New evidence backs up claim of dinosaur soft tissue find

In a new study, biochemist James San Antonio and colleagues offer evidence to support the claims by Mary Higby Schweitzer back in 2005, that she and her colleagues had unearthed a soft tissue specimen that belonged to a Tyrannosaurus rex. Roundly criticized by many in the science community, the specimen, discovered inside a femur fragment, has yet to be proven to be anything else. 

Tyrannosaurus rex femur (MOR 1125) from which demineralized matrix (insets; bars, 20 µm) and peptides were obtained ]Credit: PLoS ONE 6(6): e20381. doi:10.1371/journal.pone.0020381]
Now, in a paper published on PLoS ONE, San Antonio and his colleagues (including Mary Schweitzer) claim they’ve found a plausible explanation for the survival of soft dinosaur material after some 68 million years. 

The team focused on bits of collagen found in the remains, which are a group of proteins found in the flesh and bones of animals; it grows in a triple helix, which when it winds together, is known as a microfibril. When thousands of microfibril wind together, as they often do, they are known as microfibrils. 

After carefully studying 11 fragments of collagen recovered from the T. rex bone and then comparing them to similar fragments in modern rat and human collagen, the team discovered that the found fragments all came from the same innermost part of the fibrils that make up microfibrils. San Antononio likens them to tiny fibers that sit at the very innermost part of a very thick strong rope.
 

In their paper, the research team suggests that because they were so tightly wound, the microfibrils could have survived over millions of years. They also note that the specimens also contained very few amino acids, which are very susceptible to decay. 

To back up her claims, or to quiet the naysayers, Schweitzer points out that if the specimens found were actually contaminants from other more recent organisms, as some have claimed, there should have been more randomness to the collagen, instead of the strict uniformity that was found. She also notes that two other labs have corroborated her results. 

The unfortunate side story to all the research done so far though, including these latest findings, is that thus far there is no way to definitively prove whether the soft tissue found inside that T. rex bone was in fact a remnant from its original owner, or something that came after. Thus, claims from both those supporting the idea that dinosaur tissue could have survived for millions of years, and those that think it’s nonsense, are likely to continue. 

Author: Bob Yirka | Source: PhysOrg [June 15, 2011]