Carnivores: Devouring Herbivores—and Each Other

Source Institution: Smithsonian National Museum of Natural History

Source Exhibit: David H. Koch Hall of Fossils - Deep Time

Source Url: https://naturalhistory.si.edu/visit/virtual-tour/current-exhibits/deep-time-virtual-tour-fossil-list

Source Kind: interpretive_topic_or_panel

Use: research inspiration only; SAGE will write original interpretation

Dossier Status: scientifically_enriched_concept_room_08

Plain Language Explanation: Carnivore diets can sometimes be reconstructed directly from damage left on fossil bones. Tyrannosaur tooth marks occur on herbivorous dinosaurs, while other fossils preserve tooth marks on Tyrannosaurus bones themselves. Because Tyrannosaurus was the only giant theropod in these latest Cretaceous communities, several such marks have been interpreted as evidence that T. rex sometimes fed on members of its own species.

Evidence: Large gouges and scores on dinosaur bones can be matched to tyrannosaur-style teeth.; Multiple Tyrannosaurus bones preserve bite marks interpreted as feeding traces made by other Tyrannosaurus individuals.; Tyrannosaur tooth marks do not automatically distinguish whether prey was killed or scavenged after death.

Examples From Collection: Tyrannosaurus rex tooth; Ceratopsidae indet. tooth; The T. rex and Triceratops centerpiece illustrates feeding ecology but is not itself direct bite-trace evidence.

Feeding Vs Killing Guard: A feeding trace establishes consumption more directly than it establishes active killing. Scavenging remains possible unless survival injuries or other evidence indicate attack on a living animal.

Common Misconception: Cannibalism does not mean Tyrannosaurus routinely hunted members of its own species. The fossils establish feeding on conspecific remains, while the circumstances of death usually remain unknown.

What Scientists Still Debate: The frequency of cannibalism, scavenging and active predation cannot be calculated precisely from the small number of feeding traces that happen to fossilize.

Sources: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0013419; https://www.si.edu/newsdesk/factsheets/tyrannosaurus-rex; https://naturalhistory.si.edu/explore/dinosaurs-fossils/nations-t-rex

Enrichment Method: SAGE original interpretive concept; direct Hell Creek fossil evidence separated from feeding inference, paleoart and museum reconstruction