"What usually would have been wiped out by the decay process—the mineralization has been so rapid that it is trapped and preserved," Manning said.
"It's such a unique preservational environment here that we'll be able to say, Well, you basically need these conditions to mummify a dinosaur," Lyson, now a graduate student in geology at Yale University in New Haven, Connecticut, told a National Geographic reporter during a field trip to the excavation site.
"I think that's going to be pretty neat."
Big Rear, Fast Runner
Plant-eating hadrosaurs are often called the "cows of the Cretaceous"—the geologic period that spanned 145 million to 65 million years ago—Manning said. They had horny, toothless beaks but hundreds of teeth in their cheeks and a long, stiff tail that was likely used for balance. (Related: "Giant Duck-Billed Dino Unearthed in Utah" [October 3, 2007].)
Preliminary studies are revealing a surprising side to these reptiles, suggesting that Dakota—even though roughly 35 feet (12 meters) long and weighing some 3.5 tons—was no slowpoke.
With the aid of a large-scale CT scanner, the researchers determined how much muscle mass was packed between the bone and skin of Dakota's tail.
This allowed the researchers to infer the muscle mass of the dinosaur's rear end, which they calculated is about 25 percent larger than previously believed. A more muscular rear end means more powerful legs, Manning noted.
He plugged this new measurement into a computer model his team created to figure out how dinosaurs moved.
"Our models confirm this hadrosaur would have had potential to run faster than T. rex," Manning said.
The preliminary calculations suggest Dakota could run 28 miles (45 kilometers) an hour. Tyrannosaurus rex tops out at about 20 miles (32 kilometers) an hour, according to the model. (Related: T. Rex Quicker Than Fastest Humans, Study Says [August 23, 2007])
For Manning, the finding makes perfect sense. Hadrosaurs are believed to have been T. rex prey, so evolution would have favored a faster running speed.
"And that's what our initial findings support," he said.
John Hutchinson studies the movement of living and extinct animals at the University of London's Royal Veterinary College. He said caution is warranted for claims based on computer simulations, which he uses for his own work.
The margin of error for locomotion computer models can be greater than 50 percent, he noted—enough to wipe out the speed difference between a hadrosaur and a T. rex.
"Knowing the leg muscle mass would reduce at least one uncertainty," he commented via email. "That's progress, but there are still huge uncertainties left."
Showing Some Skin
Research into Dakota's fossilized skin is also yielding image-altering clues to how hadrosaurs may have appeared, Manning's team says.
Though the skin has lost its color, much of its texture is still intact, allowing scientists to map it in 3-D to see what Dakota might have looked like.
"There seems to be a variation in scale size that might possibly correlate—as it does in modern reptiles in many cases—with changes in color," Manning said.
"There seems to be striping patternations associated with joint areas on the arm," he added, "and there's interesting information we're looking at in the tail as well."
The 3-D preservation of the skin has also prompted the researchers to search for traces of unfossilized soft tissue in the hopes that it might yield protein.
This April, for example, two teams announced the successful extraction and analysis of collagen, a bone protein, from 68-million-year-old T. rex fossils. Those findings supported the hypothesis that modern birds are descended from dinosaurs.
Manning's team is currently unable to discuss specific findings, which are pending peer review for publication in a scientific journal.
But team member Roy Wogelius, a geochemist at the University of Manchester, said: "We have an array of chemical analysis techniques that we're applying to the organism—and not just to the skin."
Remains to Be Seen
Other experts remain tight-lipped about the potential of Dakota to yield similar information as the T. rex studies.
Mary Schweitzer, a North Carolina State University scientist who worked on one of those projects, declined to comment until formal publication.
And Peggy Ostrom, a zoologist at Michigan State University who also studies ancient proteins for clues to how organisms are related to each other, commented only in general terms.
"It's rare to find an articulated skeleton and even more so to find one with fossilized soft tissue," she wrote in an email.
"If such finds show extraordinary preservation, they tempt us to wonder about the possibility of finding [unfossilized] biomolecules that might be remnants of the ancient organism."
National Geographic News editor Blake de Pastino contributed to this story.
Free Email News Updates
Sign up for our Inside National Geographic newsletter. Every two weeks we'll send you our top stories and pictures (see sample).
SOURCES AND RELATED WEB SITES