Fossil showing Epidexipteryx, the pigeon-sized feathered dinosaur that lived 168-152 million years ago. Its long tail feathers, shown at bottom right, were most likely used for display. Fucheng Zhang

Paleontologists have long debated the function of the strange, bony crests on the heads of the duck-billed dinosaurs known as lambeosaurs. The structures contain incredibly long, convoluted nasal passages that loop up over the tops of their skulls.

Dinosaurs survived two mass extinctions and 50 million years before taking over the world and dominating ecosystems, according to new research published this week.

The remains of a new 10-meter-long predatory dinosaur discovered along the banks of Argentina's Rio Colorado is helping to unravel how birds evolved their unusual breathing system.

An unusual breed of dinosaur that was the size of a chicken, ran on two legs and scoured the ancient forest floor for termites is the smallest dinosaur species found in North America, according to a University of Calgary researcher who analyzed bones found during the excavation of an ancient bone bed near Red Deer, Alberta.

With long limbs and a soft body, the duck-billed hadrosaur had few defenses against predators such as tyrannosaurs. But new research on the bones of this plant-eating dinosaur suggests that it had at least one advantage: It grew to adulthood much faster than its predators, giving it superiority in size.

Paleontologists in 2005 hailed research that apparently showed that soft, pliable tissues had been recovered from dissolved dinosaur bones, a major finding that would substantially widen the known range of preserved biomolecules.

A new paper by Roger Benson of Cambridge University and colleagues discuss the taxonomic status of Megalosaurus bucklandii.

A Megaraptor-like theropod (Dinosauria: Tetanurae) in Australia: support for faunal exchange across eastern and western Gondwana in the Mid-Cretaceous. 2008. N. smith et al. Proc Royal Soc. B.

A partial dinosaur skeleton unearthed in 1971 from a remote British Columbia site is the first ever found in Canadian mountains and may represent a new species, according to a recent examination by a University of Alberta researcher.

Scientists who dig dinosaurs in Eastern Montana will now be able to chemically analyze fossils the same day they're excavated and before degrading begins.

Scientists have put more meat on the theory that dinosaurs' closest living relatives are modern-day birds.