Synthetic biology is an astonishing field. Its scientific ambition is breathtaking. According to the Global Network of Science Academies, it involves no less than ‘the deliberate design and construction of customized biological and biochemical systems to perform new or improved functions’. Synthetic biologists hope to create a new industry by treating DNA as if it was computer software.   Writing in Nature, Daniel Gibson observed ‘A biological cell is much like a computer – the genome can be thought of as the software that encodes the cell’s instructions, and the cellular machinery as the hardware that interprets and runs the software’. Scientists can act as biological ‘software engineers’, programming new biological ‘operating systems’ into cells. That is quite an ambition.

Synthetic biology  has significant implications for conservation, from the speculative world of de-extinction (whether the cloning of mammoth or the summer blockbuster of Jurassic World) to the idea of fighting wildlife disease (such as white-nose disease in wild bats or chytridiomycosis in amphibians), or addressing human impacts on land and ocean. It has the potential to transform the production of food, fibre and oils, the flows of materials through the urban-industrial system, and human ecological interactions. It is likely to be a seriously disruptive innovation in many fields, from medicine or agriculture to energy supply.

In a world of Promethean environmentalism, synthetic biology offers perhaps the perfect combination of possibility and risk. On the one hand it offers solutions to global sustainability challenges in food, water and energy. On the other hand, it channels environmentalist fears about the scope of corporate control of genetic knowledge and the development, patenting and release of novel organisms.

But synthetic biology is not just another technology. It has profound implications for relations between humanity and non-human nature. As Neil Smith observes, it extends human artifice – and corporate interests – right down to the level of the genome.   So a key question is, how should we think about it?

One way is to consider synthetic biology within the frame of what Marxists call the ‘metabolic rift’. This concept builds on Karl Marx’s analysis of a rupture in the metabolic relations between humans and the rest of nature caused by capitalist production. Marx was influenced by Justus von Liebig’s application of the concept of metabolism to agriculture in 1842. The term ‘metabolic rift’ was coined by John Bellamy Foster, in a paper in the American Journal of Sociology in 1999 and his book Marx’s Ecology the following year. The concept is much debated.

In Foster’s account, Marx believed that the intensification of agriculture in the nineteenth century caused an ‘irreparable rift’ in ‘social-ecological metabolism’ (Foster 1999, p.380). To Marx, capitalist agriculture robbed soil as well as worker, causing the decline of soil fertility due to the loss of local closed nutrient cycling. There is debate as to when capitalism transformed the nature of agriculture’s metabolism (sixteenth century ‘high farming’ doing so long before Leibig and industrialism). But the result was the same: an ‘antagonistic division between town and country’, a metabolic rift, persisted and grew.

The immediate consequences of the metabolic rift in agriculture (in terms of declining crop yields) were addressed by the application of chemistry to the industrial production of synthesised phosphates, and in C20th, by nitrate fertiliser. But the metabolic rift involved in wider capitalism, industrialism, and modernity progressively deepened, from the exploitation of land, ocean, and atmosphere, to modernity’s growing dependence on fossil carbon: the legacy of past ecosystems mined to power the present.

In the context of the concept of metabolic rift, what kind of a shift in human relations with nature does synthetic biology represent? It may be a difference of degree, not kind, but it is a profound one.

Until very recently, human appropriation of nature has relied on the use and manipulation of existing species, ecosystems and environmental processes. Hunters still kill and gather. Farmers store seed, plant and tend crops, and manage soil fertility. In industrial agriculture, the loss of nutrients in crops is compensated by fertilizer (historically guano or even phosphorous-rich coprolites from the fields around the village where I live, nowadays by artificial fertilizer), while wider ecological interactions with crops are suppressed with the endless armoury of synthesized pesticides, from DDT to the apparently disastrous Neonicotinoids. Even crop breeding has traditionally involved working with crop biology and field ecology to select desired strains.

While the history of human uses of nature is one of escalating intervention and attempts at control, synthetic biology is nonetheless different. Synthetic biologists may be thought of as ‘writing software’, but it is software that does more than reprogramme a machine. It can create its own hardware, in a self-supporting and evolving process. Once DNA is reprogrammed, a new biological system is potentially capable of running itself.

If new organisms are contained within laboratories or closed industrial facilities, they may remain under some measure of control (and be dependent on continuous human inputs: labour, Marx might say, or nutrients). If they are released (and terms like ’the field’ or ‘the wild’ are decreasingly useful to describe this critical transition) and breed and evolve, the potential for changes to nature is essentially unbounded. The recent International Summit on Human Gene Editing in Washington DC 2015 expressed caution about genetic alterations to the human germ line (which are carried by all of the cells of subsequent generations). Such genetic alterations ‘would be difficult to remove and would not remain within any single community or country’. This is even more true of novel organisms in the myriad complexity of unbounded ecosystems.

Synthetic biology marks a new phase in the relations between humans and the rest of nature. For the first time, humans get to write the programmes for living nature, not simply appropriate, control and crudely adapt the bits they want. It is in this that synthetic biology involves a new and profound dimension of the metabolic rift. Human enterprise (and capitalism) can now ‘bore into and transform the core of specific life forms’ (as Neil Smith puts it) in new ways and to new depths. It brings power over the genetic structure of life itself, and places this power within the realm of industrial production.

Synthetic biology allows nature to be reprogrammed, not just managed. Moreover, many of the key players in this programming are for-profit organizations. Synthetic biology places nature more firmly under the control of capital, opening a new realm of opportunities for the patenting of living organisms. Many future synthetic natures will be patented, self-reproducing industrial elements designed to yielding profit for shareholders (even as, or even if, they feed and clothe and power the rest of us).

Synthetic biology needs to be understood as a socio-technical system, and as a socio-economic project. It will create winners (e.g. the corporations that sell new biological devices), and losers (such as the farmers of artemisinin, vanilla or heroin, out-competed by chemically identical synthetic compounds cultured in a laboratory). The distribution of benefits and costs will be critical to the social acceptance of the technology.

Synthetic biology offers obvious opportunities for positive change, for conservationists and many others. But there are also risks, and challenging questions around how to govern this technology and those who manage it (be it in a public research institute, a corporate factory or a neighbourhood garage; in California or a ‘pariah state’).

The original metabolic rift also brought an immensely complex legacy: wheat yields at ten tons per acre and the end of mass famine through agricultural intensification, but also the devastation of ecosystems by that same industrial agriculture, the depletion of natural resources and the growth of polluting industrialism.

What might the pragmatic environmentalist have said to Marx, or Liebig, in the 1860s if they could have seen the future of industrial agriculture? Perhaps just four things. First, the changes are likely to be dramatic, Second, the effects of change will be complicated. Third, there will be losers. Fourth, it matters who controls this technology.   Exactly the same goes for synthetic biology today.

(My thanks to Elia Apostolopoulou, Chris Sandbrook and Emily Adams for their comments on this piece: they bear no responsibility for errors!)