Using computers, scientists simulate movement of largest-known dinosaur


Using laser scanning and sophisticated computer modeling, scientists in England and Argentina have simulated the likely lumbering gait of the largest-known dinosaur, according to a new study.

“It’s really spectacular,” said Bill Sellers, a University of Manchester professor and lead researcher of the study published Wednesday in the journal PLOS ONE, which examines how and whether the enormous Argentinosaurus could have roamed the South American landscape more than 90 million years ago.

The Argentinosaurus was the largest of the sauropods, dinosaurs with long necks and tails, relatively small heads and thick, stout legs. It weighed more than 80 tons and was 100 feet long.

Given its massive size, there have long been questions about whether the dinosaur was as large as some experts suggested and how it physically could have moved such a titanic frame.

That uncertainly has persisted in part because so little of the Argentinosaurus has been recovered. Scientists have been left to deduce the size and mobility of the dinosaur based largely on a handful of vertebrae, ribs and leg fossils.

“It is frustrating there was so little of the original dinosaur fossilized, making any reconstruction difficult,” Phil Manning, who collaborated on the project and heads Manchester’s paleontology research group, said in a statement detailing the research.

To tackle that challenge, the researchers in Manchester and Argentina began by using a laser scanner to create a detailed, 3-D image of the dinosaur. They then used computer-modeling software designed by Sellers to reconstruct how the giant animal probably moved along the earth. The modeling took into account factors such as body mass, muscle size, and shape and bone structure.

“This is science, not just animation,” Manning said.

Their verdict: As far as the physics go, Argentinosaurus was a “perfectly competent dinosaur,” Sellers said. “There’s nothing mechanically that would stop you having an 80-ton dinosaur built like this,” which he said could have trudged across the landscape foraging vegetation on the ground or from the tops of trees.

But it wasn’t an easy existence.

“It was a relatively slow beast,” Sellers said, noting that the dinosaur’s top speed was probably about 5 mph. “As you get bigger, you start running out of the force you need to move. This animal would find things like getting up off the ground very difficult. I hate to think how it would do things like mate. That would be a very delicate operation for it, because it was so large.”

Sellers and his team are the latest in a long line of researchers, experts and animators who have tried to solve the riddle of how dinosaurs traversed the Earth.

Kent Stevens, a computer scientist and expert in dinosaur locomotion at the University of Oregon, said in a lecture last year that doing “good science” on the topic is difficult and tricky, mainly because researchers must figure out “a behavior that’s no longer observable” using mostly circumstantial evidence.

Sellers said he and his team tried to begin their undertaking with no preconceived notions and tried to rely only on the data available.

“The difference between what we’re doing and some other people are doing is that we don’t use as a starting point an assumed way that this animal would have moved,” he said. “We can’t be 100 percent certain that we found the best answer. . . . But we’re getting close.”

The Manchester team eventually plans to set its sights on detailing how smaller dinosaurs would have moved through the prehistoric world.

“Our next target is probably a triceratops,” Sellers said. “It has short front legs and long back legs. It’s going to have a really peculiar way of walking.”