Advanced technology is helping scientists learn more about the nuts and bolts of extinct creatures like dinosaurs, says an expert from the University of Texas, Austin.

Prof. John Kappelman of that university's anthropology department added that computerized paleontology has gone beyond the laboratory, moving into the classroom.Kappelman spoke Tuesday during the opening session of the Society of Vertebrate Paleontology's annual meeting, which continues through Saturday at Snowbird. The gathering has drawn hundreds of paleontologists from around the world.

The University of Texas has acquired an industrial-power CT scanner capable of high resolution scans, Kappelman said. It is used for all sorts of projects, including engineering and paleontology. The device can provide views inside fossils that are ten times as detailed as available through conventional medical CT scanning.

After the scans are made, computers can assemble them into three-dimensional representations. Then researchers can view fossil skeletons reassembled from fragments, and use a mouse to rotate them.

According to Kappelman, the high-resolution CT scanner can make close-up views of the interior structure of bones. Researchers then analyze them for clues about such things as how much of a load different sections of bone could take.

The bones of animals that jump a lot will have a different morphology than those of creatures that are less active.

Also, he said, computer-generated images can be used to show how muscles moved bones or how a dinosaur walked. For a jaw muscle that is behind the lower jawbone, he showed how the computer-generated jaw can be turned to glass, allowing students to see the muscle's work as the jaw moves.

These images are compelling and bring extinct creatures to life for the viewer.

"It provides us with a mechanism by which we can introduce many more children, grade-school kids on up, to this field," Kappelman said of computers.

With the support of the National Science Foundation, "we've been designing a virtual, multimedia exam," he added.

A student uses a computer to take the exam. The program can ask a question about an ancient skull and jog the student's memory by showing a three-dimensional rotation of the skull. As the student progresses through the exam, the computer is keeping track of the right and wrong answers.

"The very last screen is the grade," Kappelman said. "You don't have to sit down and grade this stuff."

Ralph Chapman of the Smithsonian Institution, Washington, D.C., said computers can be used to fill in the missing pieces in fossils. This is possible because vertebrates are bilaterally symmetrical - that is, the left sides of their skeletons are mirror images of the right sides, including the sides of the skull.

For example, an ancient human skeleton may be missing the right leg bone, he said. "Let's model the left femur and mirror it, and prototype it - and bing!" he exclaimed. The recreated bone can be studied in computer 3-D images, or a physical copy can be made for display purposes, using a process called reverse engineering.

With reverse engineering, lasers are used to harden a matrix according to three-dimensional information stored in a computer. It can create an exact copy of a plastic pipe joint or a hominid skull.

"There are a bunch of different ways to get 3-D data in," he added. The information can go into the computer by using relatively crude and inexpensive devices like an armature that traces the bone or laser scanners and CT imagery.

Once the information is in the computer it can be used for many different studies.

"I think one of the most exciting things we can go into is functional analyses," he said. Scientists can see how bones had to work together and discover a dinosaur's range of movements. Computerized movies can be generated showing how a long-extinct creature walked.

"At the Smithsonian, hopefully we'll be building a virtual triceratops with our specimen," he added.

Fossils often are deformed by tons of earth and rocks pressing on them for millions of years. But using computers, they can be "undeformed," Chapman said. The scientists just need to figure out a mathematical formula to describe the forces that deformed the bones.

Some fossils are so fragile they are damaged when casts are made. But a virtual cast, created by computerized scanning, won't harm the original specimen and will allow an accurate recreation of the bone.

Likewise, he said, powerful CT devices can find the fossils within a matrix without anyone having to chip them out. Then the fossils can be assembled by computer and the casts or images studied.