New research points to when massive asteroid impact happened, and why only some animals survived.
The flying reptile was among hundreds of fossils recovered by police in 2013.
A fossil skull from a bird that lived in the time of dinosaurs sheds light on how the ancestors of modern birds escaped extinction.
The ancient dinosaur ancestor likely ate the newly described species by accident.
The new species unearthed in Patagonia belongs to a group called abelisaurids, which resembled tyrannosaurs with short, bumpy faces.
Finding suggests "megapredators" may have been more common in Mesozoic Era than previously thought.
Prehistoric remains also reveal signs of a particularly large predator.
Long legs didn't make the massive predators faster but helped save energy during the daily grind, new research suggests.
Fossil shows that miniature dinosaurs likely shared the earth with giants during the Mesozoic Era.
Corral Bluffs location contains fossils from a critical time in the evolution of mammals.