Posted on 04/14/2007 10:18:48 PM PDT by NormsRevenge
WASHINGTON - Researchers have decoded proteins from a 68 million-year-old Tyrannosaurus rex, the oldest such material ever found. The unprecedented step, once thought impossible, adds new weight to the idea that today's birds are descendants of the mighty dinosaurs.
"The door just opens up to a whole avenue of research that involves anything extinct," said Matthew T. Carrano, curator of dinosaurs at the Smithsonian's National Museum of Natural History.
While dinosaur bones have long been studied, "it's always been assumed that preservation does not extend to the cellular or molecular level," said Mary Higby Schweitzer of North Carolina State University.
It had been thought that some proteins could last a million years or more, but not to the age of the dinosaurs, she said.
So, when she was able to recover soft tissue from a T. rex bone found in Montana in 2003 she was surprised, Schweitzer said.
And now, researchers led by John M. Asara of Beth Israel Deaconess Medical Center in Boston have been able to analyze proteins from that bone.
The genetic code that directs the development of living things is the DNA, but that is more fragile and they didn't find that.
"But proteins are coded from the DNA, they're kind of like first cousins," Schweitzer said
What Asara's team found was collagen, a type of fibrous connective tissue that is a major component of bone. And the closest match in creatures alive today was collagen from chicken bones.
Schweitzer and Asara report their findings in Friday's issue of the journal Science.
"Most people believe that birds evolved from dinosaurs, but that's all based on the architecture of the bones," said Asara. "This allows you to get the chance to say, 'Wait, they really are related because their sequences are related.' We didn't get enough sequences to definitively say that, but what sequences we got support that idea."
"The fact that we are getting proteins is very, very exciting," said John Horner of Montana State University and the Museum of the Rockies.
And, he added, it "changes the idea that birds and dinosaurs are related from a hypothesis to a theory."
To scientists that's a big deal.
In science, a hypothesis is an idea about something that seems probable, while a theory has been tested and is supported by evidence. Previously, the bird-dinosaur relationship was based on similarities in the shape of bones, now there is solid evidence of a relationship at the molecular level.
Horner, who found the bones studied by Schweitzer and Asara, said this is going to change the way paleontologists go about collecting specimens — they will now be looking for the best preserved items, often buried in sand or sandstone sediments.
This summer, he said, his museum is organizing nine different field crews involving more than 100 people to search for fossils in Montana and Mongolia.
Asara explained that he was working on a very refined form of mass spectrometry to help detect peptides — fragments of proteins — in tumors as part of cancer research.
In refining the technique, he had previously studied proteins from a mastodon, and when he heard of Schweitzer's finding soft tissues in a T. rex bone he decided to see if he could detect proteins there also.
He was able to identify seven different dinosaur proteins from the bone and compared them with proteins from living species. Three matched chickens, two matched several species including chickens, one matched a protein from a newt and the other from a frog.
Co-author Lewis Cantley of Harvard Medical School noted that this work is in its infancy, and when it is improved he expects to be able to isolate more proteins and seek more matches.
"Knowing how evolution occurred and how species evolved is a central question," Cantley said.
The Smithsonian's Carrano, who was not part of the research teams, said the report is an important confirmation of Schweitzer's techniques and shows that "the possibility of preservation is more than we had expected, and we can expect to see more in the future."
Matt Lamanna, a curator at the Carnegie Museum of Natural History in Pittsburgh, called the finding "another piece in the puzzle that shows beyond the shadow of a doubt that dinosaurs are related to birds." Lamanna was not part of the research team.
So, does all this mean that a T. rex would have tasted like chicken? The researchers admit, they don't know.
Both research teams were supported by the National Science Foundation and the David and Lucille Packard Foundation. Schweitzer had additional support from NASA and Asara had added support from the Paul F. Glenn Foundation.
Not ‘good enough’ to get hornswaggled, huh?
No, just simply not good enough to understand “rate of decay”.
Just this morning I was putting food in the bird feeder and was chased off by a velociwarbler.
Bah- VelociWarblers are nuttin to worry bout- That old saying about “Weeblers Warbler but they don’t fall down” is nonsense. Warblers are infact quite clumsy because of being pidgeon-toed- Just run in circles, you’ll be fine
What is unscientific about it?
You pathetic little groupie, speak on something you understand.
This is a late reply, but I just stumbled across some information on the existence of an air sac system similar to that in birds appearing in theropod dinosaurs. I'm flagellating myself for having missed this before!
Birds are unique among living vertebrates in possessing pneumaticity of the postcranial skeleton, with invasion of bone by the pulmonary air-sac system1, 2, 3, 4. The avian respiratory system includes high-compliance air sacs that ventilate a dorsally fixed, non-expanding parabronchial lung2, 3, 5, 6. Caudally positioned abdominal and thoracic air sacs are critical components of the avian aspiration pump, facilitating flow-through ventilation of the lung and near-constant airflow during both inspiration and expiration, highlighting a design optimized for efficient gas exchange2, 5, 6, 7, 8. Postcranial skeletal pneumaticity has also been reported in numerous extinct archosaurs including non-avian theropod dinosaurs and Archaeopteryx9, 10, 11, 12. However, the relationship between osseous pneumaticity and the evolution of the avian respiratory apparatus has long remained ambiguous. Here we report, on the basis of a comparative analysis of region-specific pneumaticity with extant birds, evidence for cervical and abdominal air-sac systems in non-avian theropods, along with thoracic skeletal prerequisites of an avian-style aspiration pump. The early acquisition of this system among theropods is demonstrated by examination of an exceptional new specimen of Majungatholus atopus, documenting these features in a taxon only distantly related to birds. Taken together, these specializations imply the existence of the basic avian pulmonary Bauplan in basal neotheropods, indicating that flow-through ventilation of the lung is not restricted to birds but is probably a general theropod characteristic.
O'Connor, P. M.; Claessens, L. P. A. M. "Basic avian pulmonary design and flow-through ventilation in non-avian theropod dinosaurs." Nature 2005, 436, 253.
You are quite a legend in your own mind.
Dinosaur protein sequenced - Lucky find shows up record-breaking fossil.
news@nature.com | 12 April 2007 | Heidi Ledford
Posted on 04/13/2007 6:14:00 PM EDT by neverdem
http://www.freerepublic.com/focus/f-news/1817005/posts
Ancient T. rex and mastodon protein fragments discovered, sequenced
National Science Foundation | 12-Apr-2007 | Cheryl Dybas
Posted on 04/12/2007 3:43:57 PM EDT by AdmSmith
http://www.freerepublic.com/focus/news/1816333/posts
BBC: Protein links T. rex to chickens ~ ummm tasty....
BBC | Thursday, 12 April 2007, 19:27 GMT 20:27 UK | Paul Rincon Science reporter, BBC News
Posted on 04/12/2007 4:57:11 PM EDT by Ernest_at_the_Beach
http://www.freerepublic.com/focus/f-news/1816370/posts
Scientists Retrieve Proteins From Dinosaur Bone
New York times | April 12, 2007 | JOHN NOBLE WILFORD
Posted on 04/12/2007 5:05:00 PM EDT by gcruse
http://www.freerepublic.com/focus/f-news/1816375/posts
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