Harold Brookfield has written an excellent exploration of the physical and intellectual requirements, as well as the principles and practices, that promote and maintain agricultural diversity. To do so, Brookfield uses various analyses--scientific, cultural, and historical--to interpret a compilation of research and source material collected over 50 years. Case studies from a number of other scientists, as well as himself, produces a mosaic of thought-provoking oversights that leaves one wondering: Why was this information not common knowledge before now? It is a question that he answers early on as he journeys through time from the late 19th century into the 20th century and every continent. Along the way, readers are introduced to similarities and differences in the way cultures view and use land, and whether agrodiversity is valued or not, particularly by policy-decision-makers.

The history of agrodiversity is fraught with conflict. In my lifetime, the farther our policy-makers have been removed from their family roots on farms, the farther their minds are removed from the land and its life, above and below the surface of the soil -- with one exception, the extraction of mineral, metal and chemical resources.

In her book, God of Small Things, Arundhati Roy utters a simple, but powerful refrain: "I think the kind of landscape that you [grow] up in...lives in you." She could have been talking about one cause for the loss of agrodiversity, which has been accompanied by the forced removal of those who loved the land for what they could produce on it to be replaced by those who want the land for what they can take from it. In India alone, more than 50 million farmers were removed from their land since 1948 so political and corporate interests could build more than 3000 dams. Dams are not just construction projects, they are open-pit mining projects, whose extracted soils are carried away without oversight to be processed for what they contain.

Globally, the Green Revolution in the 1980s and continuing, was orchestrated by agribusiness companies in developed countries, most notably the United States, to sell more petrochemicals for monoculture crops. As a result, countless more farmers were driven into urban slums or into internecine wars and death. It's no wonder that hunger and misery remain as human plagues into the 21st century. This book should probably be read in conjunction with Jared Diamond's, The Third Chimpaneze, to fully appreciate the human factor in the devolution of agriculture.

Brookfield reveals these scars in a scholarly and incisive, though highly readable, style, without always identifying the political choices made as I have above. Yet, throughout the book, you get the idea that he wonders what might have been had different choices been made. What does the future hold for biodiversity on farms, given the advances in science, the vagaries of politics, and the rising tide of farmer advocacy as another, younger generation of farmers begins to push forward models of regenerative agriculture, which are biodiverse and less intrusive?

This new generation is discovering, too, some old ways of whole farm design. The comparisons between the permaculture designs of Bill Mollison and David Holmgren can be seen in the schematic structure of the tapades of Fouta Djallon in Guinea, West Africa, who do it better on even less hospitable earth than most. Brookfield's review of the tapades, their history, and the process of manufacturing soil by the women resident in them is a welcome addition to an English-speaking audience. In fact, the entire chapter on soil and plant relationships is an excellent summary on what we have come to know.

Still, the joy in this book for me is the many globally unrevealed innovations by farmers whose families or societies have maintained their linkage to the land. One of these is the Bemba in northwestern Zambia who created crop circles, referred to locally as citemene and the contemporary science that explains their reasoning for doing so. It is these innovations that give some hope to the sustainability of biodiversity in agriculture and on the planet.

The only glaring weakness I find is the lack of sketches or graphic images of the many examples about which Brookfield writes. These might have not only illuminated the examples, but made clear to proponents in the regenerative agriculture movement that certain ideas they believe to be recent innovations by their contemporary gurus are not. Nonetheless, I am thankful for this work. Anyone interested in biodiversity and food production can gain a more detailed understanding about this subject, so put this book near the top of your must-read list.