Posted on 04/12/2007 1:57:11 PM PDT by Ernest_at_the_Beach
By Paul Rincon
Science reporter, BBC News
Protein extracted from 68 million-year-old T. rex bones has shed new light on the evolutionary link between dinosaurs and birds.
Researchers compared organic molecules preserved in the T. rex fossils with those of living animals, and found they were similar to chicken protein.
The discovery of protein in dinosaur bones is a surprise - organic material was not thought to survive this long.
A US team of researchers have published the finding in Science journal.
The team says their technique could help reveal evolutionary relationships between other living and extinct organisms.
The finding is consistent with the idea that birds can trace a direct evolutionary line to dinosaurs.
The goal of obtaining sequences either from proteins or DNA for extinct [organisms] has been a long-standing goal 
Brooks Hanson, Science journal
The proteins are original organic material from the dinosaur's soft tissue, and not contamination, the scientists argue.
According to theories of fossilisation, original organic material is not thought to survive as long as this; finding them in a fossil this old is a genuine surprise. They are by far the oldest such molecules extracted from fossils.
"It has always been assumed that preservation of [dinosaur bones] does not extend to the cellular and molecular level," said co-author Mary Schweitzer, from North Carolina State University in Raleigh, US.
"The pathways of cellular decay are well known for modern organisms. And extrapolations predict that all organics are going to be gone completely in 100,000 years, maximum."
Brooks Hanson, an editor at Science journal said: "The goal of obtaining sequences either from proteins or DNA for extinct [organisms] has been a long-standing goal to test evolutionary links and processes, or even functional information."
The work builds on an earlier discovery of soft tissue - including blood vessels - by Dr Schweitzer's team in the same, incredibly well-preserved Tyrannosaurus rex fossils.
Exceptional preservation
The dinosaur remains - which include a skull, both thigh bones and both tibiae (shin bones) - were unearthed from rocks in the Hell Creek Formation of eastern Montana, US.
The fossils were buried under at least 1,000 cubic metres of loose sandstone, interspersed with muds, which are thought to represent ancient stream channel sediments.
The bones were buried under 1,000 cubic metres of rock in Montana
The proteins found in the T. rex bones belong to the elastic connective fibres - known as collagen - that support other tissues in the body.
Collagen makes up most of the organic material in bone, which consists of both minerals and protein. It is the same substance injected into the lips, and other areas of the body, in cosmetic surgery procedures.
When minerals are removed from human bone, a collagen matrix is left behind. The US scientists performed the same operation on the T.rex fossil, and found what appeared to be residual traces of collagen.
The findings of protein in the bones were confirmed by mass sepctrometry, a sensitive technique that identifies chemicals by their atomic mass.
It was able to show the T.rex material contained sequences of amino acids - protein building blocks - typical of collagen.
Chicken-like
When the scientists compared the protein sequence pattern to those of living animals in a database, it was found to be structurally similar to chicken collagen, and there were also similarities with frog and newt protein.
Dr Schweitzer said the similarity to chickens was exactly what one would expect given the relationship between modern birds and dinosaurs."
Dr Jack Horner, a co-author from the Museum of the Rockies in Bozeman, Montana, explained that extraordinarily well-preserved fossils such as the ones in question were probably not unique.
"To get specimens like that involves excavating enormous amounts of material, covered with tens of feet of rock," Dr Horner said.
"The T.rex was under a thousand cubic yards of rock and therefore in a position not to have been invaded by bacteria or groundwater," he said.
"I think we're learning an important lesson here - that if we do get specimens like this, we spend a lot of time getting as deep into the sediment as we can in places where there has been very little atmospheric or water contamination."
Dinosaurs, excluding bird lineages, disappeared from the face of the planet 65 million years ago. The reptiles are thought to have been killed off by an asteroid impact which struck off the present-day Yucatan peninsula in Mexico.
Pope Benedict ‘believes in evolution’
http://www.freerepublic.com/focus/f-news/1816636/posts
this one has lost his horn.
but this one seems to be intact.
Crikey!
No, it describes evolution. But by all means, please elaborate.
~grin~
Thank you.
Nothing specifically supports it.
~grin~
So I'm right then?
Good post.
The Gods must be crazy. :’)
Right about what, precisely?
Since T. Rex is now considered to be a type of chicken, does that mean they had feathers?
Maybe they're still big
but the rest of the cosmos
has gotten bigger!
““Evolution is a fairy tale for grownups.” Dr. Louis Bounoure, Director of the Zoological Museum and Director of Research at the National Center of Scientific Research in France”
I think you’ll find Bounoure did not say that, nor for that matter was he ever ‘Director of the Zoological Museum and Director of Research at the National Center of Scientific Research in France’ nor was he even a member.
He was a professor of biology at the University of Strasbourg.
Jean Rostand’s actual quotation was “Transformism is a fairy tale for adults.” and is actually a rebuttal of Lamarkian evolution (traits aquired during a organisms lifetime are passed as genetic legacy to the offspring)of which Transformism is a cornerstone.
Why if you feel the case againsts evolution is so strong do you feel the need to fabricate quotations and attribute them to whomsoever you feel best supports your cause?
I was being sarcastic.
There's a Helen Thomas joke in there somewhere...
Except you didn’t provide source at all for the Bounoure quote, which is understandable since there is no direct source for this statement from him.
What you actually provide source for is Jean Rostand whose precise quotation is as follows: “Transformism is a fairy tale for adults.” (Age Nouveau, [a French periodical] February 1959, p. 12).
And what do you know a search of the CRNS website (http://www.cnrs.fr/index.html)reveals no mention of Bounoure rather stange if he was once head honco don’t you think?
and here is a list of the Director Generals:
Jean Coulomb : 1957-1962
Hubert Curien : 1969-1973
Robert Chabbal : 1976-1980
François Kourilsky : 1988 - 1994
Guy Aubert : 1994 - 1997
Catherine Bréchignac : 1997 - 2000
Geneviève Berger : 2000 - 2003
Bernard Larrouturou : 2003- 2006
Arnold Migus : 2006-
Bounoure is rather conspicuous by his absence, what?
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