Login Join | Donate | Annual Meeting | Career Center | SAA News | Marketplace | Contact   Search
 table of contents Minimize

 Chapter 2: The Science of Archaeology Minimize

Because archaeology is basically concerned with people, it forms an important subdivision of the social science of anthropology. Anthropology, the study of human culture, also includes three related specialties—linguistics, the study of human speech and language; physical anthropology, the study of the origins and biological evolution of humans as well as the patterns of human physical variation; and cultural anthropology, the study of living peoples and the great variety of their customs, adaptations, and achievements.

In practice, archaeologists utilize theories and methods of their colleagues in the other anthropological specialties and of experts in other fields of scientific study as well. Linguists, for example, can furnish useful checks on purely archaeological information. One of their techniques measures the change that has taken place between two related languages. Such change, say many linguists, is apparent when one compares lists of commonplace words, like "sky" or "mother," that nearly all peoples have in their vocabularies. By finding the degree of change in such word lists, the approximate time at which the two languages split from a common ancestral tongue may be indicated. Such data reinforce archaeological findings if they suggest a cultural divergence during the same span.

Physical anthropologists provide special knowledge about biological variation among modern humans and their ancestors. This includes not only the study of ancient human fossil remains in Africa, Asia, and other parts of the Old World but also skeletal remains in the Americas, where no forms of humans earlier than modern Homo sapiens are known. The study of such remains provides information ranging from ancient diet and disease to indications of intermarriage or the replacement of one population by another. New breakthroughs in the realms of genetics, blood chemistry, and dentition continue to open more and more paths to our knowledge of the past.

Cultural anthropology furnishes a wealth of knowledge on how living peoples use their environment, divide up labor, keep track of time, and organize themselves in households or social groups. If carefully applied, such information can provide useful analogies to help interpret the meanings of the material objects found in the ground.

Like modern settlements, the remains of past settlements—that is, archaeological sites—are all around us. Archaeologists are interested in knowing precisely where these sites are so they can be preserved and protected for study and for the benefit of future generations. The geographical relationships among archaeological sites, regardless of whether they were occupied at the same time or at different times, can themselves provide clues to how their inhabitants obtained food and other resources of the area. Relationships among sites occupied at the same time can indicate social, religious, and political links or conflicts that may have characterized the region.

One such regional investigation, by archaeologist Donna Roper, then of the University of Missouri at Columbia, concentrated on the Sangamon River Valley in central Illinois. Her thorough survey and sampling of the area brought two important periods of occupation to light: one between about 150 B.C. and A.D. 400, the other from around A.D. 400 to 700—periods that archaeologists, for convenient reference, have agreed to label respectively Middle Woodland and Late Woodland. From her work in the Sangamon Valley, Donna Roper found that during the earlier period people tended to locate their settlements away from the river, at the base of bluffs at the valley edge. These bluff-base settlements were located near water sources and other frequently used resources. During this early period, however, additional temporary camps were set up in the valley bottomlands to exploit aquatic resources and in locations farther afield to hunt deer. Settlements of the later time span were built in the bottomlands.

As Roper noted in her published report, these patterns were apparently the result of seasonal food procurement in the region—the reflection of a way of life similar to that of the Kickapoo Indians, who occupied the area in early historical times. According to eyewitness accounts in the historical documents, the Kickapoo shifted settlements with the seasons, practicing horticulture in one place during the summer, then moving into the bottomlands during the colder months to hunt.

Archaeologists often focus their investigations on a specific site—any area of ground once used, and thus modified, by human beings. There is no typical archaeological site. One may be a 10,000-year-old campsite such as that found at Debert, Nova Scotia, virtually indistinguishable on the surface from surrounding meadows and forest. Others might hold the crumbling buildings and refuse mounds of a great city like Chan Chan, Peru, or Baalbek, Lebanon. Whether cave or field, cliff dwelling or mound, or the stone foundations of a colonial house, each site is a unique and fragile remnant of the past. It holds not only artifacts but, more important, the sum total of existing clues on the relationship of these objects to one another. A site is a complicated package that, if carefully opened and meticulously recorded, can lead to interpretations of what happened at the place and provide information for determining when, how, and why it happened.

The decision to excavate can be based on many factors. Usually a particular problem—for example, when and why settled life began in an area—determines the choice. For the historical archaeologist, the reason for excavation may be to supplement or verify the written record, which is often plagued by omissions, biases, or vagueness. Excavations of settlements like Jamestown, Virginia, or the recovery of the cargo of a Civil War-period steamer provide glimpses of the past or, in the latter case, a past instant. And while historical records are of immense help in such cases, they may not address the specific archaeological problem involved.

