After more than two decades in the field, the issues and questions surrounding human nutrition and evolution are even more compelling to Sobolik than when she started her research.
As an undergraduate biology student at the University of Iowa, she went on a summerlong archaeological excavation for extra credit. She fell in love with the work and, ultimately, ended up shaping the field of archaeological biology, of which paleonutrition is a part. She went on to earn her master’s and Ph.D. at Texas A&M, whose Anthropology Department is known for interdisciplinary study.
At UMaine, Sobolik joined the anthropology faculty and UMaine’s interdisciplinary team of climate change scientists who bring diverse perspectives from many academic backgrounds.
Paleonutrition is a small but significant component of climate change research, says Sobolik, who recently co-authored the most comprehensive book on paleonutrition since 1979 with Mark Sutton, professor emeritus of anthropology at California State University – Bakersfield, and Jill Gardner, principal investigator for ASM Affiliates.
“The development of agriculture was one of the biggest decisions we have made in changing how we interact with the planet,” she says. “Then there was the industrial revolution, and now we have the industrial revolution to the extreme.”
Today, technological advances in paleonutrition have given researchers better tools to relate the past to the present. For instance, the ability to analyze DNA in paleofeces provides a comprehensive look at everything humans ate — plants, animals, bacteria and viruses. It also allows researchers to be certain that biological samples came from humans and not some other creature.
“It’s like a microcosm,” Sobolik says. “It’s a perfect sample. The DNA of the human and everything else preserves much better in paleofeces than in bone.”
Sobolik’s research focuses on the analysis of paleofeces, human skeletal material, and faunal and botanical remains from sites in the American Southwest and Maine. She has traded fieldwork for a bigger-picture view on archaeology, and she finds the advent of new technologies and methods exciting. They have raised fundamental questions and caused researchers to rethink some key findings.
“We’re reanalyzing some of our big ideas that we thought were a done deal,” she says. “I think this is the development of a new future.”
That is, a future steeped in the past.
For instance, in 1959, when Louis and Mary Leakey discovered hominid fossils at Olduvai Gorge in Africa, they spent countless hours mapping where rocks and bones were clustered, and they came to the conclusion that the remains they found were probably one of the earliest family units. Back then, taphonomy — the study of site formation processes and how they affect what, where and when things are preserved — wasn’t a huge concern.
Sobolik’s book underscores why taphonomy should be the first thing researchers consider before they start their fieldwork. Unlike Pompeii, where everything was entombed and preserved instantly in a thick coat of lava, most archaeological sites change over time due to a variety of factors.
In the case of Olduvai Gorge, researchers with a taphonomic viewpoint argue that the bones may not have been clustered together because they belonged to members of a family. The bones were found at the edge of Lake Turkana, and as the waters lapped the shore, they may have kept the remains together.
For anthropologists such as Sobolik, taphonomy and paleonutrition are intricately linked. If researchers don’t know why biological remains are in a site, then they don’t know whether there is relevant cultural context. That’s why the potential for the latest DNA technology is so exciting.
“Everything has to be reanalyzed. There’s so much to be done. We are learning with leaps and bounds what has happened with humans in the past,” Sobolik says.
Image Description: Mesquite (Prosopis sp.), a member of the bean family, was eaten by prehistoric peoples for thousands of years.