Experimental Bone Taphonomy: A novel approach to long-term and monitored analysis of postmortem changes to bone

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Although the decomposition of soft tissue has been well studied, very little experimental research has been conducted on natural decomposition of bone tissue because such studies take a very long time and require dedicated facilities. This research program wishes to fill this gap and start investigating on a long term scale the unique changes associated with the chemical and physical breakdown of bone tissue which occur during the decomposition and exposure of bone after death in ground-surface/sub-aerial terrestrial environments. This research will establish a fenced open air taphonomy facility equipped with meteorological and environmental statons that is unique in Canada. In this facility, specimens will be left to decompose for consecutive time periods and environmental variables, such as scavenging or temperature, are either controlled for or strictly monitored. The analysis of chemical and physical destruction of bone will be carried out using an innovative research design, along with a more traditional approach. In the traditional design, all samples will be laid out in the field at the start of the experiment and then a portion of the samples will be removed periodically, until they have all been recovered. In my new research design, only the oldest samples will be laid out in the field at the start and then additional specimens are added periodically, until all samples are in the field at the end of the experiment. One of the major advantages of the novel design is that the end of the experiment does not need to be determined at the start and, in theory, can go on indefinitely. In comparison, traditional approaches that rely on collecting the specimens at regular intervals must start with a clear indication of how long will the experiment last. This novel design has only been developed and tested recently and my preliminary research has demonstrated that it is as good as or better than the traditional design for assessing the sequence of changes and their variation relative to season and annual variations in environmental factors, such as temperature. Major expected result is the identification of general thermodynamic and kinetic parameters of surface and subsurface bone tissue degradation with important implication for understanding general ecological and environmental dynamics. In the shorter term this study will also allow the identification of morphological and chemical-physical changes in bone tissues related to time of death and environmental conditions. Thus the broader impact of the proposed study of bone decomposition is key to the understanding of the post-mortem environment of animal and human remains found in geological, archaeological or forensic contexts. Changes in animal or human bones from a geological (a fossil) or archaeological context can provide vital clues about the ecology in which the individual most likely lived, and about the chemical and physical changes that mediated its transformation into a fossil or pre-fossil. Those same changes found in human remains from a forensic death scene also provide vital clues about time since death. In addition, distinguishing natural from man-made bone modifications is key to the interpretation of butchering activities in archaeological contexts, but also to the determination of cause of death from forensic human remains where a suspected violent death is involved. This research will considerably expand the current knowledge base relating to decomposition of bone in ground-surface/sub-aerial terrestrial environments and the processes that influence the rate of bone change over time. It will also develop HQP with highly desired skills who will promote the research excellence of Canada in fields such as paleontology, taphonomy, zooarchaeology and archaeology or