Archaeoanthropology: How else build a picture of the past ? Géraldine Sachau-Carcel 1 2* , Dominique Castex 2 , Robert Vergnieux 3 1- UMR 5607 AUSONIUS, Bordeaux 3, France 2- UMR 5199 PACEA-A3P, Bordeaux 1, France 3- UPS SHS 3D n°3551, France *- correspondence: geraldine.sachau@etu.u-bordeaux3.fr 2012 2012 2012 2012 2012 2012 Congrats: Pontiicale Commissione di Archeologia Sacra (Rome, Italie), Maison des Sciences de l’Homme d’Aquitaine (Bordeaux, France) References: Blanchard (Ph.), Castex (D.), Coquerelle (M.), Giuliani (R.), Ricciardi (M.), A mass grave from the catacomb of Saints Peter and Marcellinus in Rome, second-third century AD, In: Antiquity, 81, 2007, 989-998. Castex (D.), Blanchard (Ph.), Giuliani (R.), Ricciardi (R.), Les ensembles funéraires du secteur central de la catacombe des Saints Pierre-et-Marcellin (Rome, Ier-IIIe siècle) : caractérisation, hypothèses d’interprétation et perspectives de recherches, Mélanges de l’Ecole Française de Rome. Antiquité, 2007, 119-1, 274-282. Castex (D.), Blanchard (Ph.), Les sépultures du secteur central de la catacombe des Saints Pierre-et-Marcellin(Rome). État des analyses bio-archéologiques et perspectives, Mélanges de l’Ecole Française de Rome. Antiquité, Rome, 2009, 121-1, 287-297. Castex (D.), Blanchard (Ph.), Le secteur central de la catacombe des Saints Pierre-et-Marcellin (Rome, Ier-IIIe siècle). Indices archéologiques d’une crise brutale de mortalité. Mélanges de l’Ecole Française de Rome. Antiquité, 2011, 123-1, 274-280. Cleuvenot (E.) et Houët, (F.), Proposition de nouvelles équations d’estimation de stature applicables pour un sexe indéterminé, et basées sur les échantillons de Trotter et Gleser, Bulletins et Mémoires de la Société d’anthropologie de Paris, 1993, 245-255. Duday, (H.), Archaeological Proof of an Abrupt Mortality Crisis: Simultaneous Deposit of Cadavers, Simultaneous Deaths?, In D. Raoult, & M. Drancourt (Eds.), Paleomicrobiology and Past Infections, Springer Berlin Heidelberg, 2007, 49- 54. Sachau (G.), Castex (D.), Mora (P.), Vergnieux (R.), Modélisation de deux ensembles funéraires de la catacombe des Saints Pierre-et-Marcellin à Rome : objectifs et méthodes, In : Vergnieux (R.), Delevoie (C.), Actes du colloque Virtual Retrospect 2009, Archéovision 4, Éditions Ausonius, Bordeaux 2010, 161-170. The development of informatics tools has eased their use in archaeology and in biological anthropology, especially the three-dimensional representation. That’s why this technique is selected to give back two mass graves of Saint Peter and Marcellinus catacomb. To study a grave and especially multiple burials, it is indispensable to search to restore the original picture of the grave (Duday 2007: 49-54). The discovery in 2002, of several multiple burials in a particular sector of Saints Peter and Marcellinus catacomb has initiated this project. The central sector of this Roman catacomb is dated to the 1st-3rd c. A.D. and approximately 3 000 individuals are burried. The funeral practices are particular and most of individuals are coated of amber, textile and plaster, giving the appearance of mummies (Blanchard et al. 2007: 990). Sometimes, many gold wires have been discovered. The large number of skeletal remains suggests an epidemic of great importance or a succession of mortality crises spread over time (Castex et al. 2007, 2009, 2011). Two graves, completely excavated are modelling with three-dimensional process to understand logic deposits and determinate if many bodies are deposited together, in the same time or not. The graves contained 74 and 76 individuals (T16 and T18). At the moment of the discovery, the height of the skeletal remains was 60 and 80 centimetres, it’s a most unusual phenomenon. The position on deposit is different for each grave, the decubitus is the predominant position but many cases of procubitus and lateral positions are observed. Methods To propose a 3D representation is important to know what is modelled and what element must be restored in terms of archaeoanthropology problematic. For this tomb all of element was important because it’s a unique example of mass grave that excavated in roman catacomb. The aim has to pass from 2D representation –records, photography...