Pounding SignaturesGAMBIER, Ohio (July 23, 2009) Rebecca Warren '09 spent part of her Kenyon career pounding onion-like bulbs with stone, just like a Neanderthal doing some paleolithic kitchen prep. Or, for that matter, like a chimp breaking open nuts.
That work-along with painstaking hours at the microscope-has put Warren in some rare scientific company. She and her faculty mentor, Associate Professor of Anthropology Bruce Hardy, are coauthors of a recent article in the prominent journal Nature. Together with some of the world's leading primate experts and paleoanthropologists, they are helping to launch a new field: primate archaeology.
The field is rooted in the fact some of our primate cousins, like chimps, use stone tools in much the same way as early humans. Primatologists, however, have traditionally studied the behavior of living animals, not the artifacts their forebears left behind. By contrast, archaeologists have had to theorize about prehistoric human behavior based on their reading of artifacts.
Primate archaeology brings the two disciplines together, with the goal of learning more about the origins of tool use and human evolution generally. The Nature article, promoting this collaboration for the first time to the wider scientific community, grew out of an October 2008 symposium at the University of Cambridge, in England, where Hardy presented research that he and Warren had conducted at Kenyon.
Their contribution involves residue analysis-using a camera-outfitted microscope to examine stone tools (both actual prehistoric artifacts and modern-day simulations), scrutinizing at the cellular level the bits of starch or hide, say, that have remained, as well as the patterns of polishes and striations on the stone's surface. "Pounding signatures" can yield information on how a tool was used.
"My interest is in the potential to push the archaeological record back farther than ever before," said Hardy. "The earliest tools we can recognize are flaked stone about 2.5 million years old. There's got to be something before that. But how do you recognize it?" Residue analysis, combined with comparisons to the tools of modern primates, might provide useful leads.
Hardy and Warren's work may also help answer a basic evolutionary question: why would our ancestors have pounded their food in the first place? The two found that the pounding process can eliminate toxins, such as cyanide, in some plants, while also producing glucose, sweetening the taste.
"It's because there are no definitive answers in archaeology-that's what really drew me to it," said Warren, who spent two summers at the Koobi Fora Field School in Kenya, one of the world's premier locations for excavating hominin artifacts. Warren, who graduated this spring with highest honors in anthropology, is working at Hohle Fels, a paleolithic cave site in Germany, this summer, and will begin a doctoral program this fall at the University of Connecticut.
"I like to think of archaeology as a sort of puzzle where some of the pieces are missing or broken and, despite this, your goal is to try to figure out and recreate what the picture was. Your best tools are how observant you are and how much data you can collect."