Tooth marks on an Albertosaurus jaw favor a small raptor feeding on the much larger dinosaur’s carcass. The study offers the first reported evidence of dromaeosaurid feeding on a tyrannosaur, suggesting opportunistic scavenging. A very young Albertosaurus remains an alternative suspect, and the marks do not reveal the cause of death. A dinosaur weighing more than half a metric ton appears to have become a meal for a much smaller carnivore. Scratches on its jaw point toward a raptor feeding on the remains of an Albertosaurus, a relative of Tyrannosaurus rex. The fossil analysis, published in the Journal of Paleontology, was led by University of Alberta researcher Joshua Doyon. Coauthors include university paleontologist Philip Currie and Royal Tyrrell Museum researchers Caleb Brown and François Therrien. The team favors a small dromaeosaurid, the dinosaur group commonly called raptors, as the animal responsible. If that interpretation is correct, the specimen provides the first reported evidence of one feeding on a tyrannosaur. Scavenging is considered more likely than an attack on the living animal. Panel 1 contains a …