Meeting Abstract

S3-5  Saturday, Jan. 4 10:30 - 11:00  Crushing and puncturing: biomechanics of tooth shape CROFTS, SB*; SMITH, SM; ANDERSON, PLS; CROFTS, Stephanie; UIUC; Field Museum of Natural History; UIUC; 1984; 1984; 1984

The tight relationship between tooth morphology and food material properties is often used to make inferences about an organism’s ecology and diet. Certain basic tooth shapes have been tightly tied to trade-offs associated with inducing fracture in different food items. For example, teeth used to puncture tough, deformable tissues can be modeled as relatively tall, narrow cones that balance tip sharpness with avoiding failure via buckling. Crushing teeth, alternatively, can be modeled as low rounded or flattened cones, which fracture brittle shells while resisting failure themselves. Simplified models such as these can be useful, but it is important to remember that teeth are more than simple cones. There are levels of complexity to tooth form and function, and secondary structures can be important to tooth function. The cusps of mammalian teeth are a well studied example of secondary tooth structures, whereas surface complexity and secondary structures occurring in non-mammalian taxa have been generally less studied. Ridges or edges, sharp raised features running from the tip of the tooth along the long axis, are one example of an easy to model secondary structure. Hypothesized purposes for these ridges include: reducing work to fracture, better gripping of food particles, and resisting biting stresses. Teeth used to cut tough materials, like skin and muscle, typically have bladed edges which serve to reduce required work. Similar but more numerous ridges occur in many tetrapods, and may be associated with durophagy and/or herbivory. Here we use biomechanical models to test hypotheses regarding ridge function under different loads, number and arrangement affect function, and how this interacts with overall tooth shape.