Fossils on File: Computerized Preservation May Give Reburied Bones Back to Science

Article excerpt

A human skull sits on a turntable, its eye sockets staring ahead impassively. Suddenly. the circular platform rotates slightly and stops, guided by a computer system set up on an adjacent desk. A laser beam strikes a point on the skull's temple, then jumps horizontally to a spot 1 millimeter away. The turntable shifts again and the thin shaft of laser light continues its millimeter-by-millimeter journey around the skull. Upon completing this circuit, the laser beam drops 1 millimeter and sets out over new terrain. No bony crevice or bump escapes its inquisitive ray.

Three hours and innumerable rotations of the turntable later, the laser has transferred exhaustive information on the skull's three-dimensional properties into the computer system. A highly accurate computerized tomography (CT) scanner fleshes out the specimen's interior features. Scientists then examine images of the skull and its various parts on the computer screen, print out detailed illustrations, and store precise measurements of the disembodied specimen for a comparative study of related finds.

Another computer-controlled laser then takes the anatomical data, capable of being stored on either a floppy disk or CD-ROM, and sculpts a precise nylon replica of the skull.

This unusual union of anthropology and advanced technology -- presided over by three researchers at the University of Texas at Austin -- may either invigorate the study of bones and cultural artifacts or prove too expensive to make a major impact. But its emergence within the past year suggests that scientific innovation sometimes feeds off anxiety. in this case sparked by new laws that allow Native American tribes to reclaim their ancestors' remains from museum collections.

"Our scanning and replication project may represent a compromise for what has become an almost intractable political problem," asserts John Kappelman, a Texas anthropologist who directs the project. "In many cases, we can noninvasively store data on bones and artifacts in the computer for generations to come and still honor the wishes and rights of Native American tribes."

The dilemma cited by Kappelman stems from a 1990 federal law, the Native American Graves Protection and Repatriation Act (NAGPRA), It requires federal agencies and museums that receive federal funds to inventory skeletal and cultural remains and return them to Native American groups that demonstrate a claim to the material. A number of tribes, both before and after passage of the legislation, have secured the return of museum-held bones belonging to their ancestors and cultural objects deemed sacred by their religious leaders, The skeletal material has invariably been reburied.

Many anthropologists and archaeologists rely on museum collections for research and regard the 1990 law as a potentially catastrophic blow to science, even if they accept it on moral grounds.

Enter Kappelman and his Texas coworkers, archaeologists Samuel Wilson and Thomas R. Hester. In March 1993, Kappelman convinced three Austin high-technology companies to participate in a project aimed at scanning and replicating a University of Texas collection of nearly 60 pieces of human bone, numerous pottery fragments, and assorted artifacts slated for eventual return to a Native American tribe.

Tribal leaders granted the scientists permission to study the 8,000-year-old remains.

Kappelman's team hit on the idea after experimenting with the technology in an analysis of several fossil knee joints that belonged to members of the earliest known species in the human evolutionary family. which lived in Africa more than 3 million years ago.

Austin firms dealing in cutting-edge computer applications gave the Native American project critical support. Digibotics allowed free access to its three-dimensional laser scanner, a technology already employed in the design, inspection, and animation of a variety of industrial products; Scientific Measurement Systems furnished its high-resolution CT scanner; and DTM Corp. …