Wednesday, February 24, 2010

Evolution and Food - The Red Queen Principle

“Well, in our country,” said Alice, still panting a little, “you’d generally get to somewhere else – if you ran very fast for a long time as we’ve been doing.”

“A slow sort of country!” said the Queen. “Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!”

“I’d rather not try, please!” said Alice. “I’m quite content to stay here – only I am so hot and thirsty!”

~ Lewis Carroll, Through the Looking-Glass

Animal, Vegetable, Miracle: A Year of Food Life is Barbara Kingsolver’s biting, articulate, persuasive bill of particulars against agribusiness for what she finds wrong about how most of the food is produced, distributed, and marketed in this country and now throughout much of the world. The agribusiness villains of the piece are damned for, among other sins, their concentrated animal feeding operations for which the adjective “cruel” is too mild, and their genetic modification of our food plants, a pernicious process protected by a legal framework that turns reason on its head.

I just finished reading this nonfiction volume (published in 2007) and, though Kingsolver ranks among my favorite novelists, particularly for the novels she wrote early in her career like The Bean Trees and Pigs in Heaven, and I have been moved by those novels, only this book of hers has caused me to rethink aspects of how I live my life. Hard to give a writer higher praise, I think. And there’s some interesting and important science here, too (or else how could I justify putting this post in this blog).

(I know I'm coming late to this book and this subject. If some venting on this subject isn’t of interest – which occurs both in the book and in the rest of this post – my apologies. Hope to see you next time.)

Animal, Vegetable, Miracle is the account of a year in which Kingsolver, her husband Steven Hopp (who contributes a number of background pieces to the book), and daughters Camille (who contributes recipes and stories of food) and Lily seek to free themselves from the reach of agribusiness by growing as much of their food – animal and plant – as possible on their small farm in Virginia, and by buying from farmers in their local area. The struggles and triumphs of that year are set against descriptions of the devastating impact of agribusiness on our food supply, our health, the nation’s small farmers, and our local communities. Theirs is an inspiring saga (that of agribusiness, not so much) and, frankly, there’s hope that a change in attitude is taking hold in the general population that will, in turn, change what we eat for the better.

Kingsolver’s message is summed up by Tod Murphy, the owner of the Farmers Diner. (At the time the book was written, the diner was in Barre, Vermont, but the operation has expanded and been relocated to Quechee and Middlebury, Vermont.) The Farmers Diner is of its local community – serving food made from local produce and meat. Murphy’s motto is:
Think Locally, Act Neighborly

In other words, a key to fixing what’s wrong with our food supply is to shift our focus to what’s grown in our extended neighborhoods and, short of raising our own food (well, perhaps trying to do a bit of that), this means buying as much food grown locally as we can, produce grown for taste not for its ability to endure many days and thousands of miles in transit. Our charge is to let local grocery stores know our preferences for fresh, local produce, shift food dollars to farmers’ markets, find alternatives to processed foods.

Why is changing our food habits so tough to do? Yes, we have multi-billion dollar conglomerates aligned against us and our best interest. But, more intriguing to me, is Kingsolver’s assertion that we are victims of evolution and that evolution helps explain why junk food accounts for about a third of our calories. She writes,

. . . humans have a built-in weakness for fats and sugar. We evolved in lean environments where it was a big plus for survival to gorge on calorie-dense foods whenever we found them. Whether or not they understand the biology, food marketers know the weakness and have exploited it without mercy. (p. 15)

Evolution plays other critical roles in the mess that we’ve created in our food supply. For example, the arms race between insect pests who attack food plants and the scientists creating ever stronger pesticides that enter the world’s food chain is one that the powerful evolutionary engine is bound to win. Hopp cites the following damning statistics: In 1948, farmers applied 50 million pounds of pesticides and suffered a 7% loss rate of their crops. In 2000, a billion (that’s a billion with a “b”) pounds of pesticides were applied and the loss rate was . . . 13%. His solution: “Organic agriculture, which allows insect predator populations to retain a healthy presence in our fields, breaks the cycle.” (p. 165) [Later edit: Hopp's data apply to U.S. farmers.]

Even more troubling to me is the loss of diversity in our crop plants. Kingsolver, who did graduate work in evolutionary biology, lays it out clearly. This is where the Red Queen principle spells trouble. A descriptive label drawn from Through the Looking-Glass, it was first used by evolutionary biologist Lee Van Valen to describe the constant evolutionary point-counterpoint that marks the relationship between predator and prey in which the former evolves to gain a small advantage only to have it countered shortly by a change in the latter – a never-ending process (well, we hope it’s never-ending), one involving running as fast as a species can in order to stay alive and propagating in the same place. Our crop plants and disease are co-evolving, locked in a struggle for survival, but the loss of diversity in the former takes potentially vital genetic variety out of the plant arsenal, leaving plants at risk of being unable to respond to the newest development in the disease community. Kingsolver points to the Irish potato famine as but one example of how the danger may play out. Today, agribusiness has ensured that just a few varieties of corn and soybeans are the source for many of our calories. As she puts it,
Our addiction to just two crops has made us the fattest people who’ve ever lived, dining just a few pathogens away from famine. (p. 54)

How much of change this book will make in my food habits is an open question. There are a few small signs that something’s stirring, but only time will tell. A couple of days ago the seductive smell of baking bread, made from scratch, drifted through the house for the first time in probably 15 years. As I waited for it to be done, I ate slices of Rome apples (admittedly, not an adventurous choice) grown in an orchard some 117 miles up the road, and, later, I made a meat loaf for dinner using free range turkey from a farm in the same direction up that road. It’s a beginning.

Oh, of course it’s particularly hard to start down a path like this in late February. Fresh, local produce? Our local farmers’ markets wont really get going for roughly another couple of months. And I don’t have a freezer stocked with produce from the past summer. Kingsolver speaks directly to me in this situation:
Eating locally in winter is easy. But the time to think about that would be in August. (p. 309)

A grand book (with a useful website).

Postscript [added later]

A current Wired magazine article highlights the importance of maintaining genetic variety among our crop plants, telling the dramatic story of the fight against the Ug99 stem rust fungus that has devastated wheat crops in Africa, moved into the Middle East, and may have set its sights on China and India. (Red Menace: Stop the Ug99 Fungus Before Its Spores Bring Starvation, by Brendan I. Koerner, Wired, March 2010). In a great deal of the wheat raised worldwide, the line of defense against stem rust consists of the Sr31 gene, bred into wheat from rye during the Green Revolution in the latter half of the 20th century. Now, with the emergence of the Ug99 pathogen (discovered in Uganda in 1999), this line of defense has been breached and wheat production worldwide is threatened. Too many eggs in one basket, it appears. It is fascinating to read of scientists scouring the world for wheat varieties that can be tested for resistance to Ug99, to the point of raiding a collection of seeds gathered during the 1930s from wild wheat varieties (yes, there is a reason to encourage the gathering and planting of seeds from heirloom varieties of plants). The hope now? Diamondbird wheat is proving resilient, able to contain stem rust, and, in contrast to the wheat strain with Sr31, this wheat has an array of minor genes manning its defenses – apparently a better tactic than the one that scientists previously relied on. Altogether, a compelling argument to stem the mounting loss of genetic variety in our crop plants that apparently has accompanied U.S. food policy over the last half century.

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