How Teeth Shed Light on Our Evolutionary Past

Presented by ANU College of Arts & Social Sciences, ANU College of Asia & the Pacific and ANU College of Health & Medicine

Teeth are some of the best preserved and most commonly-recovered elements in human fossil assemblages, leading to more than a century of comparative studies of tooth size and shape. Dental tissues also preserve remarkably faithful records of their development through time, represented by incremental features in enamel and dentine. Counts and measurements of these features have been used to determine the rate and duration of tooth formation, stress experienced during development, and the age at death in juveniles. A promising new area of incremental feature research is the application of virtual histology via synchrotron microtomography, which facilitates fine-scaled study of dental development in rare juvenile hominin fossils. Moreover, recent syntheses of tooth growth and chemistry allow insights into ancient migration patterns and dietary changes. Due to rapid technological developments in imaging and elemental sampling, these new approaches have the potential to increase our understanding of human developmental biology, including changes in the pace of growth and reproduction and the evolution of human weaning. The integration of these temporal, chemical, and structural approaches heralds a bright future for dental tissue research in evolutionary anthropology.

Dr Smith is an Associate Professor in the Australian Research Centre for Human Evolution at Griffith University. She has previously held a professorship at Harvard University and fellowships at the Radcliffe Institute for Advanced Study and the Max Planck Institute for Evolutionary Anthropology. She received her PhD in Anthropological Sciences from Stony Brook University in 2004. Dr Smith explores the evolution and development of the human dentition. Her research has helped to identify of the origins of a fundamental human adaptation: the costly yet advantageous shift from a “live fast and die young” strategy to the “live slow and grow old” strategy that has helped to make us one of the most successful mammals on the planet. Dr Smith’s research is funded by the National Science Foundation, the Leakey Foundation, and the Wenner-Gren Foundation for Anthropological Research. Her work has been published in Nature and Proceedings of the National Academy of Sciences, and highlighted in the New York Times, National Geographic, Nature, Science, Smithsonian, and Discovery magazines, as well as through NPR, PBS, History Channel, Voice of America and BBC broadcast media.