Abstract
Modification to skeletal remains can be antemortem, perimortem, and postmortem in nature. Of these three, perimortem and postmortem modification can be the most difficult to differentiate between and also the most crucial informants of a medicolegal death investigation as they provide insight into the events that have occurred at the time of death up to the discovery and recovery of a decedent. The science of forensic taphonomy exists to understand, analyze, and interpret these modifications made to remains to establish events within the postmortem interval and to assist and inform the processes of scene investigation and remains recovery. The scavenging of remains by nonhuman actors leaves behind toothmarks and similar modifications on bone and are of great interest to forensic taphonomists. This thesis investigates if modern three-dimensional scanning technology can be used to differentiate forensically significant nonhuman scavengers to a more meaning level of taphonomic identification than previously seen based off of the dental morphology of these species. The objective of this thesis was to test if three-dimensional scanning technology and geometric statistics are currently at a level that can reliably differentiate the toothmarks of different taxonomic families, and potentially members of the same family but different genera, from one another. Additionally, this thesis focuses on species of forensic significance rather than species that may modify or cache bones more, but have little use in forensic comparisons such as hyenids or large African felids. I predicted that members of different taxonomic families can be differentiated from one another, as can members of the same family but different genera. I conducted statistical analyses to test these hypotheses using technologies and methods similar to those used in Courtenay et al. (2019), Courtenay et al. (2020), and Jiménez-García et al. (2020). Specifically, I sourced skeletal samples from the nonhuman skeletal collection curated and maintained by the Human Identification and Trauma Analysis program at Florida Gulf Coast University. Crania from the following species were analyzed for this thesis based on their presence in literature as species of forensic significance; wild/domesticated boar (Sus scrofa/Sus scrofa domesticus), domesticated cat (Felis catus), bobcat (Lynx rufus), domesticated dog (Canis familiaris), American black bear (Ursus americanus), North American river otter (Lontra canadensis), Virginia opossum (Didelphis virginiana), raccoon (Procyon lotor), white-tailed deer (Odocoileus virginianus), American alligator (Alligator mississippiensis), black vulture (Coragyps atratus), and several species of rodent. Full maxillary and mandibular profiles were scanned by the FARO design ScanArm three-dimensional scanner and rendered within the FARO RevEng 2020 software as a point cloud. Point clouds were then compared within the Cloud Compare v.2.12.4 software using the Multiscale Model to Model Cloud Comparison (M3C2) geometric statistical analysis for significant change in geometry against a 95% confidence interval.