Warm-blooded velociraptors? Fossilized proteins unravel dinosaur mysteries.

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The laser of a Raman spectrometer shines on aTyrannosaurus rextooth, gathering data about the organic material still locked inside it.LINDSEY LEGER
▼ In the bowels of Yale University's Peabody Museum of Natural History, Jasmina Wiemann yanks open a drawer in a floor-to-ceiling specimen cabinet. She lifts out a wickedly sharp, sickle-shaped dinosaur claw, black as coal. "This is the type specimen ofDeinonychus—the basis for theVelociraptorin theJurassic Parkmovies," she says. The black color signals something just as striking. The fossil isn't just a mineral replica of the original claw. It is likely two-thirds dinosaur residue, Wiemann says. "I bet this specimen is maybe 70% organic material by volume—more than we'd think!"
That fossils can harbor organic matter isn't new. Whole fields of science have sprung up to decipher ancient DNA and intact proteins. But most researchers think that in fossils as old as theDeinonychusclaw, most of the useful sequences of those molecules have long vanished. Now, Wiemann and her Ph.D. adviser, Yale's Derek Briggs, have devised a way to extract information locked in degraded proteins, even in fossils hundreds of millions of years old. "This [kind of] molecular preservation is really common, and we just didn't know," Wiemann says.
She and Briggs have shown how, when conditions are right in the weeks and months after an animal dies, cellular proteins can react with lipids and sugars. The process transforms the proteins into a mix of hardy polymers that repel water, resist microbes, and are impervious to heat. The polymers are chemically similar to those formed when meat browns or toast burns—and they can apparently last for eons.
Other researchers have claimed to find intact proteins more than 100 million years ago, in the age of dinosaurs, but the field has remained skeptical of such ancient preservation. No one could explain how proteins managed to survive the degradations of time, says paleontologist Maria McNamara of University College Cork in Ireland. Wiemann "very nicely came up with this very, very clever mechanism" for how proteins could persist after all, in an altered form.
After a proof-of-principle paper last year, Wiemann and Briggs are applying their nondestructive technique—shining a laser on specimens to reveal ancient chemical bonds—to help solve paleontological mysteries. This week at a meeting in Australia, they planned to report how they used protein residue data to help resolve where turtles fit on the vertebrate family tree, and to support the idea that pterosaurs, the largest animals ever to fly, were warm-blooded.
The technique is new, so "it needs to be validated by more fossil and experimental work," McNamara says. And the method by itself can't resolve evolutionary puzzles with certainty. But she and others find the chemical mechanism convincing. "It's a completely new level of understanding of preservation. They are shedding light on the why and how," says Jingmai O'Connor, a paleontologist at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. "It's incredible how [Wiemann] is revolutionizing our field, opening so many new doors by applying chemistry to a field where chemistry has rarely been applied."
For Wiemann, the first clues to how biomolecules might persist for (▪ ▪ ▪)

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chanakyakripa

Great initiative. May open up a Pandora's box of ancient information, clues on not only ancient animals but also ancient human history. If this technique works on paleontological evidences, then why limit that to prehistoric animals and not on ancient human civilisation remains.