May 2016 Features

In Our Backyard

Faculty_BarrierWhen the Alumnae Bulletin heard that the National Geographic Society is funding Assistant Professor of Anthropology Casey Barrier’s fieldwork at America’s first city, we were curious to learn more. In the following conversation, he spoke about anthropological archaeology, how he came to the field, and his current work at the pre-Columbian city of Cahokia.


Alumnae Bulletin: What exactly is anthropological archaeology?

Casey Barrier: Simply put, anthropological archaeologists apply archaeological methods to ask anthropological questions about the past. Let me start with some general definitions. Like many of the disciplines in the social sciences and humanities, anthropology studies human societies and cultures and cultural and social change. But what distinguishes anthropology is its holistic focus, which includes humans in all areas of the world and in all time periods and even our closest nonhuman primate relatives.

Archaeology is a set of methods to study humans in the past by recovering and analyzing the artifacts—the tools, pieces of art, buildings, even altered landscapes.

Bulletin: How did you come to the field?

Barrier: In my first few semesters of college, I took a set of courses that would naturally lead down career paths that didn’t interest me. But I had taken a few anthropology courses, and what I was reading about and thinking about for those courses was what I was interested in. How was my own society organized economically, politically, socially? Why? Why are there haves and have-nots?

And I was intrigued by anthropological archaeology, which looked through the perspective of both the present and the long term to understand how societies have dealt with these big perennial questions.

Bulletin: How does that manifest in your research?

Barrier: Scholars tell us that the two major transitions in world history have been the origins of agriculture and of urbanism. And they both happened in our own backyard, here in eastern North America, and that’s what I study.

The adoption of the farming lifestyle happened independently in only eight to 10 places around the globe, and there are only a few places where humans, without being spurred by other cultures and societies, adopted urban lifestyles. And eastern North America was one of them, and most people aren’t aware of that.

When I meet people at parties and they find out that I’m an anthropological archaeologist, they immediately ask me about Egypt and the pyramids. When I tell them I work in eastern North America, they say, “Oh, is there anything interesting to find here in the United States?”

Bulletin: So is there?

Barrier: About 3,000 to 4,000 years ago in the mid-South region and eastern North America, Native Americans domesticated a relative of quinoa called Chenopodium and began farming. Then about 1,000 years ago, the process of incipient urbanism occurred at a site called Cahokia, just across the river from St. Louis, Missouri.

The largest pre-Columbian, pre-European-contact archaeological site north of Central Mexico, Cahokia had an estimated 10,000 people settled in an area of 15 to 20 kilometers. And they built mound monuments that were made of basket loads of earth transported by people and engineered to more than 100 feet tall. The largest is called Monks Mound, and its base is larger in area than the Great Pyramid of Giza’s.

This is the time period, with the start of Cahokia around 1000 AD, that I work on. This marks a new way of cultural life that archaeologists call the Mississippian, which spread throughout much of eastern North America over the next 500 years until the Spanish came in the 1500s.

It was also at this time that a handful of domesticated crops, originally domesticated in Mexico—maize, squash, beans—made their way into Cahokia and Eastern North America. So this process of moving together, being able to support large populations, and building a city was happening alongside the adoption of corn agriculture.

Bulletin: What is the nature of your research there?

Barrier: A host of scholars have been working at Cahokia for decades, but there is a major missing piece: the start of the urbanization process. Once it became a major center of population, Cahokia was occupied for 300 years, more or less. So now we see its final form—300 years of urban movements, of reorganization, of digging up and building houses, neighborhoods, plazas, mounds—but it’s hard to identify the instance when this process started.

My next project aims to get a glimpse of these first few decades of population aggregation, urban and institutional changes, and transformations to the landscape. The National Geographic Society has awarded me a research grant to conduct a geophysical survey of large swaths of the landscape, to take more or less an X-ray of what’s under the ground.

In the past, we would have to spend our effort on opening up this large area and excavate, just to see small segments of the archaeological remains left behind. Now, with geophysics, we can survey large areas in short amounts of time and produce what are basically X-rays of the foundations of buildings, of houses, of cooking pits, of trash pits, of earthen mounds that have since been plowed down.

I will be working with colleagues—including Bryn Mawr students—on those areas where we think initial populations were aggregating at Cahokia. We will be conducting the geophysical survey and then test excavations to do what we call ground-truthing to determine whether what we’re looking at is actually what we think it is. And from the materials we recover from those excavations, we can do radiocarbon dating to date the time period.

From there, we can apply for further research grants to conduct longer-term studies into this process of transitioning to an urban lifestyle and shifting into corn-based agriculture to support larger sedentary populations.