The near-complete remains may yield precious soft tissue, thanks to a technique that recovered structures resembling blood cells in a Tyrannosaurus rex skeleton last year.
"We've only been looking at one thing in the past, the dinosaur skeletal system, but we could learn so much more if we could study their circulatory system and other body systems," Vince Schneider, curator of paleontology at the museum, told Discovery News.
More than 80 percent of the Edmontosaurus annectens skeleton has been recovered so far, he said, and even more bones likely still exist at the Hell Creek site. The skeleton — missing only an arm, a few toes and a few other bones — is estimated to be among the top five percent most complete dinosaur specimens worldwide, said Schneider.
The large piece of fossilized skin once covered the adult dino's back right hip.
Julia Clarke, a North Carolina State University assistant professor of paleontology, worked on the dig. She told Discovery News that the skin is preserved in three dimensions, which is extremely rare.
"The skin appears to have internal structures inside of the scales," Clarke said. "These could be some kind of ligament attachments."
"A CAT scan of the skull, since it's so complete, could reveal the brain cavity, which could then tell us about the shape of its brain," said Richard Kissel, a dinosaur education specialist at the Field Museum in Chicago, who is not involved with the research. "It might then be determined how good the dinosaur's sense of smell and eyesight were."
While little is known about the prehistoric animal's life, the placement of the bones suggests how it died.
"It wound up in fine sandstone stream sediments," Schneider explained. "It probably drowned crossing at high flow. We haven't found any tooth marks yet suggesting a predator attack."
During the late Cretaceous period, said Schneider, this part of Montana was probably a large river delta that opened into an inland sea. Dinosaurs flourished there, as evidenced by numerous finds that have included T. Rex, Triceratops, and other types of dino fossils.
Evidence also suggests a lush forest with hardwood vegetation and leafy plants once stood there.
"The food supply must have been ample, since these dinosaurs ate a lot," Schneider said. "Our specimen, which would have measured about 24 feet long and was the size of a small elephant, probably weighed between one to two tons."
A near full skeleton.. and fossilized skin, rather nice.