Bite and tooth marks on sauropod dinosaurs from the Morrison Formation

Area of Science:

• Paleontology
• Vertebrate Paleontology
• Dinosaur Paleontology

Background:

• Tooth-marked bones are key indicators of feeding behaviors in extinct carnivores.
• While tyrannosaur bite traces are well-documented, those of other large theropods are less understood.

Purpose of the Study:

• To investigate bite traces on sauropod bones from the Morrison Formation attributed to non-tyrannosaur theropods.
• To understand the feeding ecology of theropods in this Late Jurassic ecosystem.

Main Methods:

• Extensive survey of scientific literature and fossil collections.
• Cataloging and analysis of 68 sauropod bones from the Morrison Formation bearing theropod bite traces.
• Examination of bite mark characteristics and evidence of healing.

Main Results:

• A significant number of sauropod bones exhibit bite traces attributable to theropods, though less common than in tyrannosaur-dominated faunas.
• None of the observed bite traces showed evidence of healing, indicating perimortem or postmortem activity.
• Tooth wear in non-tyrannosaur theropods confirms bone-biting behavior.

Conclusions:

• Theropods in the Morrison Formation, including non-tyrannosaurs, actively engaged in bone-biting.
• The absence of healed bite marks suggests preferential predation on juvenile sauropods and scavenging of larger carcasses.