Identification of human vs non-human bone (Sus Scrofa) in forensic anthropology : Histological perspectives

In the event of natural disasters, residential and commercial fires, aircraft accidents as well as in clandestine burials, fragmented remains of pets, wildlife animals or other animals used for meat consumption (e.g. pig, cattle), can frequently become commingled with human remains. In such cases, forensic anthropologists are often asked to assist law enforcement in identifying the human or nonhuman origin of the remains. When the skeletal material is highly fragmented lacking any diagnostic feature, species discrimination by the assessment of gross morpohological characteristics may not be exploitable. Thus, forensic anthropologists must turn to other methods, such as the histological analysis. Though bone histology of mammals has been deeply explored since at least the seventeenth century, quantitative data available to perform species discrimination by histological analysis is still scarce and, above all, there is a lack of knowledge on the extent of variability in different bones of the skeleton, considering that most of the previous investigations focused exclusively on some specific bones (e.g. femur, rib), rather than having a wider overview of the entire skeleton. In this regard, this thesis aimed to investigate the intra- and inter-species variability of bone microscopic structure in human and pig (Sus scrofa) at different stages of skeletal maturity from both a qualitative (type of tissues) and quantitative perspectives (measurements of diameter, area and perimeter of secondary osteons and osteocyte lacunae). More than 3000 osteons and Haversian canals were measured during the analyses, as well as over 1200 osteocyte lacunae. This research demonstrated a significant intra-individual, intra-species and inter-species variability of bone microarchitecture which can have implications not only when II assessing the origin of an unknown bone fragment, but also when performing histological age-at-death estimation. Overall, it makes a significant contribution to knowledge of bone histomorphology and histomorphometry in human and pig since it represents the first attempt in investigating bone microarchitecture along the entire human and pig skeleton and provides new insight for species discrimination from a histological perspective’