Religious ritual evolved with society in Mexico

ANN ARBOR—University of Michigan archaeologists have demonstrated that religious ritual and social organization evolved together among Mexico’s prehistoric Zapotec Indians.

Their study, published in the current issue of the Proceedings of the National Academy of Sciences, provides some of the first physical evidence supporting the assumption that religious ritual co-evolved with social complexity.

Their findings suggest that rituals evolved along with changes in social organization from nomadic hunter-gatherers to permanent village dwellers and eventually stratified societies.

To chart the evolution of ancient religious practices, U-M anthropologists Joyce Marcus and Kent Flannery used radiocarbon dating to date ritual buildings and features found in the Oaxaca region. They found that the earliest ritual feature, a cleared area resembling a Native American dance ground, dated to about 8,600 years ago.

At this time, the population was nomadic, and most rituals were performed when the maximum number of families came together to participate. With the advent of an agriculture-based society centered in permanent villages, the researchers found that rituals and temples became less accessible to all, echoing the increase in social inequality. In addition, some rituals began to be performed at specific times each year.

"In the days when people lived by hunting wild animals and collecting wild plants, major rituals were held during those times when the largest number of people lived together, usually the season of abundance," said Marcus, professor of anthropology and curator of Latin American Archeology at the U-M Archaeology Museum.

"The rest of the year, people were so nomadic that they didn’t have a quorum. It looks as if these ad hoc rituals were open to everyone."

After people began practicing agriculture and they settled down in permanent villages, some rituals could be scheduled to coincide with solar or astral events, like the equinox. And some rituals were held in buildings so small that it’s clear many people were excluded from participation, she said.

"When complex societies with social stratification arose, some rituals were conducted by full-time priests, excluding even more people from major participation," she said. "These societies had formal temples which, in the case of the Zapotec, seem to have been torn down and renovated about every 52 years, in accordance with their religious calendar."

This model for the evolution of ritual needs to be tested against data from other areas of the world, Marcus said.

"But the findings show that in the Oaxaca region, each time society took another step toward increasing complexity, ritual became more elaborate and formal, and was performed by a smaller and smaller percentage of society," she said. "The result was a widening gap between trained religious specialists and lay people. By contrast, in earlier times, everyone seems to have been involved and the venues where ritual was conducted were less elaborate."