Georgina Mace CBE, FRS, Professor of Conservation Science at Imperial College, London, has raised fundamental questions about the nature of the science of sustainability in a recent online article. Here we probe her thinking and insights about the work we should be doing to understand how we can move toward sustainability.

Georgina, you are best known in IUCN circles as a population biologist for your scientific work underpinning the criteria for the classification of species’ status in the Red List, the Union’s most famous product. Now, in your capacity as an Academic Editor of PLoS Biology, the open-access online journal, you have published contrasting articles about the prospects for human beings in the biosphere (Burger et al. 2012 and Matthews and Bolz 2012) and contributed an editorial and podcast (http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001343) reviewing the articles and drawing attention to the shortcomings of sustainability science as currently practised. Thanks for agreeing to answer some questions from SULiNews.

Can you summarize the contrasting positions? Are the differences about the timing of our reaching ecological limits or something deeper?

I think these differences are more fundamental, they are not just about timing. The core issue in these papers is a disagreement between researchers about how likely it is that we humans will be able to work our way out of the problems caused by resource limitation through innovative new tools, products and practices. This is not a new discussion – it has been replayed many times, including the debate over the Club of Rome report that led to the ‘Limits to Growth’ and all that followed from that. The specific issues raised in these papers were over apparently well managed and sustainable systems (one a fishery, one a city) that had demonstrable impacts elsewhere that were not being accounted for. The authors (Burger et al. 2012) scale up those case studies to make the argument that at global scale, increasing use of resources has to confront certain limits that are unavoidable. The counter-argument (Matthews and Bolz) is there are many examples in history where cultural ingenuity and technological innovation have avoided such limits, and that the same will apply in the future.

What has led you, or PLoS Biology, to embrace these wider horizons? Why are these questions important for scientists to think about?

PLoS Biology
is an online, open-access, broadly-based biology journal. It has a very high impact factor and is selective about what is published in the journal to ensure high interest and relevance. However, the journal is also part of an open access movement that is based on the premise that societally relevant science should be available to everyone, at no cost to the reader. The journal also has different structures and article types to stimulate communities, encourage debate and reach out from science to wider audiences. The Burger et al. paper came to us as an Essay, one of these more open-ended forms, and during the review process it became clear that there was an interesting and potentially very relevant debate here, especially as we were in the run-up to Rio+20. There are few more interesting or engaging questions for scientists to think about – and it is clear from the reactions to these articles that the debate around limits to sustainability is still a lively one.

The relative failure of Rio+20 at the political level and the attacks on the international consensus on climate change suggests that policy-makers are less inclined than they were 20 years ago to listen to scientific advice. Do you think that we, the scientific community, are going wrong and if so is it because we produce too much doom and gloom?

I think doom and gloom can be off-putting for policy-makers. But I take my role as a scientist to be to tell things the way they are, and if that is bad news, then so be it. What we need to do more and to do better is to present to policy-makers the alternative ways of addressing such problems. We need to be solution-focussed, not just the purveyors of bad news. I think that scientists who bring a series of policy-relevant (not policy-prescriptive) solutions are taking the right approach.

You suggest that sustainability science is lacking an ecological dimension or, to put it another way, that bits of green technology are not properly connected up. What kind of research or initiative could begin to remedy this?

The necessary sciences cut across traditional boundaries – for example between resource economists and conservation biologists, or between social, physical and biological scientists. Development scientists and political economists are necessary, but not sufficient, for sustainability. However these are hard problems, and initiatives based at the interfaces often lack the necessary skills and knowledge. I think we need more well-resourced, multidisciplinary projects, designed to provide options for integrated solutions across the widest range of resources and needs that people have in particular places.

You say that it is hard to capture how systems work and to devise models. Are there any protocols which would ensure that models of complex systems are more holistic and less “pick and choose”?

There are some new approaches to these complex issues from complexity science. The approach is to clear away the complex aspects that do not contribute to addressing the issue. Modelling approaches such as agent-based models and network models have potential to help a lot. But I think there is a fair way to go.