The park system is the prevailing model for biodiversity protection in the world - think Teddy R. and the US National Park Service; think Tanzania's Selous National Park, the biggest in the world. Armed guards, strict rules, "nature here, humans there". Biologists have long recognized that local extinctions were common, even in these big, dynamic parks, so "corridors" were the rage a few years ago, little pathways that would connect two "natural" areas to each other to allow migration (the solution to local extinction) - bridges over busy highways, for example. Most ecologists have found this approach hasn't worked.
Using an array of different disciplinary perspectives (biology, history, politics, anthropology), Perfecto et al. propose a "matrix" model of biodiversity protection that recognizes humans as potential stewards of the environment right where they live and work. Conservationists, they argue, have been blind to the political realities that drive extinction in the most sensitive regions, regions that happen to be in the poorest areas of the world. They focus their attention on agriculture, which has been such a destructive force in places like Brazilian Amazon. But they draw an important distinction between the Green Revolution-style industrial system usually encouraged by the global economic powers and the farming practiced by smallholders around the world. The latter, they argue, actually contribute to this matrix of biodiversity by showing more care for the land and thus conservationists should support and work closely with rural social movements that advocate for them.
The book cites two large case studies from Latin America from coffee farms in Central America and cocoa farms in Brazil. In both cases, the authors found a rich diversity of species living in and migrating through the farms. These farms practiced traditional and/or sustainable methods that involved the use of naturally occurring shade trees. Examples of maize farming in Mexico and wetland protection via rice fields in Southeast Asia are also provided. The authors make a well-developed argument that supporting such farms should be central to any conservation plan, especially in the developing world.
One minor criticism I have is the authors' somewhat incongruous choice of cash crop farms as a case study in arguing for food sovereignty. The methods practiced by these farmers is admirable, but they're still at the whim of global markets to a large extent. Farms provisioning food for local markets should play a bigger role in any discussion of food sovereignty. Nevertheless, the findings are hopeful and paradigm-rattling and will likely make conservationists and rural development practitioners rethink their methods.