Researchers studying fossils from Spain have identified a prehistoric "bear-dog" that offers new clues about the evolution of some of the ancient world's leading predators. Recovered near Barcelona, the animal dates to about 15.9 million years ago and appears to rank among the earliest known members of its lineage. What happened? A team of paleontologists reported the discovery of a new amphicyonid species in Spain's Vallès-Penedès Basin, based …