New Archaeology of Lost Crops Shows the Reign of Corn Wasn't Inevitable

The old, epic story of agriculture in North America had two heroes, long sung and much venerated. One was human ingenuity. The other was corn.

That story went something like this. On this continent, agriculture—and therefore civilization—was born in Mesoamerica, where corn happened to be abundant. The more advanced people there began cultivating this knobbly little plant and passed their knowledge north, to people in more temperate climes. When Europeans arrived, corn ruled the fields, a staple crop, just like wheat across the ocean. If the Middle East’s Fertile Crescent was agriculture’s origin point for Europe, Mexico was agriculture’s origin point here. This very human innovation had unspooled in the same rare way in these two places. Superior men tamed nature and taught other superior men to follow.

Part of this story is true. The first ear of corn—although calling it corn might be a stretch—likely grew somewhere in the highlands of Central Mexico, as far back as 10,000 or so years ago. The oldest known bits of recognizable corn, a set of four cobs each smaller than a pinky finger, are some thousands of years younger than that. They were uncovered in Oaxaca, in 1966, and that site, cuna del maiz, the “cradle of corn,” is in concept a landmark of human advancement on Earth. In appearance, like many archaeological sites, it is unimpressive, a cave so shallow that even the designation “cave” is questionable. But sometimes a whole history is preserved by chance on a dry cave floor. Sometimes a handful of seeds can help confirm a theory about the dawn of agriculture, or help unravel it.

Humans have been living in the valley of Oaxaca for ages; now the main road passes a boomlet of mezcalerias, flat fields of corn, and an antique cliffside etching of a cactus. Some nearby caves, too, have traces of ancient wall paintings—a jaguar, two stick figures, and la paloma, “the dove.” When, starting in 1964, the archaeologist Kent Flannery came to this valley looking for a place to dig, he examined more than 60 of these caves, tested 10 or so, and eventually focused his work on just two. And in one of those, he found some notably old corn cobs. Today, that cave is contained in a biological preserve where council members of the nearest town patrol the grounds and, from time to time, guide visitors up the ridge. Mostly they show off the ancient paintings, in vaulted caves with views that stretch for miles.

The corn cave, which is no taller or roomier than a modest corner office, likely served as a storeroom or shelter for nomadic peoples, who left behind bones and plant detritus as far back as 10,000 years ago. Amid the remains of deer, rabbit, mud turtle, mesquite, pine nuts, squash, and prickly pear, Flannery and his crew found those four scant specimens of corn. These days, the cobs are usually stored in Mexico City’s fabulous Museo Nacional de Antropología, but the winter I visited they happened to be on display in Oaxaca’s cultural museum. They, too, are not much to look at—skinny nubbins of plant, black and cragged with empty spaces where kernels once grew. Really, they’re hardly corn. And that gap, the distance between these hardly-corns and the flush, fleshy ears that sustain nations, is where the old story of agriculture’s origins starts to break down.

The development of agriculture, the Marxist archaeologist V. Gordon Childe declared in 1935, was an event akin to the Industrial Revolution—a discovery so disruptive that it spread like the shocks of an earthquake, transforming everything in its path. Childe’s work on what he termed “the Neolithic Revolution” focused on just one site of innovation in the Near East, the famous Fertile Crescent, but over time archaeologists posited similar epicenters in the Yangtze River valley of East Asia and in Mesoamerica. From that third point of origin, corn is supposed to have converted naive, nomadic hunter-gatherers into rooted, enlightened farmers throughout the continent, all the way up into the northern plains.

This long-held narrative now seems to be incomplete, at best. After all, corn took its sweet time fomenting that revolution—thousands of years to transform from scraggly specimens like the ones found in Oaxaca to full-on corn, thousands more to migrate up from Mesoamerica, and still more to adapt to the growing season at higher latitudes. In the rolling fields of the Midwest, the breadbasket of the United States, maize-based agriculture took over only with Mississippian culture, which began just one short millennium ago.

Over the past few decades, a small group of archaeologists have turned up evidence that supports a different timeline, which begins much, much earlier. Plant domestication in North America has no single center, they have discovered. In the land that’s now the U.S., domestication was not an import from farther south; it emerged all on its own. Before Mexico’s corn ever reached this far north, Indigenous people had already domesticated squash, sunflowers, and a suite of plants now known, dismissively, as knotweed, sumpweed, little barley, maygrass, and pitseed goosefoot. Together, these spindly grasses formed a food system unique to the American landscape. They are North America’s lost crops.