More than a clay pot, more than a crumbling ancient building, a bone can sometimes speak to the secrets of history. Anthropologist Elizabeth Reitz has discovered that biological clues can help reveal what species of animals a population raised and ate, how their culture was inspired by food choices, and the technologies they developed to access different sources of nourishment. And, she says, bones can divulge even more.
"It seems to me a much more basic way of looking at the human past. One of the basics is diet. And often diet is associated with social status, and social structure. So you can go from how people used animals for food, into symbolism. We have a lot of intellectual and ideological components to the use of animals," she said.
Reitz, a AAAS fellow, is Professor of Anthropology at the University of Georgia in Athens. Her expertise is zooarchaeology, the study of faunal remains, including shells, bones, and DNA from archaeological sites. She realized early in her fieldwork that, for her, examining hundreds of potsherds simply did not spark the same intrigue that decoding one bone could.
"From one deer skull, you can often learn the age and sex of an animal, learn about population biology, herd structure and dynamics. And increasingly from genetic information, and the study of stable isotopes, we can learn the plants that made up the animals' diet, and about diseases," she said.
In recent decades, two new technologies, stable isotope analysis, and archaeogenetics, have helped scientists detect much more intricate details of ancient life. Stable isotope analysis compares the ratio of different carbon isotopes in bones. That can help determine dietary patterns, even the climate of the times.
"There have been profoundly revolutionary new perspectives. We can know so much more about what people did in the past," said Reitz.
For example, those tools, along with microbotanical studies, are helping scientists understand how Australian aborigines may have used fire 50,000 years ago to change their landscape. There's some evidence fire was used to improve forage for animals, and encourage the growth of the most useful plants.
And bones can do more. Researchers can also gain insight about culture and status by examining butcher marks and specific bones. Discovery of vertebrae with butcher marks would indicate a high status location, while animal feet would likely be a butchery location or a lower status or servants' household.
Reitz has worked throughout Latin America, the Caribbean, and the southeastern United States, studying vertebrate remains from coastal archaeological sites dating from the late Pleistocene era into the 20th century.
On one trip in Mexico, she learned that scientific knowledge can be deepened by collaborating with contemporary residents. Armed with a field guide to local birds, she was puzzled when her Mexican colleague was not relating to the pictures on the page. It was a completely different story when they spotted live animals.
"It had to be alive! His ability to identify the bird depended on what the bird was doing, where the bird was located, the call the bird was making. The pictures were not the birds And I realized it was a different way of perceiving. So I could extrapolate from the picture to the critter, but he knew a lot more about the critter than I did!" said Reitz.
Much of her work is done at the Museum of Natural History on campus. where she manages a skeletal collection of more than 4,200 modern vertebrate and invertebrate specimens from across the Southeast, and coastal waters. The collection ranges from fish found off Georgia's coast, to rat bones found in a South Carolina mansion. Rats indicate European contact, since they are not indigenous to this hemisphere, and would also indicate something of a trashy or latrine area of the city.
"Several years ago the American Association of Museums did a survey, showing Americans trusted museums more than any other source of information. That's a pretty significant burden," noted Reitz.
While a museum has to inform and even entertain visitors, those goals always have to heed scientific reality. "Trying to find that balance between clarity and accuracy and motivating people, it is a challenge," she said. Reitz often takes her cues from the public just outside her door.
Whether it is their reaction to a stuffed bear or a live snake, she says visitors to the museum, especially children, are completely candid: "My office is just around the corner from our exhibit area. I'm probably a better scholar by virtue of the fact that every day I hear kids and their parents out there," said Reitz.
She remembers what a big impression one ostrich skeleton made on a "Bird Day" event.
"I found that I could amuse the children by simply taking the leg bones of the ostrich and standing it next to them. It's bigger than the three-, four- and five-year-olds. I do think sometimes we try and make huge points, when the 'awe factor' comes from these little points," she said.
The UGA zooarchaeology collection provides the raw materials for hundreds of scientific projects and papers every year. And the selection of thought-provoking public exhibits could inspire a new generation of scholars.