The readers of this journal will already be well aware of the parlous state of biodiversity. Nature’s Matrix makes a very reasonable argument that the biodiversity crisis cannot be separated from the production of food and the political unrest that characterizes much of the tropical world that is richest in biodiversity. It highlights the ignorance of fundamental ecosystem processes and the role that humans play in determining their productivity, and argues that accepting the current dominant political ideologies as universal and sacrosanct is highly arrogant and hardly supported by the evidence. The authors' solution: recognize the small farmers as the most powerful allies in the effort to conserve biodiversity. They draw on evidence, mostly from Latin America, in support of this argument, drawing on the familiar examples of shade coffee in Central America, cacao in Brazil, and rice cultivation in parts of Asia to make the point that it is far better to manage agro-ecosystems to prevent problems from arising than depend on agronomists to solve problems after they have appeared. ‘Agronomists seek to solve problems, agro-ecologists seek to prevent them,’ a point the authors—agro-ecologists all—seek to demonstrate with this book.

While much of the book seems to bring back the now-discredited so-called noble savage approach, it makes the reasonable case that a social movement for food sovereignty will be based on production systems that will conserve biodiversity and build on the functioning of the local ecosystems. Fair enough, but what about the many parts of the tropics where the land is being abused. Haiti is only the most dramatic example but many others could be quoted. The book applauds the ‘fundamental right of farmers to land, water, seeds and other means of production,’ yet says little about the many conflicts over these key inputs, especially as populations increase and large corporate farmers become more attractive to those providing food to the growing urban consumers. While it is reasonable to support social movements for food sovereignty, ignoring the impacts of the wealthy is likely to make such support more difficult rather than easier.

A more important concern for the readers of this journal is that the authors repeatedly cite extinction as a normal process, and consider the charismatic megafauna as doomed to probable extinction, despite all the efforts seeking to avoid such a fate. They want us to be more concerned about bacteria and other soil micro-organisms (which undoubtedly do deserve more attention), while downplaying the mammals that ‘happen to look more or less like us.’ Bats, mole rats, sperm whales, and indeed most other mammals hardly fit this description, but this is a minor issue compared to some of the fundamental ecological arguments the book makes. For example, to argue that ‘species diversity tends to decrease as the intensity of management of the ecosystem increases’ only holds for agricultural lands; many protected areas being managed to maintain high biodiversity require intensive effort to achieve their goal. Perhaps recognizing those seeking to conserve biodiversity as ‘resource managers’ rather than ‘conservation practitioners’ would give the authors a broader perspective. Their repeated argument that stopping extinctions is bad conservation policy will not convince many of us, especially when so many extinctions are the result of human actions that could be avoided. The current rate of extinction is widely agreed to be about 100 to 1,000 times the normal background rate, but this fairly fundamental figure is not cited or refuted in this book, which instead argues that agro-ecosystems are ‘critical repositories of biodiversity.’ While this may well hold for many species, it can hardly be accepted as a generality for biodiversity (which is never actually defined in the book). Certainly well-managed and diverse agricultural landscapes can support numerous species, and do so in many parts of the tropics. Thus the argument of maintaining diversity in the agricultural landscape is well taken and deserving of support. But this is only part of the story, as over half of the planet’s land is not used for agriculture and needs to be managed better to conserve biodiversity. Further, the Millennium Ecosystem Assessment identified invasive (non-native) species as one of the five major drivers of ecosystem degradation, yet this book seems to welcome these additions to ecosystems (considering them as part of ‘migration rates’) as a way of replacing the species that have unfortunately been driven to extinction.

Bottom line: the book argues that ‘a serious conservation programme should focus on the type of agriculture practiced within the matrix, rather than on what happens solely in the fragments of natural habitat.’ But this either–or argument makes the choice too stark. Rather, we need to manage the matrix as a whole, giving appropriate attention to all parts of the landscape and working closely with the people living on the land, with some of us devoting particular attention to those areas richest in biodiversity while others seek to manage their agricultural lands to contribute to the overall social goal of maintaining the living wealth of our planet.