Next good dinosaur news likely to come from small packages

Dinosaurs seem bigger than life – big bones, big mysteries. So it's a delicious irony that the next big answers about dinosaurs may come from small – very small – remains.

"Molecules are fossils, too," said Michigan State University zoologist Peggy Ostrom. "We've shown that proteins survive in very old fossils, and proteins can tell us about diseases, about where prehistoric animals fit in the food chain, what they ate and who they are related to."

Ostrom joins six other scientists engaged in various versions of CSI: Jurassic Park. The symposium, "New Approaches to Paleontological Investigation," at the American Association for the Advancement of Science annual meeting Friday explores cutting edge technology used to divine new information from ancient bits of bone and tissue.

One of the field's hottest topics is whether proteins and DNA survive the test of time. Ostrom is putting her bet on proteins and is working with an international team from Michigan, the Smithsonian and York and Cardiff Universities in the UK to track down these building blocks of bone.

Ostrom works in a budding area known as paleoproteomics. Like conventional paleontologists, the search is to reveal the history of life on Earth. But tacking on proteomics means scrutinizing life at a molecular level – life that existed thousands of years ago.

Ostrom's work has spanned from examining organic matter in meteorites to reconstructing who eats who in the food web from the tropics to the arctic. The trail is laid by stubbornly durable molecules. She uses mass spectrometry, an analytical technique that determines what molecules are present.

Molecules may be tiny, but they can be tough, Ostrom said. The plant that a mastodon munched some 10,000 years ago disperses through the animal's body, sprinkling molecules of itself through tissue and hair -- vivid scientific evidence of the adage "you are what you eat."

"It just takes two or three pinches of bone powder to find molecular evidence," Ostrom said. "We have protein sequences from material believed to be in range of half a million years old. We are carefully working our way back in time."

She said it appears some proteins can endure longer than DNA. In a recent study Ostrom's students found that a protein in bone in an environment void of oxygen (say, if it's been resting in a swamp) can last for 200 hours at temperatures of 100 degrees Celsius.

"If we have a protein sequence from bone, we can tell if the material is an original part of the organism that will provide interesting information about its past. We can know where it came from." Ostrom said. "Our goal is to use a variety of technologies new to paleontology to develop a deeper understanding of prehistoric life -- and everyone dreams of embellishing our understanding of dinosaurs."

Source : Michigan State University