration of an organism's genetic material 'in a way that does not occur naturally by mating'. (Article 2). For further discussion on diverse regulatory definitions of genetic modification see Schuch, W. and Poole, N. 1993.

2This article covers a small area of a much larger research project on the cultural and political economy of the tomato undertaken with my colleagues Huw Beynon and Steve Quilley (Harvey, Beynon, Quilley, forthcoming), at the ESRC Centre for Research in Innovation and Competition at the University of Manchester and UMIST. However, I take full responsibility for the views on genetic modification expressed here. The research on genetic modification is based on extensive interviewing of the scientists, the biotechnology companies, the tomato growers, the supermarkets and seed-manufacturers, involved in genetic modification, as well as with The Soil Association, Greenpeace, Friends of the Earth, Genewatch, and those opposed to it in the UK.

3Thus, Tesco's favoured eco-friendly tomato, a special hybrid, is called 'Nature's Choice', whilst Sainsbury advertises that 'if you're looking for a tomato that's naturally perfect, pick one up at Sainsbury's.' July 1999.

4It could be argued that the tomato is rather a special case of genetic modification, quite different from broad acre crops such as rape, soya, cotton, sugar beet. However, much tomato production is open-field; there are wild species closely related to it; much open field production is under an agro-chemical production regime; but above all it raises many of the same issues in principal as other GM crops. Greenpeace clearly thought so at one stage in preparing an unpublished report which viewed tomatoes as the Trojan horse of genetic modification (Mayer and Rutovitz, 1996).

5For a comparison with how pharmaceutical usages of recombinant DNA technology were also shaped by the markets in which their end-products became established see Green (1991).


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Copyright Sociological Research Online, 1999