Podium - Wed 4th (18h00) Application of micro tomography to the mandibular incisors of Sima de los Huesos Annabelle Lockey *† 1, María Martinón-Torres 1,2, Laura Martín- Francés 3,4, Juan Luis Arsuaga 5,6, José María Bermúdez de Castro 1,7 1 Department of Anthropology, University College London (UCL), London, United Kingdom 2 Laboratorio de Evolución Humana (LEH), Departamento de Ciencias Historia y Geografia, Universidad de Burgos, Burgos, Spain 3 de la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (PACEA), UMR5199, CNRS, Université de Bordeaux, Pessac, France 4 Fundación Atapuerca, Burgos, Spain 5 Centro UCM-ISCIII de Investigación sobre la Evolución y Comportamiento Humanos, Spain 6 Departamento de Paleontología, Facultad de Ciencias Geologicas, Universidad Complutense de Madrid, Spain 7 Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Burgos, Spain Dental tissue proportions are regularly reported as a diagnostic feature within hominin characterization, and are linked to dietary reconstructions and non-masticatory function. Until recently dental tissue proportions were inferred from linear measurements extracted from physifically slicing teeth, or observing natural random fractures in teeth; these irregular and destructive methods have been critiqued heavily. Microtomography has led to advancements in this field, with standardised non- destructive methods applied to valuable fossils, allowing for larger samples to be analysed with high resolution. Hominoid incisors are severely under investigated in the archaeological record for all aspects of dental tissue measurements, despite implications to non-dietary behaviour. Studies into Neanderthal anterior dentition have reported that they are larger than expected, and adapted to heavy wear and frequent loading. Important excavations at SH represent a Middle Pleistocene population belonging to a much wider group of sites found at Sierra de Atapuerca (Burgos, Spain), widely renowned for significant contributions to the study of human evolution. A large accumulation of hominin remains have been systematically excavated from SH, with 62 of the 525 permanent teeth identified as mandibular incisors. Analysis of SH material has had significant implications concerning the origin of Homo neanderthalensis, and provides an excellent opportunity to study a hominin population constrained geologically and temporally. Here we report the results, using MicroCT and geometric morphometric analysis, of Sima de los Huesos (SH) mandibular central (6) and lateral incisors (8). A comparative sample of modern humans (35) and Neanderthals (7) will also be examined, this will aid in phylogenetic analysis of the SH material expanding valuable data sets, and hopefully encourage further research into anterior dentition. Results indicate that the SH population holds an intermediate position between Neanderthals and modern humans, with a notable increase in dentine surface area relative to modern humans. Keywords: Atapuerca, dental tissue, microtomography, incisor * Speaker † Corresponding author: [email protected] 31 .