Tesis doctoral
The purviews of Forensic Anthropology are the interpretation of the decomposition process of human remains, the elaboration of biological profiles, the interpretation of taphonomic effects in form of differential decomposition, disarticulation and/or lost of bone elements, and the estimation of the postmortem interval. The latter is one of the most complex tasks. In the case of remains in advanced decay, it is even more puzzling because a large range of variables affects the final cadaveric state. In Europe there is a lack of research on human decomposition, and animal models tend to be used. Using human remains from cemetery context is a way to overcome the issues related to the low availability of human corpses, the low number of remains and the antiquity of samples. The main aim of this thesis is to evaluate the influence of different taphonomical agents on the final cadaveric state observed during exhumations in cemetery context. Unclaimed human remains from Cemeteries of Terrassa, Montjuïc and Collserola were analysed, with a mean postmortem interval of 22.63 years. The sample contains 301 exhumed corpses of both sexes, predominantly adults. Description of observed cadaveric states was performed separately for each cemetery as well as for all three cemeteries together. Taphonomic, anthropological and depositional information was gathered in the exhumation record. Meteorological data were observed from three different automatized weather stations close to the cemeteries. Postmortem interval was calculated from the day of death until the date of exhumation. Five cadaveric states were established: total skeletonization, skeletonization with wet putrid matter, skeletonization with dry putrid matter and partial desiccation, mummification, saponification with wet putrid matter. The dry cadaveric state was in general predominant. The anterior parts of the corpses were more complete that the posterior parts. Intrinsic factors (sex, age, cause of death) did not show any effect on the cadaveric state, but extrinsic factors did. Plastic body bags, funerary sheets, and an increase of the height of the niches facilitated the conservation in form of wet cadaveric state. Clothes and diapers delayed the destruction of soft tissue. Autopsied corpses did not present a clear prevalence of any cadaveric state. Regarding postmortem interval, totally skeletonized corpses presented the longest time since date of inhumation. No influence of the season when the individual died or of the presence of insect activity was confirmed. The locality of each cemetery displayed unique environmental conditions that affect the observed cadaveric state. Differences among cemeteries were found, which highlights the importance of climatic differences even in similar contexts. However, the influence of meteorological variables was statistically demonstrated, for instance, on the saponified corpses with wet putrid matter. Artifacts linked to cemetery context were described and classified into two groups: those highly indicatives, and those suggestive of the cemetery origin of the remains. A new method of evaluation of joint disassociation pattern was elaborated. Joint structure was described as articulated, disarticulated or displaced based on minimum unidirectional movements to reconstruct environmental characteristics of decomposition, including human intervention. It is a useful tool to describe the funerary ritual in the case of ancient remains and the circumstances surrounding the death in forensic context. The use of human remains from cemetery context stands out as an important model to analyse human decomposition and understand the evolution of corpses in advanced state of decomposition. Prevalence of just one factor cannot be identified in cemetery conditions due to the interactions among all the factors.