One of the most complete fossilized dinosaurs ever found is revealing secrets locked away for millions of years, bringing researchers as close as they will ever get to touching a live dino.

The duckbilled hadrosaur is so well preserved that scientists have called it a "mummy." As a result they have been able to calculate its muscle mass and learn that it was more muscular than thought, probably giving it the ability to outrun predators such as Tyrannosaurus rex.

This rendering provided by the National Geographic Society shows the hadrosaur, nicknamed Dakota, as scientists believe it would have looked based on fossil evidence.
(National Geographic Society/Associated Press)

Although they call it a mummy, the dinosaur is not really preserved like King Tut was, as the body has been fossilized into stone. But unlike the collections of bones found in museums, this hadrosaur came complete with skin, ligaments, tendons and possibly some internal organs, according to researchers.

The study is not yet complete, but scientists have concluded that hadrosaurs were bigger — three tonnes and up to 12 metres long — and stronger than had been known. They were also quick and flexible and had skin with scales that may have been striped.

"It's unbelievable when you look at it for the first time," said paleontologist Phillip Manning of Manchester University in England. "There is depth and structure to the skin. The level of detail expressed in the skin is just breathtaking."

Manning said there is a pattern of banding to the larger and smaller scales on the skin. Because it has been fossilized, researchers do not know the skin colour, but looking at it in monochrome shows a striped pattern.

He notes that in modern reptiles, such a pattern is often associated with colour change.

A major discovery

The fossil was found in 1999 in North Dakota and now is nicknamed Dakota. It is being analyzed in the world's largest CT scanner, operated by the Boeing Co. The machine normally is used for space shuttle engines and other large objects. Researchers hope the technology will help them learn more about the fossilized insides of the creature.

"It's a definite case of 'watch this space,'" Manning said. "We are trying to be very conservative, very careful."

But they have learned enough so far to produce two books and a television program. The TV special, Dino Autopsy, will air on the National Geographic channel Dec. 9. National Geographic Society partly funded the research.

A children's book, DinoMummy: The Life, Death, and Discovery of Dakota, a Dinosaur From Hell Creek, goes on sale Tuesday and an adult book, Grave Secrets of Dinosaurs: Soft Tissues and Hard Science, will be available in January.

Soft parts of dead animals normally decompose rapidly after death. Because of the chemical conditions where this animal died, fossilization — replacement of tissues by minerals — took place faster than the decomposition, leaving mineralized portions of the tissue.

That does not mean DNA, the building blocks of life, can be recovered, Manning said. Some DNA has been recovered from frozen mammoths up to one million years old, he said. At the age of this dinosaur, 65 million to 67 million years old, "the chance of finding DNA is remote," he said.

Dinosaurs longer than thought

Matthew Carrano, a paleontologist at the Smithsonian's National Museum of Natural History, said he could not comment in detail about the find because he had not seen the research. But, he added, "Any time we can get a glimpse of the soft anatomy of a dinosaur, that's significant."

The findings from Dakota may cause museums to rethink their dinosaur displays. Most dinosaur skeletons in museums, for example, show the vertebrae right next to one another. The researchers looking at Dakota found a gap of about a centimetre between each one.

That indicates there may have been a disk or other material between them, allowing more flexibility and meaning the animals may actually be longer than shown in museums. On large animals, adding the space could make them a yard longer or more, Manning said.

Because ligaments and tendons were preserved, as well as other parts of Dakota, researchers could calculate its muscle mass, showing it was stronger and potentially faster than had been known.

They estimated the hadrosaur's top speed at about 45 km/h, about 16 km/h faster than the giant T. Rex is thought to have been able to run.