Entomological and taphonomic aspects of non-suspicious deaths and their implications for forensic interpretation
I have a background in environmental archaeology and forensic research with research interests focusing on entomology, taphonomy and issues affecting preservation.
This project follows on from a successful pilot study undertaken in the Division of Pathology. The underlying premise of the research is a better understanding of post mortem interval (PMI) in the Scottish context, as expressed by insect growth and taphonomic issues associated with a dead human body. It is now universally accepted that provided adequate food is available, insect growth is directly related to temperature. Nevertheless, although a reasonable wealth of published research is available on the subject of PMI that allows extrapolation from laboratory and field studies to fatal crimes in Scotland, the analogies are far from sufficient and uncertainties concerning variation in geographic populations of insects remain.
There is reason to believe that the Scottish populations of species present in Scottish forensic instances are cold tolerant, in contrast to studies reported in the literature on the identical species from elsewhere in the world, that tend to originate from warm temperate to subtropical climates.
The methodology suggested by this study encompasses two main routes of investigation, both intimately interlinked:
- the collection, curation and evaluation of insects collected at autopsy and death scene, with subsequent establishment of PMI time lines
- the gradual accumulation of the data and an arthropod reference collection to form a database of Scottish case studies.
Death scenes are being treated as proxies for forensic contexts. Standard European Crime Scene Protocols (Amendt, J. et al. 2006), and professional archaeological recovery techniques are being applied to record and collect data with the view the research will then have the potential to aid future forensic interpretation and the conclusions drawn from it.
Additional areas of investigation during the project will include preferences of Diptera for particular gases of human decomposition, the level of decomposition of human cadavers and their internal organs in relation post-mortem interval and human decomposition rates in relation to other variables, both biotic and abiotic.
Reference: Amendt, J., Campobasso, C.P., Gaudry, E., Reiter, C., LeBlanc, H.N. and Hall, M.J.R. 2006. Best practice in forensic entomology - standards and guidelines. International Journal of Legal Medicine 121: 90-104.
|Dr Ralph BouHaidar||Forensic Pathologist||Email Ralph BouHaidar|