rex share an evolutionary link and bolsters previous research showing that birds evolved from dinosaurs and that birds are living dinosaurs. This finding supports the idea that chickens and T. That's the Holy Grail," Schweitzer told LiveScience. "I'm grateful that he was able to get the sequences out. Amino acids are the molecular building blocks of proteins there are 20 of them used by organisms to build proteins, and their precise order is determined by instructions found in DNA.
rex collagen to a database of existing sequences from modern species showed it shared a remarkable similarity to that of chickens.
#TREX ARMS FOR CHICKENS SERIES#
Also, images from high-powered microscopes revealed a repeating series of thin stripes characteristic of collagen fibers.Īsara then ran the tiny samples through a mass spectrometer, a machine that measures mass and charge of individual molecules, finding the relic tissue was indeed collagen.Ī comparison by Asara's team of the amino-acid sequence from the T. To gather her evidence, Schweitzer ran chemical analyses, finding the tissue reacted with antibodies from collagen taken from chicken and other avian tissues. "For centuries it was believed that the process of fossilization destroyed any original material, consequently no one looked carefully at really old bones," Schweitzer said. So finding relatively intact soft tissue was a major claim. Usually, microbes devour all the easy-to-access soft tissue. The hard stuff of bones is all that usually remains when a dead organism is buried beneath layers of earth.
The finding made headlines, but was also questioned by some experts. In 2005, Schweitzer and her colleagues reported they had found evidence for soft, stretchy tissue sealed inside the dinosaur's fossilized femur. rex leg bone, which looks like a giant drumstick, was unearthed by Jack Horner of the Museum of the Rockies in 2003 in the Hell Creek Formation, a fossil-packed area that spans Montana, Wyoming and North and South Dakota. "It's not another molecule mimicking the protein and giving off a similar signal. If you're going to refute this you have to explain how these pieces got in there," Carrano said in a telephone interview. Matthew Carrano, a dinosaur curator at the Smithsonian Institution in Washington, D.C., who was not involved in either study, said the protein findings are robust. "It's very, very, very controversial because most people have gone on record saying there's an absolute time limit to anything that's protein or DNA," said Mary Schweitzer, a molecular paleontologist at North Carolina State University The new finding will be viewed skeptically, admitted one of the researchers involved in the two studies.
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