- WASHINGTON -- For more than
a century, the study of dinosaurs has been limited to fossilized bones.
Now, researchers have recovered 70-million-year-old soft tissue, including
what may be blood vessels and cells, from a Tyrannosaurus rex.
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- If scientists can isolate proteins from the material,
they may be able to learn new details of how dinosaurs lived, said lead
researcher Mary Higby Schweitzer of North Carolina State University.
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- "We're doing a lot of stuff in the lab right now
that looks promising,'' she said in a telephone interview. But, she said,
she does not know yet if scientists will be able to isolate dinosaur DNA
from the materials.
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- It was recovered dinosaur DNA - the blueprint for life
- that was featured in the fictional recreation of the ancient animals
in the book and film "Jurassic Park.''
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- The soft tissues were recovered from the thighbone of
a T. rex, known as MOR 1125, that was found in a sandstone formation in
Montana. The dinosaur was about 18 years old when it died.
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- The bone was broken when it was removed from the site.
Schweitzer and her colleagues then analyzed the material inside the bone.
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- "The vessels and contents are similar in all respects
to blood vessels recovered from ... ostrich bone,'' they reported in a
paper bring published Friday in the journal Science.
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- Because evidence has accumulated in recent years that
modern birds descended from dinosaurs, Schweitzer said she chose to compare
the dinosaur remains with those of an ostrich, the largest bird available.
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- Brooks Hanson, a deputy editor of Science, noted that
there are few examples of soft tissues, except for leaves or petrified
wood, that are preserved as fossils, just as there are few discoveries
of insects in amber or humans and mammoths in peat or ice.
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- Soft tissues are rare in older finds. "That's why
in a 70-million-year-old fossil it is so interesting,'' he said.
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- Matthew Carrano, curator of dinosaurs at the Smithsonian's
National Museum of Natural History, said the discovery was "pretty
exciting stuff.''
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- "You are actually getting into the small-scale biology
of the animal, which is something we rarely get the opportunity to look
at,'' said Carrano, who was not part of the research team.
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- In addition, he said, it is a huge opportunity to learn
more about how fossils are made, a process that is not fully understood.
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- Richard A. Hengst of Purdue University said the finding
"opens the door for research into the protein structure of ancient
organisms, if nothing else. While we think that nature is conservative
in how things are built, this gives scientists an opportunity to observe
this at the chemical and cellular level.'' Hengst was not part of the research
team.
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- John R. Horner of the Museum of the Rockies at Montana
State University, said the discovery is "a fantastic specimen,'' but
probably is not unique. Other researchers might find similarly preserved
soft tissues if they split open the bones in their collections, said Horner,
a co-author of the paper.
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- Most museums, he said, prefer to keep their specimens
intact.
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- Schweitzer said that after removing the minerals from
the specimen, the remaining tissues were soft and transparent and could
be manipulated with instruments.
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- The bone matrix was stretchy and flexible, she said.
Also, there were long structures like blood vessels. What appeared to be
individual cells were visible.
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- She did not know if they were blood cells. "They
are little round cells,'' Schweitzer said.
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- She likened the process to placing a chicken bone in
vinegar. The minerals will dissolve, leaving the soft tissues.
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- The research was funded by North Carolina State University
and grants from N. Myhrvold and the National Science Foundation.
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- © 2005 Star Tribune
- http://www.startribune.com/stories/1556/5310952.html
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