Digging up answers

Digging up answers

September 1, 2002

Andrew Nelson's special gift is the ability to reach across time to learn from the past.

No, the University of Western Ontario professor is not a television psychic. He's an archaeologist and physical anthropologist-and his research involves studying ancient skeletal and mummified human remains. Along with his colleagues, Mike Spence, Chris Ellis, Christine White and Robert Hegele at The University of Western Ontario's new Bioarcheology Research Facility, Nelson is literally digging up answers and applying cutting-edge tools and technology to better understand the mysteries of ancient civilizations.

"The idea is to understand peoples of the past by studying them from their actual bones," says Nelson. "You can study written documents, buildings, and pottery-you can study all sorts of other things. But if you study the actual people of the past, it's a very immediate, very empathic way of reaching across time to other people and other cultures."

Nelson works primarily on remains discovered near the town of San Jose de Moro, in northern Peru's Jequetepeque Valley (pronounced HE-ke-te-pe-kay). By examining skeletons from a sequence of cultures covering 600 years in the same location, Nelson is learning how cultures change and evolve. He's also drawing conclusions about the ancient peoples' daily lives and values. A prime example? The lives of the area's Lambayeque and Moche peoples are literally written on their skeletal remains, dating from 450 to 1500 AD.

Though the skeletons stay in their native Peru, Nelson brings home small samples of tissue and bone to analyze in his lab at London's University of Western Ontario. The new research facility provides the researchers with the analytical equipment and tools they previously lacked. In the past, archeologists had to send material to labs in other parts of Canada or to the United States to be analyzed. The new center will allow the team to test materials in-house, and to build up a cadre of expertise unparalleled anywhere in the country.

Just a decade ago, archeologists would not have been able to uncover the secrets that skeletons and mummies now reveal. The use of DNA analysis and isotopes to study bone chemistry has opened up a new field of information about the peoples of the past. DNA results can now reveal familial relationships and ancestry, helping archeologists and anthropologists understand how cultures evolved over time. For example, genetic sequencing can bring hereditary diseases to light. And isotopic analysis can reveal detailed data about what people ate and drank, the ecological resources available to them, and their patterns of movement.

Nelson and his team, are trying to understand ancient cultures by creating osteobiographies of individuals. An osteobiography is a personal reconstruction of the life of someone who lived a long time ago-a technique used to "put the flesh back on the bones." His colleagues, physical anthropologist Christine White, and geochemist Fred Longstaffe perform isotopic or biochemical analyses of skeletons based on a simple theory: you are what you eat. From bone and teeth, she can reconstruct long-term dietary patterns. From other tissue, like hair, she can reconstruct seasonal changes in diet and determine what kind of foods an individual was consuming at the time they died.

Nelson and White were able to create this type of osteobiography for a skeleton excavated from the San Jose de Moro site in 1997. What did they discover after they "put the flesh back on the bones"? They were able to determine that the skeleton they had found belonged to a woman in her 40s. She once survived a violent and painful blow to the centre of her rib cage, and also suffered from arthritis and a bad back. Although young by today's standards, the woman was considered quite elderly for the Precolumbian population of that time. Artifacts buried with her suggest that she was of high status and spent much of her life spinning cotton or wool.

Benefits

Traditionally, archeologists assess cultural change by examining the artifacts buried with skeletal remains. Each new style of ceramics, carefully excavated from the earth, was assumed to correspond to a new group of people who had replaced the previous culture in a given area.

Today, archeologists using the modern tools of DNA sampling, isotope analysis, and radiography (X-rays) at the University of Western Ontario's new Bioarcheology facility can determine much more about ancient peoples and their cultures than ever before. Now, when they examine skeletons and artifacts, those preserved pieces of history tell a different story. They tell the tale of the same people adapting and evolving over time, adopting new tools and new styles. "When we look at the DNA of the people themselves, it looks like it is the same group of people changing the way they do things," says archeologist Andrew Nelson, principal investigator at the UWO's new centre. "Which is a very different model of cultural change."

Understanding human cultures from the past is critical if we are to understand human cultural diversity in the present, says Nelson. The bones, tissue, and artifacts uncovered in countries far from Canada-such as Peru, Guatemala, and Mexico-have knowledge to offer our own cultures and societies, particularly about the ways in which diverse peoples related to each other and interacted.

"The relations between cultural groups now are the product of histories that go back thousands and thousands of years," says Nelson. "So archeological work gives us the temporal context to understand what's going on in the world today. It gives us a better appreciation of the world in which we live."

Partners

The University of Western Ontario's new Bioarcheology Research Facility is being financed in part by the Canada Foundation for Innovation (CFI), and in part by the Ontario Innovation Trust. The Trust, established by the Ontario government in 1999, funds the capital cost of research needs at Ontario universities, hospitals, colleges, and other research institutions. The university's Alumni Association is also raising matching funds for the facility.

Both the CFI and the Trust's investments are designed to help institutions retain and attract accomplished, visionary researchers. The goal of the Bioarcheology facility is to foster a synergy among researchers that will make the facility a world leader in archeology and anthropology.

"The Ontario Innovation Trust's board of directors is pleased to support the type of unique and innovative research undertaken at UWO's Bioarcheology Research Facility," says Ken Knox, president of the Trust. The board is particularly interested in what the archeologists' research about past cultures can tell us about our health in the future. "The combination of state-of-the-art infrastructure, the international expertise of the team, led by Dr. Nelson, and other resources available at UWO provides researchers with better insight into the interactions of the environment and diet on our health," says Knox.