Paleontologists and computer scientists joined forces to paint fossils with digital flesh and create dynamic models that reveal how dinosaurs may have looked, walked and attacked prey. Here the physical skull of Deinonychus, a meat-eating dinosaur, is placed inside a 3-D display and then augmented with reconstructed soft-tissues, including paranasal air sinuses and bony eye rings. Credit: Oliver Bimber, Bauhaus University, Germany; Stephen M. Gatesy, Brown University; Lawrence M. Witmer, Ohio University; Ramesh Raskar, Mitsubishi Electric Research Laboratories, Massachusetts; L. Miguel Encarnação, Fraunhofer Center for Research in Computer Graphics, Rhode Island

Video Researchers from Ohio and Texas used CAT scans to peer into the heads of two ancient flying reptiles called pterosaurs. This animation demonstrates the relationship of head orientation to the inclination of the lateral semicircular canals (shown in blue) of the pterosaur Anhanguera santanae. When the semicircular canals are brought to a normal, near-horizontal position, the long axis of the head turns downward, a position ideally suited for hunting in flight. Credit: Trent L. Schindler, National Science Foundation video  View Video Requires Real Player

Uncovering the bones of a dinosaur may be physically demanding, but it is by no means the end of the discovery process. Detailed analysis of the bones often requires years of painstaking effort or the development of new tools and techniques. Here are just a few examples of NSF's support for scientists taking a new look at old bones.

Oregon State University scientists studied a well-preserved fossil of a meat-eating dinosaur and found clues to a number of dinosaur debates. They suggested that, although dinosaurs were in fact cold-blooded, they could have bursts of high energy and speed. The same study concluded that birds are most likely not descended from any known family of dinosaurs.

Researchers from Ohio and Texas used CAT scans to peer into the skulls of two pterosaurs, flying reptiles that lived alongside dinosaurs. In their examinations of the passageways and chambers inside the skulls, they found key structures to be specialized and enlarged, a discovery that could revise views of how vision, flight and the brain itself evolved.

But old bones are not the only source of new information about dinosaurs. NSF has also supported studies of modern creatures that provide insights into dinosaur physiology and behavior.

Changing the nostril position in Tyrannosaurus rex affects how scientists understand the extinct creatures' respiratory functions. The traditional view (middle) has the nostril located more to the rear of the head. A new restoration (bottom) based on Lawrence Witmer's study reflects a more forward position of the nostril. The skull is shown at top. Credit: W. L. Parsons, under the direction of L. M. Witmer

For example, a study of skulls from more than 65 surviving dinosaur relatives—including crocodiles, birds and lizards—challenged the conventional view of dinosaur nostrils. Dinosaurs may have had larger nasal passages than had been thought, which could lead to greater understanding of their respiratory functions.

And a study of young birds provided a possible solution to the riddle of how full-fledged flight evolved. Based on videotapes of young birds flapping their way up ramps, University of Montana researcher Kenneth Dial proposed that two-legged dinosaurs may have used their forelimbs as wing-like structures to propel themselves rapidly up steep inclines.