GSA Connects 2021 in Portland, Oregon

Paper No. 156-1
Presentation Time: 9:00 AM-1:00 PM


LABARGE, Thomas and NJAU, Jackson K., Department of Earth and Atmospheric Sciences, Indiana University, 1001 E. 10th St., Bloomington, IN 47405

Tooth marks in paleontological and zooarchaeological fossil assemblages represent a direct trace of consumer relationships in the past. However, the exact nature of the information stored within tooth marks remains poorly constrained. Taphonomic equifinality severely conflates mark morphology, often preventing accurate determination of the taphonomic agent. Without a robust framework for interpretation, studies are plagued by subjectivity, and many interpretations are not translatable across measurement techniques.

Actualistic experiments have attempted to constrain mark morphology against known taphonomic controls. These have been met with limited success and most conclusions are still accompanied by much uncertainty. Nevertheless, important strides have been made in defining both individual mark morphology and overall bone surface modification patterns. The contemporary view is that a wholistic evaluation of the entire assemblage is needed to clarify the interactions represented at a specific site.

Here we examine a sample of predator modified bones obtained from the controlled feeding of Nile Crocodiles (Crocodylus niloticus). Using a variety of measurement techniques, we assess whether certain aspects of mark morphology can be related unambiguously to tooth morphology.

These include a comparison of macro-, meso-, micro- and ultramicroscopic measurements of the bone surface. Marks are evaluated as both individual taphonomic traces and with respect to gross bite mark patterning across the skeleton. Moreover, we discuss the various limitations of each methodology to determine the most informative, efficient and cost-effective method of viewing bite marks.

We present various recommendations for extrapolating information from marks based on internal morphology and deformation properties. Additionally, we discuss issues arising among different samples and the efficacy of viewing cast material. It is our hope that with continued experimentation and reflection, a clearer method of bite mark description and identification can be developed.