An interpretation of new data suggests that ritual activity took place in southern Mexico more than 9,000 years ago. But the interpretation has sparked a debate among Mesoamerican scholars

On a balmy summer evening more than 9,000 years ago, a couple of dozen people gathered outside their oval huts on a small plaza demarcated by two rows of boulders. There was quiet anticipation in the soft air of ancient Mexico. The modest plaza, a rectangular area 60 feet long and 21 feet wide, had been carefully swept clean during the day in preparation. After a meal of squash and beans, cooked nearby over gathered twigs, the inhabitants began to play music and dance in a ritual that echoes down thousands of years of human habitation in the Oaxaca Valley in Mexico.

That compelling picture of what may be the oldest known ritual space in the region comes from new data recently gleaned from a 40-year-old excavation. The husband-wife team of Kent Flannery and Joyce Marcus of the University of Michigan in Ann Arbor see in that data an early link in the chain of societal development that led to the Zapotec culture that even today dominates the valley. But a host of other archaeologists aren’t convinced that the data supports their vision. They say that the results published in December in the Proceedings of the National Academy of Sciences are an example of using data to fit a preconceived theory.

The debate centers on a nondescript agave field just off the highway that runs from Oaxaca City to the town of Mitla. During the mid-1960s, Flannery conducted a survey of the region, and noted a scattering of flint tools at the site, called Gheo-Shih by the locals. (The name, in the Zapotec language, means “River of the Gourd Trees.”) Flannery asked Yale University’s Frank Hole if he would oversee an excavation there given his expertise in stone tools. Hole, a lanky and quiet man, agreed, using his vacation time to do the work.

After digging several test pits, Hole found a few big stones. “I followed the line of rocks, and the line got longer and longer—and then I found a parallel line of rocks.” On one side, he noted remains of oval-shaped huts, seemingly similar to those used for millennia in the area. On the other side was scattered debris. But the area in between lacked debris or archaeological features; it was as if it had been swept clean. Hole, who has followed modern- day Iranian herders on their migrations in an attempt to understand the movements of nomadic peoples in the past, thought the clean area was a lane between houses or an open plaza that was separate from domestic activities. As to age, he wasn’t sure, given that the area had been plowed over the years and therefore the stones might have been disturbed. “And much of the site was eroded.” But he adds that his “mental image” at the time was of a place in front of houses that had been swept clean.

Hole found bits of charcoal on the site, but they were too small to date back in 1967. But with the advent of Accelerator Mass Spectrometer dating in recent years, researchers can glean data from samples as small as a milligram and as old as 100,000 years. So Marcus and Flannery obtained a grant from the Foundation for the Advancement of Mesoamerican Studies to do the dating.

The results, laid out in the December paper, were that the swept space dates to approximately 7600 B.C., some three millennia before the first substantial villages were established in the region. The era was also a period when Mesoamerican agriculture was first practiced in the form of beans and squash cultivation.

The results pleased Marcus. She switched from majoring in English to anthropology when a college professor— the renowned archaeologist J. Desmond Clark—asked her if she wanted to write the one-millionth analysis of Shakespeare, or be the first to dig a site in Africa. She later married Flannery, an archaeologist who has focused on the agricultural development of Mesoamerica.

The Gheo-Shih site lies approximately 5,500 feet above sea level on the floor of the temperate Oaxaca Valley, a Y-shaped cleft nearly 60 miles long and 15 miles wide between central Mexico and the Yucatan. To the north rise the majestic Sierra Madre Oriental, to the south are the peaks of the Tlacolula. Large animals thrived in the colder and wetter climate during the last ice age, but around 8000 B.C. the weather grew warmer and drier, and hunter-gatherers turned to smaller game and fish. It was a bountiful environment. White-tailed deer and the collared peccary roamed the highlands among oaks and pines, while the tapir, the jaguar, and the howler and spider monkeys thrived in the lower altitudes. Ducks and wild turkey abounded, as do birds such as the quetzal, which provided feathers for elaborate costumes down the ages.

By 7000 B.C., small bands of hunters and gatherers roamed the Oaxaca Valley, dispersing during lean seasons to gather food, and coming together into larger camps during times of abundance. Gheo-Shih appears to be a summer encampment where two dozen or more people assembled during the rainy season to gather mesquite pods, hackberries, and plant squash and gourds. Just 1.5 miles to the north, the Michigan archaeologists found a cave called Guila Naquitz. Located nearly 1,000 feet higher than Gheo- Shih, the cave appears to have been occupied about the same era as Gheo-Shih by a family of four to six people during the dry season between October and December—a time when acorns and pinon nuts are ready to harvest.

