A dinosaur footprint has been discovered that is causing some rethinking about how Dinosaurs walked. The article, in the L.A. Times by Thomas Maugh notes:
Steven Spielberg got it wrong. In his classic 1993 film "Jurassic Park," the director showed Tyrannosaurus rex, Velociraptor and other carnivorous dinosaurs walking with their forearms hanging down like a monkey's and their palms more or less parallel to the ground -- a posture derisively referred to by paleontologists as the "bunny position."
A growing body of evidence, however, has suggested that the creatures were physically unable to assume this position because their wrist bones would not turn in such a fashion.
Now, the first unequivocal handprint of a 198-million-year-old crouching carnivore confirms the speculation, providing clear evidence that the front limb struck the ground on its side, like a karate chop, and thus would have been of little use for walking.
This is cool. This is how science works. It is not that Spielberg didn't do his research, it is that he had the best information at the time. The author continues:
The extremely rare handprint from the St. George Dinosaur Discovery Site in Utah indicates that even early dinosaurs had forelimbs similar to those of birds, reinforcing the now widely held conclusion that birds are the only living descendant of the ancient monsters.
It is now thought that something like Eoraptor gave rise to the line that included birds.
"What this seems to imply is that, even from fairly early in their history, dinosaurs were entirely bipedal and weren't using their forearms to support themselves in any way," said paleontologist Tom Holtz of the University of Maryland, who was not involved in the research.