Domestication of plants

The movement took place as a result of a population explosion and food shortages.

Five thousand years ago, the American continent went through a revolution similar to the one experienced seven thousand years earlier by Europe. In the east of the northern region of America, man first began to tame the vegetation. It was the first step towards abandoning a nomadic lifestyle based on hunting and gathering in order to finally settle on the land. According to a study by the University of Utah, this movement was the result of a population explosion and food shortages, which forced the natives to seek a new form of subsistence.

“Domesticated plants and animals are part of our daily lives, so much so that we take it as something normal. But it represents something very unique in human history. It has allowed more people to live in the same place. In the end, it paved the way for the emergence of civilization,” says anthropologist Brian Codding, who led the study, published in the specialized journal Royal Society Open Science.

“For most of man’s history, people have lived on wild foods – anything they could hunt or collect. It was only in a relatively recent time that they made this shift to a very different method of acquiring food. It’s important to understand why this transition occurred,” adds undergraduate student.

The work focused not on the institution of the agricultural economy, but on the initial step of domestication, when the first people in eastern North America began to plant species they collected from the wild, such as sunflower, pumpkin, elderberry and Chenopodium berlandier, popularly known as goose-foot seed, a pseudo-cereal very close to quinoa. Codding, assistant professor of anthropology at the University of Utah, says that at least 11 plant domestication events were identified in world history, starting with wheat, 11,500 years ago in the Middle East. The one in eastern North America, which began 5,000 years ago, was the ninth and occurred after a population explosion between 6,900 and 5,200 years ago.


For many years, two theories have been competing to explain the cause of domestication on the American continent. The first claims that population growth and consequent food scarcity have encouraged the planting of species that were already collected. The other theory, called “niche building” or “ecosystem engineering,” basically says that intentional experimentation during times of abundance led people to manipulate wild plants and increase food stocks.

“We argue that human populations increased significantly before the domestication of plants in eastern North America, suggesting that people are domesticated when the population is greater than the natural food supply,” says Weitzel.

According to him, the transition to domestication has allowed human populations to increase dramatically around the world, making the modern lifestyle possible. “People have begun to live near the countryside. When you have sedentary communities, they begin to expand. Villages grow into cities. Once you have this, you have all kinds of social changes. We don’t see societies divided into levels until domestication occurs,” he explains.

The region of North America covered by the study includes the states of Missouri, Illinos, Indiana, Ohio, West Virginia, Kentucky, Tennessee, and Arkansas, as well as portions of Oklahoma, Kansas, Iowa, Virginia, North Carolina, Carolina, Georgia, Mississippi, and Louisiana, all in the United States. “This is the region where edible plants have begun to be domesticated of their wild variants. Everywhere else in North America, grains were imported from many parts of the continent, particularly Mexico and Central America,” Weitzel says.

Genetic analyses have already indicated that the region played a key role in the domestication of plants in the Americas, dating for example that cassava would have been domesticated there between 8,000 and 10,000 years ago.

“But until now we had no archaeological evidence of this,” argues Jennifer Watling, an archaeologist at the University of São Paulo’s Museum of Archaeology and Ethnology.

The evidence includes phytolites, small pieces of petrified plants found in the middle of the clay. They measure about 20 microns, or 0.02 millimeters. To compare, next to a grain of fine sand, proportionally a tennis ball next to a football field.

Watling and his colleagues analyzed the remaining seeds and other remains of older plants found at the archaeological site, as well as the artifacts used in the feeding process.

“In this study we were able to find microbotanical remains associated with anthropogenic settlements dating from 5 to 6 thousand years ago. We are associating a type of site in the region with the domestication of cassava,” explains the researcher.