Rise of Civilization in Peru—Maize (Corn)

Corn, or maize, is native to the Americas. When the Spanish arrived and saw the plant, they called it “corn,” which was the original English term for any cereal crop. In North America, its meaning has been restricted since the 1800s to maize, as it was shortened from “Indian corn.” The term Indian corn now refers specifically to multi-colored "field corn" (flint corn) cultivars (meaning selected and cultivated by humans). 
    Radiocarbon dating of maize (corn) in the Americas has always centered on Mexico. In fact, “the earliest physical evidence for domesticated maize, what some cultures call corn, dates to 8,700 years ago” (6,700 B.C.), according to a 2009 news release from the National Science Foundation.

According to Dolorest Piperno (left) archaeologist and staff scientist of the Smithsonian, "We found the remains of maize and squash in many contexts from the earliest occupation levels," said the senior scientist and curator of archaeobotany for the Smithsonian's Museum of Natural History in Washington, D.C. This report places maize domestication in Mexico about 1,500 years earlier than previously documented there, which is 1,200 years earlier than the next earliest dated evidence for maize in Panama, according to Anthony Ranere, Department of Anthropology at Temple University in Philadelphia.
    "This indicates these two crops were being routinely consumed nearly 9,000 years ago," Piperno added. She also said that phytolith and starch grain evidence allowed researchers to trace the dispersal of maize as a domesticated crop from its origin in or around the Xihuatoxtla Shelter, located in the Rio Balsas valley in the state of Guerrero, Mexico.

From there, according to the Smithsonian team, it reached Panama by 7,600 years ago (5600 B.C.) and shortly thereafter to Colombia and Ecuador, and to Uruguay by 4,600 years ago (2600 B.C) On the other hand, and evidently unknown to the Smithsonian, researchers in South America have found evidence of maize along the north coast of Peru dating to a much earlier date than 4,600 years ago—to a radiocarbon date of 7000 years ago, or 5000 B.C., while Piperno’s dates are dated through “cal BP,” meaning calibrated years before the present, which sounds official, but is based on dendrochronology (tree ring dates), since radiocarbon dating has been found to have “wiggles” in it (that is, scientists are finally acknowledging that the amount of carbon in the atmosphere, which is used to create radiocarbon dates, has not been consistent over time).

By way of further explanation, Before Present (BP) years is a time scale used mainly in geology and other scientific disciplines to specify when events in the past occurred (above). Because the "present" time changes, standard practice is to use 1 January 1950 as commencement date of the age scale, reflecting the fact that radiocarbon dating became practicable in the 1950s. The abbreviation "BP", with the same meaning, has also been interpreted as "Before Physics"; that is, before nuclear weapons testing artificially altered the proportion of the carbon isotopes in the atmosphere, making dating after that time likely to be unreliable (it is interesting that science, while recognizing that nuclear testing has effected the amount of carbon in the atmosphere, that the Creation, Flood and crucifixion events are ignored, each of which would have altered the amount of carbon-12 to carbon-14 in the atmosphere and skewed testing results).
    To compensate for actual calendar dates, like those figured in the Norte Chico dating, the “cal BP” is based on an even more questionable tree ring dating system that is fraught with problems of its own—one of which is that it has been found that a tree can have up to five separate rings per year, and that these extra rings are often indistinguishable, even under the microscope, from annual rings.
    Another problem with the Mexico Xihuatoxtla Shelter discovery is that the researchers found that the maize they discovered had already been domesticated—that is, these samples would not be the earliest existence of domesticated corn. "We did not find evidence for the earliest stages in the domestication process," said Ranere. "We need to find more ancient deposits in order to document the beginning of the process."
    So where were these “earliest” domestication processes achieved? In Mexico, Mesoamerica, or in Andean South America?

