Computers Show Triceratops Had Better Posture

W A S H I N G T O N,   May 24, 2001 -- Thanks to a computerized facelift, Triceratopsis looking good — for a 65-million-year-old.

The wraps come off today as the Smithsonian National Museumof Natural History returns the three-horned dinosaur to publicdisplay after more than two years being refurbished.

The new display, a full-size cast of the 23-foot-long animal,shows "how really easily Triceratops could do its job. … It justlooks like a very good animal that happens to have a whopping bighead," said museum paleontologist Ralph E. Chapman.

Dino Was Deteriorating

When it first went on display in 1905, the museum's Triceratopsmay have been the first horned dinosaur to be shown publicly. By1998 the fossilized bones were deteriorating, Chapman explained.

Not only did it need repairs, but over the years scientists hadlearned more about the dinosaur's posture, and they had realizedthat the original display contained bones from other animals.

It was time for some restoration.

Triceratops was a 5- to 6-ton plant eater and was one of thelast dinosaurs still alive before they all became extinct 65 million yearsago.

While the fossilized bones had lasted all that time in nature,the rigors of museum life — heat, cold, vibration, humidity — hadnot been kind. There were cracks, making them fragile, and pyritedisease, a condition in which the mineral pyrite begins growinginside the fossils and breaks them.

So the giant new skeleton going on display is a polymer casting.

Never fear, though, the real bones aren't hidden away.

The exhibit "is chock full of real material," Chapman said.It's just displayed in plexiglass cases to protect it from changesin heat and humidity.

"We put the real head out there and the real humeri [arm bones]and so forth," he said.

And what a head it is.

Apparently used for protection, and possibly fighting with eachother, the museum's Triceratops had a head that would have weighed700 pounds in real life. It displays two horns on top and a thirdon its nose, capping a powerful jaw.

They were plant eaters, "and boy, I'll tell you, they hadstrong jaws … they were overachievers when it came to chomping,"he said.

The animal's posture is also changed a bit, with its front legsslightly splayed.

It's what Chapman calls a "best guess" at how they looked.It's a guess that owes a lot to modern technology.

Computer Dino Construction

In the process of developing the new display, the bones werescanned with lasers so they could be reproduced with pinpointaccuracy.

Once the details were in a computer, the researchers used themto construct a one-sixth scale model — a more convenient size forthem to study.

When the skeleton was first displayed, the legs were shownwidely splayed, much like a lizard, Chapman said. But in the 1960sand '70s scientists decided the legs should be more straight up.

With the one-sixth scale model, Chapman and the otherresearchers could hold the bones in their hands and see how thejoints fit together. They worked out the new slightly splayedposture using rubber bands to simulate muscles and tendons andmanipulating the bones to see how each joint could move.

Essentially, they built the new Triceratops from the inside out,"letting the joint talk," he said. You couldn't do that with thefull-size bones, he added, or "you'd need a forklift."

The effort cost $2.2 million, all but $250,000 of which wasdonated, museum officials said.

Triceratops is on display across the aisle from the museum'sTyrannosaurus rex, a predator it may have encountered in real life.