During September's GC Skeptics in the Pub, Professor Tanya Smith talked about her archaeological research into using fossilised teeth to understand aspects of ancient development, evolution, and behaviour. From the first Neanderthal remains found in Germany's Neander Valley in 1856 to the recent discovery of fossilised Neanderthal footprints on a Normandy beach, Professor Smith's research paints an increasingly detailed picture of the life and development of Homo neanderthalensis, our 'closest evolutionary cousins'.
Homo sapiens and Homo neanderthalensis evolved from common ancestors such as Homo heidelbergensis, with the lineages though to have diverged ~700,000 years ago, but recent genetic research has revealed interbreeding of hominins in the last 100,000 years, with around 2% genomic overlap between human and Neanderthals, contributing to some anatomical characteristics in modern humans. All species evolve to adapt to their environments, however contemporary understanding of past hominins is also shaped by social contexts, leading to the shift in perspectives from 'violent savages' to a more cultured and peaceful view.
Professor Smith's dental research, explained more thoroughly in her book The Tales Teeth Tell, found that since teeth cells record details of their environment, they can also be used to track Neanderthal childhood development. By adding markers to the teeth and then counting 'time lines', similar to dendrochronology, the age at death and other major life events can be calculated. Since historical research was based on the incorrect assumption that humans and Neanderthals grew at the same rate, this allows for a more accurate Neanderthal developmental timeline, showing that Neanderthals grew much faster than modern human children. Anthropological research has advanced with new developments in dental imaging, including synchrotron microscopy and laser mapping. Professor Smith's analyses of barium levels and oxygen isotopes within teeth provides a more detailed insight into Neanderthal developmental stages as well as environmental influences such as geography and prehistoric climate patterns.
Listen to Tanya's talk: click here
Slides: click here
About the speaker
Professor Tanya Smith
Australian Research Centre for Human Evolution & Griffith Centre for Social and Cultural Research,
Professor Tanya Smith works at the Australian Research Centre for Human Evolution (ARCHE) and the Griffith Centre for Social and Cultural Research (GCSCR) at Griffith University. She has also held a professorship at Harvard University, and fellowships at the Radcliffe Institute for Advanced Study and the Max Planck Institute for Evolutionary Anthropology. Her area of expertise is the study of tooth growth and structure and she is the author of the book 'The Tales Teeth Tell'. Her research encompasses aspects of developmental biology, oral biology, and evolutionary biology, and employs fundamental histological approaches as well as state-of-the-art imaging techniques all motivated by a desire to fully understand how teeth grow, why they vary, and how this information can advance the field of human evolutionary biology.