for National Geographic News
Soft-tissue dinosaur remains, first reported last year in a discovery that shocked the paleontological community, may not be all that rare, experts say.
A 2005 paper in the journal Science described what appeared to be flexible blood vessels, cells, and collagen-like bone matrix from fossils of a 70-million-year-old Tyrannosaurus rex.
Mary Schweitzer, the North Carolina State University paleontologist who announced the finding, said her team has now repeated that feat with more than a dozen other dinosaur specimens.
To make sense of the surprising discovery, scientists are beginning to rethink a long-standing model of how the fossilization process works.
Schweitzer gave an update of her team's progress unraveling this mystery last Friday at the annual meeting of the American Association for the Advancement of Science, held this year in St. Louis, Missouri.
Traditional ideas of how fossils form do not allow for the preservation of soft, perishable organic tissues.
"We propose now that soft-tissue components of bone might persist in a lot more different animals, in a lot more ages and environments, than we once thought," Schweitzer said.
"All we have to do is look."
Seek and Ye Shall Find
The researchers have applied their original technique of dissolving away the mineral content of bones and fossils to many different specimens, from contemporary to ancient.
Until now, Schweitzer said, "the standard wisdom was that if you dissolve away the mineral [in fossils], there would be nothing left." That has been the case in about half of the specimens she has examined.
But the other half have yielded remarkably consistent results.
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