Taxonomic distinctions in the 3D micromorphology of tooth marks with application to feeding traces from Middle Bed II, Olduvai Gorge, Tanzania
Date
2017
Authors
Muttart, Matthew V., author
Pante, Michael C., advisor
LaBelle, Jason, committee member
Boone, Randall, committee member
Journal Title
Journal ISSN
Volume Title
Abstract
Reconstructing the ecology of Early Stone Age archaeological sites is critical to understanding the conditions and behaviors that led to these accumulations, particularly as hominins encroached upon the larger carnivore guild by regularly consuming flesh and marrow from mammal carcasses; a dietary shift which is often considered a catalyst towards increased brain and body size. However, due to the paucity of both hominin and carnivore body fossils in the archaeological record, little is known about the specific carnivore taxa that hominins were competing and interacting with. The abundance of carnivore tooth marked bone at these early archaeological sites highlights the potential of these traces to help refine our knowledge of past hominin and carnivore interactions by linking specific carnivore taxa to the feeding traces found on fossil bones. This thesis seeks to determine if variations in a carnivore's tooth mark morphology can be used to differentiate between carnivore actors using feeding traces found in the archaeological record. Previous research seeking to link carnivores to their feeding traces have examined gross bone damage capabilities, gnawing damage patterns, and measurements of tooth pits from digital photographs. These findings have only been able to link body size of consumers to the levels of damage or size of tooth marks inflicted on bone surfaces during feeding. These findings are limited by the qualitative or two-dimensional analyses on which they are based, but highlight the potential for more advanced techniques of data collection and analysis. Controlled feeding experiments were conducted for seven species of modern mammalian carnivores and a single species of crocodile. Scans of individual tooth marks were produced using a Nanovea white-light confocal profilometer, while 3D models of the marks were analyzed with Digital Surf's Mountains Software. Tooth marks found on fossils from Middle Bed II, Olduvai Gorge, were scanned and compared against an actualistic sample of tooth marks. Quantitative analysis and statistical comparison of 3D measurements can be used to characterize taxonomic distinctions of tooth mark morphology between certain species as well as to link some fossil feeding traces to specific carnivore taxa. This method provides a means to identify specific carnivore actors from their feeding traces, potentially enhancing our ecological reconstructions of Early Stone Age archaeological sites and understanding of hominin-carnivore interactions as they relate to early hominin diet and behavior.