Tiny Raptor Traces on Albertosaurus Bones Spark Debate Over Prehistoric Feeding Behaviors

Newly examined fossil remains from a site near Drumheller, Alberta, have revealed bite marks on an Albertosaurus skeleton that could represent the first documented instance of a small theropod feeding on a large apex predator, or alternatively, a case of juvenile cannibalism among tyrannosaurids.

The specimen, discovered in the late 1990s but only recently re‑studied with high‑resolution imaging, shows a series of shallow, paired gouges on the femur and rib fragments. Researchers note that the spacing and curvature of the marks match the dentition of dromaeosaurids—small, bird‑like raptors that lived alongside the larger carnivores of the Late Cretaceous. If the marks indeed belong to a dromaeosaurid, it would provide concrete evidence that these smaller predators occasionally scavenged the carcasses of much larger contemporaries, a behavior inferred from isolated teeth but never directly observed.

However, the team also considered a second, more unsettling possibility: that the bite marks were inflicted by a juvenile Albertosaurus itself. Juvenile tyrannosaurids are known to have different dietary habits than their adult counterparts, and some paleontologists have suggested that cannibalism may have been a survival strategy during periods of scarcity. The size of the gouges could be consistent with a sub‑adult jaw, and the location of the marks—on relatively unprotected bone—might indicate a feeding attempt by a conspecific rather than a small raptor.

Both scenarios carry implications for how scientists understand predator–scavenger dynamics in Late Cretaceous ecosystems. A confirmed instance of a dromaeosaurid feeding on an Albertosaurus would underscore the complex food web that existed in the Belly River Group, where opportunistic scavengers could exploit the remains of the top hunters. Conversely, evidence of juvenile cannibalism would add to a growing body of data suggesting that tyrannosaurids, like many modern predators, engaged in intraspecific killing and feeding, perhaps as a means of establishing dominance or simply to secure a nutrient‑rich meal.

The findings, reported in a recent preprint and highlighted by science news outlet Phys.org, are prompting calls for further microscopic analysis and comparisons with bite‑mark databases from other sites. Researchers hope that additional specimens from the same formation might reveal patterns that clarify which hypothesis is more plausible. As the debate unfolds, the Drumheller discovery reminds the scientific community that even well‑studied dinosaurs can still surprise us with new behavioral insights.