for National Geographic News
If you ever wanted to grow up to be a dinosaur hunter, now is the time to do it. Fossil finds and improvements in technology over the last decade have spurred stunning advances in the field, and there is no reason to think that the pace will slow anytime soon.
In the last couple of years, paleontologists have unearthed the biggest meat-eater ever (as yet unnamed, but pity poor T. rex, who is losing status fast); Paralititan stromeri, the second biggest dinosaur ever to walk the face of the Earth (think small building on legs); and Sarcosuchus imperator, a crocodilian who wanted to be a dinosaur, but didn't quite make the cut. On the other hand, he was the size of a large school bus with jaws long enough to accommodate your average NBA player.
The incredible advances in understanding can be divided down two linestechnology and available materials, said Mark Norell, chairman of the Division of Paleontology at the American Museum of Natural History.
"The technology is changing all the time," he said. "Today we can use CAT scans to look inside fossils, we can use computers to generate very detailed biomechanical models that can tell us things like range of motion and speed. Mass spectrometers can date fossils with a tremendous amount of precision, and we can use remote sensing and satellite imagery to narrow down the places where we look for fossils.
"The other thing is the phenomenal amount of spectacular fossils that have been found," he continued. "I don't think if anyone had told us ten years ago we'd be looking at the finds that have been uncovered in Argentina and Asiadinosaurs sitting on top of their nests, feathered dinosaursany of us would have believed it."
Reevaluating Dinosaur History
Up until the 1970s, scientists thought of dinosaurs as big, dumb, slow, and cold-bloodedessentially overgrown lizards. Today's explosion of interest had its genesis in the early 1970s when paleontologists John Ostrom and Bob Bakker made the case that dinosaurs were warm-blooded, active, and intelligent.
This radical reassessment has engaged paleontologists ever since. And who wouldn't be riveted by the questions that arise?
The globalization of fossil digs and a truly spectacular ratcheting up of technology since then has revealed a broadly diverse picture of dinosaurs that includes lots of small, dog- and turkey-size dinosaurs, as well as dinos that push the outer limits of what is physiologically possible in terms of size. In between is an array of evolutionary stops and starts; a banquet of possibilities in terms of filling specific ecological niches that includes huge size, small size; mouthfuls of weird teeth, partially formed beaks, frills, horns, and feathers.
Yes, feathers. It's more than possible that Tyrannosaurus rex, whose rep as a top-of-the-food chain vicious predator has made him an icon in the kingdom of Dinosauria, had feathersat least as a chick. The application of biomechanics to his physique shows that he wasnt very fast either. But more on that later.
Long Standing Uncertainties
SOURCES AND RELATED WEB SITES