The goal of this study is to explore the evolution of selachian (shark) teeth in the context of functional morphology. While asking how shark teeth work seems like a simple question with a simple answer (they cut, slice, tear, etc.), the issue is complicated by morphology. Sharks display a variety of tooth morphologies; presumably, different forms should have different functions. To quantitatively approach this issue, I subjecting shark teeth to performance testing on a variety of prey items to determine how teeth perform in puncture and tearing. This will be done using a MTS MiniBionixII universal testing system.

When you apply the question of tooth function to fossil sharks, the problem becomes even more complex, as teeth are often the only part that fossilizes. Very little is known about diet or the rest of the feeding appartus in extinct species, unlike thier extant cousins. In addition many morphologies seen in fossil shark teeth do not exist in modern sharks. Paleontologists must reconstruct the entire life history and anatomy of a species based on little information. I am using a model based approach (finite element analysis - FEA) where I can look at the stress distributions within the tooth when different loads are applied, simulating different prey items. An example of an FE model can be seen above. The cladodont tooth shown is loaded on the side of the cusp to simulate lateral movements of the head. Blue indicates low stress, while red indicates areas of high stress, or stress concentrations.