Once Mexico Had a Wealth of Corn; Now It’s Left With a Genetically Boring Monocrop

This lack of diversity does not bode well for food sustainability and economics in light of climate change

corn
Photo: Campbell, Teri/the food passionates/Corbis

Corn was first domesticated in Mexico and quickly spread throughout the Americas, beginning in about 2,500 B.C. Over the centuries, around 20,000 or more different varieties emerged as ears of corn were transported around the world.

That diversity, however, is now on a steep decline. According to a recent study conducted by University of California, Davis, researchers, Mexico's corn varieties are disappearing much more quickly than originally assumed. This is a problem, the researchers explained in a release, because "genetic diversity is the basic ingredient for crops to respond to environmental threats ranging from pests to climate change.”

To arriving at these findings, the team analyzed 38 case studies that were conducted over the past 15 years and concerned corn diversity at various sites across Mexico. While past experts have found that corn diversity in Mexico is on the upswing, this new study reveals just the opposite: it is quickly declining, to the point that " widespread genetic erosion" is occurring on farms across Mexico, the researchers report. 

Corn isn't the only food that's suffering from precipitously declining diversity, either. And when plants and animals have only a limited arsenal of genes to work with, one blight or drought could easily wipe out the entire lot. With major environmental changes predicted to be on the way in the near future, those vulnerabilities might translate into real-world impacts, in the form of food shortages or price spikes.

Plus, diversity makes eating fun. Without our love of varied foods, we probably would be sticking more closely to a yawn-inducing but easy diet of bland staples such as boiled potatoes, iceberg lettuce and baked chicken. 

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