The debate is actually hopelessly confused, and confusing. The data in the PNAS article is clear. Inefficient feed systems result in more greenhouse gases being produced during production than more intensive systems (essentially more belching and farting). And white meat (pigs and poultry) are better than red meat and milk in this regard.

But the assessment does not account for the costs of the other inputs of industrial farming, including fossil fuels used in feed production, housing, transport and so on. Traditional livestock systems are often very ‘low input’, with little fossil fuel dependency, and linked into markets not reliant on massively long supply chains.

Such systems make efficient use of marginal land and resources; as Tara Garnett puts it a ‘livestock on leftovers’ approach focused on adapting existing systems rather than the simple focus on efficiencies. The trouble with studies such as the PNAS one is that the results and conclusions depend crucially on what ‘the system’ is, and what is being compared with what. These choices are crucial and can inject fatal biases, or encourage wayward misinterpretations.

Simon Fairlie produced a brilliant book a few years back, Meat: a Benign Extravagance. It even got George Monbiot to change his views on meat eating. The book argues – with masses of data and careful argument – that meat production if done in an ecologically sensitive and humane manner is fine on a whole range of counts, and should not be discounted as a form of production and source of livelihood. It just depends on who produces it and how. The same applies in the great climate and environmental impact debate, a theme that is picked up in the book, and in a recent paper that questions many of the data assumptions used in FAO’s livestock climate assessments.

In the exchange of comments following the Economist article Mario Herrero distances himself from the claims made by the Economist, arguing that they never claimed that “we should get rid of pastoralism” (they didn’t!). Instead he argues that small-scale intensive systems are the best way forward, as part of a diversity of approaches.

This is all well and good, but how then can the extensive savannah grasslands of Africa be best used? This is not where intensive small-scale systems are likely to emerge. Should they be turned over for carbon sequestration as some argue, or wildlife, with people and their environmentally destructive animals forced off the range? What then happens to the many livelihoods of often very poor people who are dependent on livestock? And if livestock are not consuming the grass, fires or termites might resulting in less production and perhaps even larger emissions.

The problem with studies of this sort – and perhaps especially the media and policy commentary that follows – is the way that complex systems are simplified. First is the way the accounting is done, with often limited data and missing out key aspects. What is included in the model and how it is bounded makes a huge difference. In this case focusing only on food conversion efficiency gives a distorted picture of climate impacts of different livestock based production-marketing systems.

Second is the interpretation that focuses on the accounted for measure – in this case greenhouse gases – and excludes the complexity of the wider system. Any assessment of costs and benefits must look at the whole picture, including the array of opportunity costs and trade-offs, and so crucially must involve the people concerned who know these best.

Third is the way uncertainties are dealt with, often put to one side (or in very long appendices of supplementary data). In the case of aggregate global pictures across all livestock systems, uncertainties can be massive. Inadequate data plagues agricultural policymaking, and particularly for extensive livestock. Add to that the uncertainties associated with climate change predictions and the data problems are compounded.

And fourth is the way alternatives are defined as part of policy narratives that are developed through such modelling efforts. By defining (narrowly) a problem, a solution (again narrow) is defined. Too often dramatic alternatives to the status quo are recommended, without thinking about the consequences.

Pastoralism is a way of life adapted to dry non-equiibrium rangelands, and is a massive contributor to livelihoods and economies, as well as providing a route to land management. Our book, Pastoralism and Development in Africa, highlighted through many case studies the way pastoralism contributes to development in the Greater Horn of Africa. A similar case could be made for the livestock dependent areas of Zimbabwe, as I and many others have long argued.

Surely the most appropriate response is to seek out more climate-compatible forms of livestock development, based on existing systems, and working with people and their animals, rather than seeking a dramatic transformation that would result in increased poverty and growing inequality in already poor areas of the world. The models may help think through the options, but they are no replacement for engaging with the realities on the ground.

This post was written by Ian Scoones and originally appeared on Zimbabweland