- to 3D. So, the modelling is based on ield documentation especially records on which are drawn each bone observed of each individual. It was necessary to have the exact position of each bone, each element of funerary and funerary space in three-dimensional coordinates X, Y and Z (Sachau et al. 2010). The funerary space is restored with photogrammetric records. The modelling for individuals is realised in three steps, in irst: acquisition on 3D spatial coordinates, in second: modelling of each element (bone, funerary, space funerary) and in third: all of elements modelled are assembled in a one ile, a 3D scene. To reconstitute the deposit of bodies, they are modelled in wireframe, 3D skeleton and volume bodies. Each step permits to visualise in 3D the interaction between each individuals, between funerary and funerary space. Bones are represented in opaque if the bone is recorded and in transparent if the place of the bone is supposed. An open 3D model of skeleton is used to represent human skeleton remains. Indeed, the skeletal remains stemming from the sector central had a too poor conservation to scan and used them. No other 3D human skeleton based on a reference collection exists. All of bones are not conserved, to obtain stature of each individuals for the bodies volume restitution, we have used where possible the in-situ measurement of femur or the estimated measurment with coordinates of femur. For the individuals whose femurs were not kept we used comparisons and estimates from other bones (Cleuvenot, Houët 1993: 245-255). Summary and conclusions The use of 3D models allows to have more pertinent results than a 2D representation with tests of hypothesis and a new visualisation. Beside, the use of 3D models provides data backup, reproductibility of analysis and a reading structured data. The 3D model is evolving and can be enriched by new hypothesis and new discoveries. The others tombs of the central sector are still being excavated and comparison of operation of each tomb may be particulary interesting for understanding the global operation of this sector, during mortality crises in Rome, during the irst centuries AD. This type of representation is particularly adapted for study a lot of human remains and a complex stratigraphy. Nevertheless, the elaboration of a human skeleton, based on a reference collection may improve the precision of restitution and analysis. This project permits to develop a protocol and a method adapted to restitution of mulitple burials, identifying essential data modelling to apply at other sites. Results The analysis of 3D scene permits to conirm hypothesis, to demonstrate the simultaneous deposit and to bring new relexions of this graves. The building of 3D scene permits to create not only a 3D picture but an ininite of 3D picture and to visualise multiple burial under all angles. The 3D permitting to visualise precisely all of individuals, it is possible to study the imbrications between one or several subject. In the picture 6, you can see an imbrication in 2 subjects, a immature in light green who passes between the legs of a adult subject in green, this is arguments in favour of a simultaneity deposit. Other examples have been seen, discussed and approved by responsables of the excavation with 3D representation. Another type of information is available with 3D modelling which is impossible with 2D, this is the estimation of body volume and the placed occupied by the body, human skeletons in the grave. Indeed, the 3D modelling of skeletons and body volume permits to test the free place available after each deposit and when the grave is full and placed chronological patterns of the grave usage. In this illustration, we can see the grave with all of deposit which exceed the ceiling of the tomb. So, it is not possible to deposit all of bodies in the same time. The pictures 7 and 8 show that only 22 subjects on 78 have been deposited simultaneity. The understanding of usage of grave is based in part on arguments of simultaneity. These permit to understand the operation of the grave during mortality crises. The analyse of 3D scene of these two graves show that usage is most complicated as we can think with periods of simultaneity deposit and periods of waiting between deposits making it multiple/collective grave. The 3D representation permits too, to study circulation spaces, repartition by sex, age and apprehend the logical deposits therefore bodies management. We have so able to show that the body were prepared place outside the tomb, and there was likely a selection according to stature. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 1: photography of a level of deposit (6), tomb 18, sector central of catacomb of Saint Peter and Marcellinus. Figure 2: Field record of one level of deposit (level 6) of one tomb (T18) of sector central of Saint Peter and Marcellinus Figure 3: 3D reconstitution in wireframe skeleton of level 6 Figure 4: 3D reconstitution in 3D skeletal of level 6 Figure 5: 3D reconstitution in body volume of level 6 Figure 6: 3D representation of an imbrication between a immature subject and an adult subject. Figure 7: All of skeletal deposit in tomb 18 of sector central, 3D skeletal. Figure 8: All of body volume deposit in tomb 18 of sector central, 3D body volume.