Seminar of Physics of the Living State

(The Applied Physics Scientific Section)


2011 Academic Year

Thursday, 28 July 2011

Time: 15.00

Euler Lecture Hall, Terrace Level, Leonardo Building



Virtual dental paleoanthropology:
From outer to inner structural morphology (*)

Clément Zanolli (**)

Département de Préhistoire,
Muséum national d'Histoire naturelle, Paris, France



(*) Summary. Due to their own structural nature, teeth represent the most abundant elements in the fossil record and form the best evidence illustrating human chrono-geographic variation and biocultural evolution. Recent methodological advances in the fields of developmental biology, quantitative genetics, structural and comparative microanatomy show that a rich and varied amount of information is preserved at different levels in the dental tissues. However, a critical portion of this record, which is crucial for assessing the evolutionary pathways and phylogenetic relationships, adaptive strategies and fluctuating variation patterns, dispersal routes and paleoecological contexts, seasonally-related health conditions, sex- and age-related timing and patterning of development and growth in extinct taxa (including even fragments of individual life-histories), lies imprinted deeply inside the crown and the root(s).
In addition/alternative to histomorphometry, which can be used only parsimoniously in paleoanthropology, the increasing use of noninvasive analytical techniques (such as those based on microfocal X-ray computed tomography) capable to virtually explore, to extract, to "clean", and to finely render at varied resolutions the even noisy signature hidden in fossil specimens, has recently opened new promising research perspectives in the field. Notably, this implies the 3D (vs. 2D) imaging of mineralized tissues and the surface/volumetric (vs. linear) characterization of their structural variation.
Nonetheless, a reliable investigative shift from outer to inner dental morphology does not only require advanced techniques (and technologies), but also new fundamental concepts concerning what and how should be rendered and characterized, both qualitatively and quantitatively, in routine analytical protocols. In this perspective, together with the need to extensively report extant/recent inner morphostructural variation, a long-term multidisciplinary work of significant methodological value is still needed. By using a large original "virtual" dental sample representing fossil apes (e.g., Oreopithecus, Ouranopithecus), hominins (e.g., Australopithecus), and humans (H. erectus, H. heidelbergensis, Neanderthals, anatomically modern extinct humans), I will discuss the implications of fresh results concerning the taxonomic-related variation of deciduous and permanent dental tissue proportions (including enamel thickness variation and dentine volume), enamel-dentine junction shape, and virtually unrolled tooth root topography rendered by means of morphometric maps.

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(**) Biodata: Clément Zanolli is completing a Ph. D. at the National Museum of Natural History in Paris, France. He is the author of numerous publications in significant specialized journals and has often participated in conferences.

He obtained his first degree in 2005 in Biology, Geology, Earth and Life Sciences at the University of Rouen. He continued to a Master Degree, obtained in 2008, in paleoanthropology at the same university.

His area of expertise is in paleobiology and paleoanthropology with extensive experience in relevant experimental techniques. He has however to his credit also shown interest in science communication. He will talk on a fascinating topic that is very close to our own interest in this Centre, the M-Lab directed by Claudio Tuniz. The title of the talk is: Virtual dental paleoanthropology: from outer to inner structural morphology.