Workers, under the direction of Field Museum curator Archaeologist Jonathan Haas, search for corn residue in Caral-Supe and Norte Chico. The work was long and laborious, but the results were outstanding;
Left: Dr. Haas digging in a trash midden at Caballete in Norte Chico; Right: Map showing Norte Chico in relation to Lima, Peru and the northwest of South America
    Since the early 21st century, the area of Norte Chico along the northern west coast of Peru has been established as the oldest known civilization in the Americas and one of the six sites where civilization originated independently in the ancient world (see the earlier post, “The Earliest Americans—Norte Chico,” Thursday, March 5, 2015).
    The question facing Haas and his team was whether or not maize (corn) was the key to the rise of early civilization in Peru? For years, archaeologists have debated the economic basis for the rise of civilization in the Andean region of Peru. The prevailing theory advanced the notion that the development and consumption of marine resources was the primary mover. Now, however, a team of research scientists have found evidence to dispel that theory.

A 5000-year-old corncob found at a pyramid at the ancient Peruvian site of Caral-Supe, which appeared in the Proceedings of the National Academy of Sciences, Haas’ team of researchers examined and evaluated ancient microscopic residues of maize in the form of pollen, starch grains and phytoliths (plant silica bodies) found in soil, on stone tools, and in coprolites from ancient sites, using 212 instances where Carbon-14 dates were obtained. They focused on 13 desert valley sites of Pativilca and Fortaleza, north of Lima (see map), where they found broad botanical evidence that indicated extensive production, processing and consumption of maize between 3000 and 1800 B.C. The two most extensively studied sites were Caballete, about six miles inland from the Pacific Ocean and consisting of six large platform mounds arranged in a “U” shape, and the site of Huaricanga, about 14 miles inland, featuring one large mound and several smaller mounds. They targeted residences, trash pits, ceremonial rooms, and campsites, but most of the samples were taken from trash pits of residences.
    Though very little evidence of corn consumption had been found in Peru dating back to the time of Norte Chico, Haas and his colleagues figured these people just had to be eating corn. So they decided to look harder. First, they searched archaeological sites north of Lima for proof that the ancient Peruvians had been growing corn. They found lots of old maize pollen. Then, they went looking for pollen on the stone tools the residents of Norte Chico used to cook. They looked under the microscope, and "lo and behold, the large majority of the tools are being used to process maize," Haas remarked.
    Finally, they looked in the fossilized human midden and found anchovy bones—and lots of corn starch. Of 126 soil samples analyzed, 61 contained Z. mays pollen, consistent with the percentage of maize pollen found in pollen analyses from sites in other parts of the world where maize is a major crop and constitutes the primary source of calories in the diet.
    Nor is that all—it turns out that sweet potatoes were the second most popular carbohydrate, and guava the most popular source of sugar. Haas’ report shows that "Rather than being a maritime-based society, Chico Norte was an agriculturally based society.” This means that  South America falls in line with the rest of the civilizations of the world.
    Prior to this latest discovery about corn, it was generally accepted by historians that maize was domesticated in the Tehuacan Valley of Mexico. The Olmecs and Mayans cultivated it in numerous varieties throughout Mesoamerica, cooked, ground or processed through nixtamalization. Beginning about 2500 BC, the crop spread through much of the Americas. The region developed a trade network based on surplus and varieties of maize crops. However, as can now be seen, corn was being grown in the coastal region of Chico Norte in South America as early as 5000 B.C. (See the earlier post, “The Earliest Americans—Caballete,” Friday, March 6, 2015 for some of the details of this find).

Top: Morado (cantena) Purple Maize, grows in both coastal and highland areas, and has recently been found to have unusually high levels of antioxidants and anti-inflammatory properties. It is also made into Peru’s famous purple corn drink Chica Morada, which is a “powerhouse of nutrition”; Bottom: Peru grows Andean cobs with especially large kernels
    While it might be debated further, it would appear from unadjusted radiocarbon dates that maize or corn originated in Mexico; however, the question arises that since there were no development sites before the Olmec (1500 B.C.) how did that occur? According to Olmec histories, “Somewhere around 1000 BC, the first of Mexico's ancient civilizations, the Olmecs (or XI, called the “Mother Civilization of the Americas”), though they were not on the scene until at the earliest 1500 B.C. or the latest 1000 B.C., either date is long after those radiocarbon dates of Andean South America. The Olmec established themselves in what are now the states of Veracruz and Tabasco. In their wake came the Xicalancas, Teotihuacan, the Zapotecs and Mixtecs of Monte Alban, the Otomies, Tepanecs, Maya of Yucatan, the Toltecs, Aztecs, and dozens of smaller, citied groups."