New data on the paleobiology of the Gravettian individual L2A from Cussac cave (Dordogne, France) through a virtual approach

Abstract

One of several elements making Cussac cave an exceptional site is the preservation of many prehistoric human remains lying on the ground, including an individual in a bear nest (Locus 2) in ventral decubitus, subject L2A. The protected status of the site does not allow for excavations or direct manipulation of the remains, at least for the near future. Thus, the tools of virtual anthropology were employed to further study this individual, after preliminary analyses in situ in 2014 raised several questions on its biological characteristics. A high-resolution 3D photogrammetric record of Locus 2 allowed for the virtual reconstruction of the ossa coxarum and cranium to be measured in TIVMI. Metric data from the ossa coxarum were used to apply the DSP, which indicated a male sex assessment for the left side. The linear variables and log shape ratios extracted from the cranium were compared to a reference sample composed of 46 Upper Paleolithic (UP) subjects. The cranial morphology of L2A is closer to the male variability for the UP, but displays an unusual pattern, with a short cranial height and a wide splanchnocranium. The biological peculiarities of this subject are discussed with regard to Gravettian funerary practices and the depositional context of Cussac cave.

Ultra close-range digital photogrammetry in skeletal anthropology: A systematic review

“…The applicative studies mainly dealt with the documentation of skeletal findings [55,66,67], including their taphonomy [44,62]; the identification or comparison of anatomical features and trauma [8,58,63,68]; the use of three-dimensional printing techniques for communication and educational purposes [69]. Their focus was related to fossil remains within the human lineage until the early development of anatomically modern humans, hence falling into the field of Palaeoanthropology [12,57,63,69], prehistoric and historic samples [55,[59][60][61][62]66,67,70], or with contemporary skeletal remains [5,6,68,8,11,14,37,56,58,64,65].…”

“…Shooting. Sixteen studies [6,8,58,63,64,67,68,70,11,12,14,37,44,[55][56][57]-over 23 producing 3D models-specified the shooting protocol, while other studies provided fragmentary information ( Table 2).…”

“…Most authors used a commercial solution-mainly PhotoScan (Agisoft, Russia) [6,8,[60][61][62]67,70,11,12,14,37,44,55,57,59] or PhotoModeler (EOS Systems, Canada) [64,68]-while [75]) and MeshLab [56], or did not give any information [65]. Within the studies adopting discrete shooting sessions (Table 2), the alignment and merging of the partial meshes for 3D reconstruction was realised using MeshLab [56,70], PhotoScan [55,57], or CloudCompare [63]. Different algorithms were applied, such as the least-squares optimization [63] and the iterative closest point (ICP) [8,12,70] for the alignment, and the Poisson remeshing algorithm [70] for the fusion.…”

“…Scaling details were reported by a minority of the reviewed studies. The procedure was based on reference scales included in the frame [55,58,63,68,70], or on linear measurements [11,12,56,57] taken on the actual specimen and then applied to the 3D model. The measures were taken a single time [56,57], or were repeated [11,12]; in all cases along one axis only.…”

“…Open-source software packages such as MeshLab [8,56,58,59,61,66,70] and CloudCompare [12,56,58,69] were the most used in many contexts. Some studies used commercial software for specific tasks: Photo-Scan [67]; Geomagic Studio [11], and Geomagic Wrap (3D Systems Inc., United States) [55,70].…”