The two sites, say Marcus and Flannery, provide an unprecedented view into the lives of early Archaic peoples in the New World, and in an area that became a nexus of early Mesoamerican states. “Both sites might have been used by the same group during different seasons,” say the authors. But the uses were quite different. While the family focused on gathering food during the fall, the larger group at Gheo- Shih found time to make holes in flat circular stream pebbles and hang them as ornaments. “They also created the earliest dated ritual feature from ancient Mexico,” say the two archaeologists, referring to the cleared space.

The apparent fact that this space was swept clean, was clearly marked by parallel lines of rock, and was bounded by abundant artifacts on both sides—including remains of shelters—provides compelling evidence of ritual, according to the paper. “The implication is that certain rituals, for which part of the camp was formally set aside, were held during times when the maximum number of families could participate,” they write.

To bolster their argument, Marcus and Flannery cite evidence for other rituals during the Archaic period. At Coxcatlan Cave (5000 B.C.) in the Tehuacan Valley 96 miles to the northwest, excavators in the 1970s found evidence of baskets of harvested wild plants, along with the grisly remains of individuals who appear to have been beheaded, cooked, and eaten. That important find, they note, showed that the human sacrifice which was so common in later Mesoamerica began long before the formation of large states, and that such sacrifices might be tied to harvest rituals.

A Debatable Interpretation

But some scholars take issue with the assertion that the space at Gheo-Shih was used for rituals. “There is controversy over the dating of these parallel lines of rocks,” says Stephen Houston, an archaeologist at Brown University in Providence, Rhode Island. Much of the archaeological material is 12 to 20 inches below the surface, explains Marcus Winter, an archaeologist with the Mexican National Institute of Anthropology and History in Oaxaca who is familiar with the site. “All those years are compressed into that thin space,” he adds. Such compression can make it difficult to distinguish among artifacts of different eras. “How do they know the rocks weren’t moved?” he asks. Winter notes that the area was settled in the late Post Classic period, and he suggests that what appears to be an Archaic ritual space might be a road built in Spanish colonial times.

But Joyce Marcus dismisses such concerns as groundless. “We do have a stratigraphy at Gheo-Shih,” she says. Two layers contain solely Archaic artifacts, Marcus says. The upper level dates to circa 5000 B.C. The lower area included burnt twigs dated to roughly 7600 B.C. “No colonial roads were found, nor were any colonial artifacts,” she adds.

The second objection to the thesis put forward by Marcus and Flannery is the function of the swept area. The couple proposed long ago, before the dating results were in, that the space was likely used for dance; in their National Academy of Sciences paper they note that initiations or athletic contests might be other viable explanations.

But archaeologists have excavated very few Archaic sites in the region, so drawing conclusions about the use of space is treacherous business, says Arthur Joyce, an archaeologist at the University of Colorado at Boulder. “We don’t really understand the Archaic, since the number of sites excavated is pretty limited.” Adds Winter: “Seeing a ritual space based on two lines of rocks is questionable.”

Marcus insists that she and Flannery have always been “open-minded” on what sort of ritual took place. “Who knows?” she says. “The point is that it was swept clean of artifacts while there were lots of artifacts all around that cleared space.” She adds that she wants “many more wellexcavated Archaic sites” in order to have a better picture of life in that period. Arthur Joyce, however, says that dance, athletics, and initiation rites are all plausible explanations, but that it is just as plausible to see a road or passage. Hole agrees that “we don’t have tangible evidence of what they were doing.” And he adds that Flannery has “a good imagination” and likes to see things “in a sequence,” that is, connected to later developments in the area. Nevertheless,

Hole says “the idea of people dancing in this street strikes me as plausible” given that dancing probably dates back to Paleolithic times. Charles Spencer, the curator of Mexican and Central American archaeology at the American Museum of Natural History in New York, concurs that Flannery and Marcus’s theory is “plausible.” Some archaeologists may agree with some points and disagree with others, he notes, “but overall their work is sound.”