In other cases, reservoir flooding or disturbance of the ground by highway construction, home building, or agriculture may threaten sites with destruction. Such circumstances dictate a program of conservation archaeology designed to protect as many sites as possible and to recover information that would otherwise be lost forever from sites that cannot be saved.

A good example of this is a site that once lay in an open pine grove at the tip of Rose Island in eastern Tennessee, near where the Tellico and Little Tennessee Rivers join. Knowing that Rose Island would soon be drowned by the new Tellico Reservoir, the Tennessee Valley Authority, in cooperation with the National Park Service, arranged for archaeologist Jefferson Chapman of the University of Tennessee at Knoxville to investigate Rose Island. His preliminary exploration showed that there was far more to Rose Island than first met the eye. Telltale bands of dark soil indicating successive human occupation appeared about six feet below the surface. The kinds of stone tools and the absence of pottery in these deep layers suggested that the site was quite old, occupied perhaps by wandering bands of hunter-gatherers.

Like all archaeologists, Jeff Chapman knew that in excavating he would necessarily destroy part of the site. Artifacts, of course, could easily be taken back to the laboratory for further study, but the all-important context of these remains could not be removed. Here is where Chapman's professional training came into play.

Because the location of everything found would have to be recorded in detail, he and his crew of students carefully laid a reference grid of numbered wooden stakes through the pine grove before removing the overburden of surface soil. For three months they carefully troweled in selected grid squares, peeling away the ancient deposits. As they progressed, layer by layer, they were careful to leave all artifacts within a layer—stone tools, chips, hearths, or whatever—in place until all could be carefully inspected, drawn, and photographed. Then they removed the artifacts to numbered bags before proceeding to the layer below. Dirt from each layer, meanwhile, was carefully screened to recover any artifacts or fragments that may have been missed. In addition, samples of soil were washed in a process known as flotation to separate out any seeds or plant remains.

As the pits deepened, the buried layers they had carefully removed could all be seen in cross section on the smooth walls of the pit. These were plotted to precise scale on graph paper.

By summer's end Chapman and his crew had recovered more than 40,000 items—including almost 30,000 tiny chips of stone, the residue of tool manufacture and use. These, however, were far less important than the thorough records the excavators compiled, for the records could now serve as a substitute for the excavated part of the site, telling people precisely where each piece had been found.

Back in the laboratory, analysis of the material began. Whereas it took Chapman only two summers to collect, record, and measure the archaeological data, it took years to accomplish the laboratory analysis, to formulate his conclusions, and to prepare the results for publication.

By using computers and special software developed for the purpose, thousands of stone lance points, other tools, and fragments were sorted according to diagnostic characteristics, or attributes. With the resulting classification, Chapman and his team were able to compare their findings with those from other sites and to estimate the time when Rose Island was first occupied.

The stone chips and their locations suggested not only how the tools were made but also where in the ancient camp the manufacturing went on. And burned acorns and hickory nuts gave valuable clues to the diet of the ancient Rose Islanders.

In the course of his analysis Chapman received useful aid from colleagues in other sciences. For example, technicians in physics subjected his charred wood remains to radiocarbon tests. Their dates—between 6100 and 7400 B.C., or early within the span that archaeologists call the Archaic—reinforced his preliminary dating of the main occupation of the site. This was refined even more by other specialists who, by observing the lineup of magnetic molecules in the Rose Island hearths, could estimate fairly closely how much time had elapsed between the use of successive fireplaces. A geologist well acquainted with the mineralogy of the area showed that the people of Rose Island had found flint nearby for their tools—one reason, perhaps, for using the site—while a specialist in botany used wood charcoal to identify oak, hickory, and other vegetation, all crucial clues to the ancient environment.

Had the excavation yielded other kinds of remains, the aid of still more specialists might have been sought: Malacologists, who study ancient and modern snail and other mollusk shells, and palynologists, who identify pollen, can help detect environmental changes through time; ichthyologists and zoologists identify fish and animal remains.

Just as was the case with Roper's work in the Sangamon Valley, the crucially important step of publishing the results of Chapman's work at Rose Island, now covered by the reservoir waters, was undertaken to ensure that the information would be available to everyone concerned with the human past. Equally important, following the recording and analysis, all the excavated artifacts, samples, field notes, maps, and other records were preserved so they will be available for future scientists to reanalyze with the greater knowledge and improved techniques and equipment of the future.

