Why Diversity on the Dinner Plate Is Becoming an Endangered Species

Americans once grew and ate 15,000 varieties of apple, each different in name, taste and texture. What's left today are about 10 percent of those varieties, the rest consigned to a fate people seldom associate with food.

"The idea of endangered species is pretty well established; people understand that a particular salamander might be endangered," said Jenny Trotter, who heads the biodiversity programs at Slow Food USA. But endangered apples -- that's an idea few eaters recognize even as biologists sound a growing alarm about the rapid loss of genetic biodiversity in the global food supply.

Seventy-five percent of the world's food now comes from seven crops: wheat, rice, corn, potato, barley, cassava and sorghum. And it increasingly comes from narrow strains of those crops selected for efficiency in producing the most food on the smallest patch of land in the least amount of time.

Fine diners have come to recognize an alternative in "heirloom" tomatoes, a term denoting generations of conservation by farmers who can trace the origin of a unique seed's selected breeding by as much as centuries.

The same concept, though rarely appearing on farms -- and even more rarely marketed on menus -- applies to grains and lettuces and pears. Even cows. But today, 99 percent of turkeys eaten in America come from a single breed, the Broad-Breasted White. More than 80 percent of dairy cows are Holsteins and 75 percent of pigs come from just three breeds.

In the winnowing of efficiency, "heirloom" and "heritage" landraces are disappearing, taking with them their diverse genes and, scientists argue, man's best chances for survival. Please recall, they all suggest, the Irish potato famine. More recent epidemics have threatened entire regional industries as well as grocery-store produce: the billion-dollar 1970 corn blight, the 1984 Florida citrus canker, and the wheat stem rust, which may yet do its worst damage.

Blights, viruses and insects evolve over time to counter agricultural repellants, meaning crops will have to evolve over time, too. And today, as climate change promises to target agriculture, more than ever farmers may need to rely on the untapped genes of crops that grow on little water or in high heat, or livestock that can forage on grass should the price of the corn we feed them go up from competition with biofuels.

We've also come to rely on some food sources -- that Broad-Breasted White turkey, for example -- that can no longer naturally reproduce. Which seems biologically troubling, right?

"It's a question that needs to be asked, and if our entire food system is based on that resource, that becomes a question we can no longer ask," said Phil Sponenberg, a professor of pathology and genetics at Virginia Tech and an adviser to the American Livestock Breeds Conservancy. "For turkey production, if all we had were artificially inseminated industrial turkeys, and all of a sudden, if we want to say, 'Is this how we should be raising turkeys?' it becomes increasingly difficult to ask that question."

Alternative ways of raising turkeys, in other words, would no longer be an option.

"I just like the idea of all the options being on the table," Sponenberg said.

His suggestion for keeping them there is laughably simple.

"We have to eat them to save them,'" said Jennifer Kendall, the ALBC's manager of marketing and communications.

In an era when many problems -- deforestation, climate change, water shortages -- have been caused by human over-consumption, here is a problem of under-consumption. Biodiversity is disappearing precisely because people no longer consume it, and if we would just eat endangered crops and livestock now, restoring their role in the food supply, we could save them from extinction.