X-Rays to Scan Ancient Skeletons

The same kind of three-dimensional X-ray equipment that helps save human lives will soon be used to take pictures of prehistoric Indian skeletons.

Using computerized tomography, or CT, scans, imaging experts hope to develop an electronic archive that eventually could contain 3-D pictures of thousands of skulls and bones currently housed in museums and research centers worldwide.

There is an urgency to the project. Backed by a new federal law, many American Indian tribes are pressing museums and universities to return skeletons and sacred objects to them.

Scientists would like to record meaningful samples of the remains and extract as much information as possible from them before they are given back to the tribes for burial or ritual cremation.

“The X-ray technique known as CT may be the key to a vast electronic museum containing detailed visual information on prehistoric skeletal remains that could be transmitted to scientists around the world,” said Walter C. Hartwig, a University of California anthropologist who is here working on the imaging project.

Hartwig envisions a system that someday would enable scientists to call up detailed 3-D images of prehistoric skeletal remains from the electronic museum and study them on computers in their offices or laboratories.

“The material, of course, wouldn’t be limited to American Indian remains but could include rare fossil materials from many parts of the world,” he said.

Developed about 20 years ago, CT scanners convert X-ray pictures into digital computer code to make high-resolution video and computer images. With the computer’s capacity to manage information, CT can zoom in and scan the anatomy, yielding vivid and precise 3-D views that can be preserved in software for transmittal to personal computers.

Depicting bone structures in fine detail, CT scans can show small differences between normal and abnormal tissues in the brain, lungs and other organs.

“The imaging also gives the option for careful anatomical studies inside human skeletal remains,” said Donald J. Ortner, chairman of the anthropology department at the Smithsonian Institution in Washington. “You could study a whole series of measurements and dimensions inside the skull that have been virtually inaccessible to anatomists and physical anthropologists for a long time.”

Hartwig cautions that the bone “museum” is a long-term project “rather than something we would hope to establish within the next two or three years.”

Some of the first remains may come from the Lowie Museum of Anthropology at UC Berkeley. “We’d like to do a small sampling of remains from that collection for our prototype, perhaps the skulls of 10 to 15 individuals,” said Dr. Robert C. Taylor of the university’s medical school in San Francisco, who will do the project’s CT scans.

Working with Taylor and William A. Hanson of IBM’s Palo Alto, Calif., Scientific Research Center, Hartwig hopes that a simulation of the system will be ready to show museums and universities early next year.

“CT offers tremendous potential for capturing detailed information on our collections,” said Douglas H. Ubelaker, curator of anthropology at the Smithsonian. “We realize that we have a limited time, but we’d like to document our material as thoroughly as we can for future scholars and the Indians themselves.”

The Smithsonian’s collection of 18,600 Indian skeletons is the largest in the country. More than 2,000 skeletons already have been returned for reburial, and eventually all the bones may be repatriated.

Some remains soon will be returned to the Wichita tribe in Anadarko, Okla., for reburial. Tribal leaders say they would be receptive to 3-D imaging. “I see nothing wrong with this technology,” said Virgil H. Swift, a tribal historian. “Such a record of our ancestors might someday prove useful.”

Other Indians are not so receptive.

“Any disturbance of Indian remains, even with non-destructive X-rays, would be objectionable to the Pawnee Indians of Oklahoma,” said Robert M. Peregoy, a senior staff attorney for the Native American Rights Fund in Boulder, Colo.

But images of bones and skulls could tell scientists a lot about such things as growth patterns, infectious diseases and dietary habits of prehistoric Indians. Bone malformations in the skulls of small children, for example, can indicate anemia.

Even anthropologists who are enthusiastic about 3-D imaging do not see it as a panacea. “The imaging should not be envisioned as a way to replicate original material,” Ubelaker said. “Rather, I see it as a useful measure to augment existing efforts to salvage as much as possible before materials are irretrievable.”