Connecting Dots

In addition to the debate over dates and function, another point of contention is the deeper philosophical dispute that is as pronounced as the line between the Gheo-Shih swept space and the artifact-strewn area. While Marcus and Flannery adhere to a model of cultural evolution, articulated by their late colleague at Michigan, the esteemed anthropologist Roy Rappaport, Winter and Joyce are drawn to a more variable view of how humans organized themselves, a view gaining favor, they say, over the more traditionalist view of cultural evolution.

That difference plays out in how Marcus and Flannery relate the finds at Gheo-Shih and Guila Naquitz to the much later sedentary life found in Oaxaca after the Archaic period ends about 2000 B.C. Around that time, maize cultivation allowed people to become more settled. By 1450 B.C., a large village had emerged at San José Mogote less than 60 miles from Gheo-Shih. About five to 10 times the size of an Archaic camp, the village was made up of nuclear families as well as a larger social unit that used a ritual building by about 1350 B.C. “The best ethnographic analog for this building seems to be what scholars call a ‘men’s house,’” according to the Michigan archaeologists. Such houses are the centers of a group descended from a real or mythic ancestor, and typically are accessible only by a small group of men who have been initiated into secret rituals.

San José Mogote had a number of so-called “men’s houses,” each with one 12-foot-by-18-foot room, plastered with lime, and set on a platform facing just slightly north of east “which hints that they were aligned with the sun’s path at the equinox,” the authors say. This indicates “that ad hoc ritual had been joined by calendric ritual.” Living in one place year-round would allow solar or astral events to be used in architecture. A pit in the center of the room, filled with lime, may have been used for taking a ritual plant such as tobacco, jimson weed, or morning glory. Later Zapotec are known to have chewed tobacco and lime before a raid or to ward off illness.

By 1100 B.C., the village grew into a settlement of 1,000 people, and differences in rank began to appear. The elite lived in multistructure residences, adorned themselves with jade and mother-of-pearl, and deformed their skulls as a sign of nobility. Soon, men’s houses were replaced with temples on pyramidal platforms that may have served an entire region, not just one part of a village. One temple constructed during the 7th century B.C. measured more than 42 feet by 39 feet, and was again oriented slightly to the north of east. An early monument shows rivals with their hearts torn out. Charcoal from one roasting pit dates to 690 B.C. Obsidian stilettos, shaped to resemble stingray spines, were the means for ritual bloodletting, Marcus and Flannery say. The temple was burned sometime around 700 B.C., presumably by a rival group.

For Marcus and Flannery, the Archaic sites provide exciting evidence of the early evolution of what eventually became the Zapotec culture. The new dates “provide chronology for a model of the coevolution of ritual and society,” the authors write. Charles Stanish, an archaeologist at the University of California in Los Angeles who studies ancient Peru, finds this evidence compelling. He notes that there are Archaic sites dating to 3000 B.C. in Peru with public spaces in the form of modest ballcourts and pyramids, which eventually evolve into the more complex structures of the first millennium A.D. “You can make a pretty good case [in Peru] for continuity” over that lengthy period. Though beliefs likely change radically over millennia, ritual behavior often does not, he says. “A person in 8th century Homeric Greece transported to 13thcentury England would have a sense of the ritual—they would get the point” though they would not understand the detailed belief system.

But other scholars say that connecting these archaeological dots does not provide a clear view of cultural evolution in the region. “There’s a good deal here that is fairly speculative,” says Houston. He believes that the Marcus and Flannery paper “constantly blurs the line between speculative or analogical claims and decisive evidence.” For example, identifying the structures as “men’s houses” is tricky, given that they are “difficult to discern even in far better understood settings.” The orientation of buildings may relate to the rising sun, but nothing more. He is also suspect of using ethnographic analogies over such vast periods of time. Joyce adds that many archaeologists today reject the idea of a universal series of progressions in culture— from band to tribe to state to empire. “I’d say history is more contingent and variable,” he adds. Winter agrees that Marcus and Flannery take ethnographic assumptions too far.

Though interpretations of the evidence vary, everyone agrees that the new dates provide insight into the little-understood Archaic period, and that they back up the widely held view that hunter-gatherers in the region began to settle and practice agriculture sometime around 7000 B.C. “We need long dated sequences for other valleys, so we can compare the developmental history in Oaxaca with sequences in other valleys,” Marcus says. “The future is exciting.” And it’s sure to be controversial.