Jeff Chapman would be the first to acknowledge that Rose Island was no Tut's tomb, but he didn't care. In the vast sweep of the human past, the small Tennessee site is quite as essential a chapter as that provided us by the golden trappings of Egypt's pharaohs—and this is indeed what archaeology is all about.

Increasingly, archaeologists are turning not to sites but to the analysis of existing collections of artifacts or records of past surveys or excavations in order to gain information. With the growing recognition that it is often best to keep ancient sites intact for future generations, the study of collections, both institutional and private, is likely to become more common.

During the late 1960s, James Judge, then of the University of New Mexico, became interested in learning more about the life of the Paleo-indians, the earliest recognizable culture of the Americas—the Ice Age hunter-gatherers who lived in North America before about 8000 B.C. Judge was specifically interested in the Paleo-indians of the Central Rio Grande Valley, New Mexico. His first step was a survey of the area, much like that done by Donna Roper in Illinois. After recording the locations of sites that could be detected by surface evidence, Judge turned to existing collections from the area. The use of such material ultimately saved him an immense amount of time and effort in his analysis.

Using all these data, plus new information from sites he investigated himself, Judge sought the relationships between changes in Paleo-indian artifact forms, settlement location, and the environment over time. The analysis revealed that the then accepted view of Paleo-indian life in New Mexico as an unchanging span devoted to the hunting of big game was wrong. In its place emerged a picture of a long period in which patterns of animal watering places and human settlement, as well as the inventory of available animals, were in continuous change as the climate fluctuated and gradually became drier and as humans developed ways to organize themselves, to find and utilize resources, and to make a place for themselves in their world.

Archaeologists often deal with periods of time much greater than that embraced by Judge's work in New Mexico, for human or human-like beings have lived on earth for some five million years. However, far more than 99 percent of that enormous span lies totally out of reach of the earliest written records. When Columbus first set foot on what came to be called the Americas, people had inhabited those two vast continents for more than 13,000 years, yet virtually no decipherable written records were left. For any knowledge of our collective heritage, then, archaeology is the sole source of information.

For those who choose it as a career, archaeology can be even more intriguing than its popular image, and its personal rewards can far outweigh what are often challenging working and thinking conditions. There are many reasons that professional archaeologists enjoy what they do. Perhaps the best is the excitement of discovering some knowledge about ourselves that would otherwise remain out of reach. Likewise, nonprofessional avocational archaeologists can experience much the same challenge and thrill in knowing that they too can contribute to our knowledge of the human past. Neither can deny that there is much yet to learn.

To learn more about topics covered in Chapter 2 visit these National Park Service Features:

Ancient Architects of the Mississippi: Eight hundred years ago, the lower Mississippi Delta was home to some of the most highly organized civilizations in the world. This feature tells you about life along the Mississippi at that time, builders of great mounds, and the activities of travelers and traders. It also provides you with a myriad of voices about the Delta's past.

Submerged Archeology: Learn about the underwater projects of the Submerged Cultural Resources Unit, often in partnership with other organizations, including the U.S.S. Arizona and U.S.S. Utah at Pearl Harbor, ships and planes in Palau and Guam, and numerous historic shipwrecks in Dry Tortugas National Park and off Isle Royale National Park.

Archeological Research in the Parks: Many national parks have active archeological programs. Learn about the exciting results of archeological projects in some of your favorite parks by clicking on the state of your choice.

Kennewick Man: The human skeletal remains that have come to be referred to as the "Kennewick Man," or the "Ancient One," were found in July 1996, in Kennewick, Washington. Almost immediately controversy developed regarding who was responsible for determining what would be done with the remains. Claims were made by Indian tribes, local officials, and some members of the scientific community. The documents here provide background information and detailed reports of aspects of the work being done on Kennewick Man by the Department of the Interior.



Native American Petroglyph at Columbia River Gorge.

Emerald Mound National Historic Landmark in Natchez Trace Parkway.

An archaeologist looks over the results of the excavation.

Archaeologists in Jamestown, Virginia worked to locate the site of James Fort.

Workers from the Interagency archaeological salvage program race against time.

An archaeologist carefully screens dirt from excavation units to locate artifacts.

Archaeological storage at Anasazi Heritage Center.

Creating a map of the excavation site is essential due to the destructive nature of archaeology.

An archaeologist carefully unearths a prehistoric hearth in Alaska.

Detailed information about each artifact is recorded and preserved for future research or use in an exhibit.