Conducting an archaeological project in a cave has its pros and cons. On the one hand, artifacts are right out in the open, so no back-breaking digging is required. In addition, the constant humidity and temperature (about 54° F) and protection from the elements mean that archaeological remains in caves are exceptionally well preserved. On the down side, archaeologists have to work in almost complete darkness and in tight quarters. This activity is not recommended for the claustrophobic.
Washington University anthropology research associate George Crothers, Ph.D., must not be claustrophobic: He has spent the last seven years in Kentucky's dark, chilly Mammoth Cave, inventorying the contents of a three-mile portion of the cavern's 350-mile reach. The project has yielded a treasure trove of native American artifacts, from tools to textiles to pictographs and more.
Mammoth Cave, located in the south-central part of the state, is the longest cave system in the world. Native Americans explored and used the cave as early as 4,800 years ago. During the Early Woodland period -- 3,000 to 2,200 years ago -- they mined the cave for gypsum (perhaps to use as plaster or white paint) and mirabalite (known for its laxative effect).
"Many other caves were also entered and explored prehistorically -- hundreds by a conservative estimate," said Patty Jo Watson, Ph.D., the Edward Mallinckrodt Distinguished University Professor in Arts & Sciences and consultant on the project. "But the fairly intensive mineral mining in Mammoth and Salts Cave [also in Kentucky] is unusual. Most caves were probably used as mortuary places, or places to contact the supernatural world below the Earth's surface. Caves were special places for the prehistoric people who went into them. They did not enter the dark zone casually or in a workaday mode."
Mammoth Cave has been a national park since 1941, and the project has been conducted under the auspices of the National Park Service. Park managers had wanted to inventory the cave for some time. Robert Ward, park historian and co-principal investigator on the project, explained that by knowing what and where everything in the cave is, the park service is better able to preserve the cave's cultural and natural heritage.
Volunteers from Earthwatch, a nonprofit organization that connects amateur volunteers with scientific researchers all around the world, have provided key help.
"The stars really lined up for this project," Ward said. "We needed help, but we realized it would be very labor intensive and expensive. Hooking up with Earthwatch gave us a predictable way to do this project and provides us with a unique source of helpers."
Ward said working with Crothers is "one of the things that has made this project such a pleasure. He has a very dry, wry sense of humor, and yet he is very nurturing, supportive and collegial."
Crothers, also a co-principal investigator, has led the project for all but the first year. (Mary Kennedy, then a graduate student in anthropology here, first established it.) Charles Swedlund, of Southern Illinois University-Carbondale, is the third co-principal investigator.
The project's three-mile stretch, known as the Upper Trunk, is one of the largest and widest passageways and includes the only natural entrance used on cave tours. It is heavily traveled -- about 150,000 people visit annually.
Throughout the project, two crews of 10 Earthwatch vol-unteers work each summer and two more each fall for 10 days each. Each crew is divided into three groups. The first searches for artifacts, marking them with flags; the second group photographs, sketches and describes the items and their locations; and the last group uses a digital theodolite with infrared light to record the exact location of each artifact.
To date more than 8,000 artifacts have been documented. These include digging sticks, mussel shell scrapers, gourd containers, remnants from torches, cordage, twined slippers and fragments of other twined textiles which may have been pouches or bags.
Several pictographs also have been found. Most are simple geometric designs -- spirals, cross hatching and wavy lines. By far the largest artifact category is paleofeces, which have provided detailed information on ancient diet, including evidence that Native Americans were eating such domesticated plants as sunflower, sumpweed, goosefoot and maygrass. Hormonal analyses have been conducted on 12 paleofecal samples to determine the gender of the cave users -- all male so far. Efforts to recover DNA information are being undertaken now.
Work in the Upper Trunk will be finished this year or next. Then the systematic analysis starts. "All this data has been collected and compiled, but not edited yet," Crothers said.
The next stage will be time consuming. Ward said with only slight exaggeration that the team could be "crunching data now till the end of our lives."
Said Watson: "The quantity and quality of both historic and especially prehistoric material in the main tourist areas of the cave definitely surprised us. Because of the fine scale of the documentation and the long-term nature of the project, George is able to produce quite detailed maps of hundreds of items revealing distributional patterns that cannot be detected without just this kind of pain-staking, methodical recording."
