The effect of accelerants and fire on blow fly colonisation and development

: implications for forensic entomology and determination of minimum Post-Mortem Interval

Abstract

Previous studies have observed that alterations caused by fire can have a significant impact on insect colonisation and body decomposition. In fact, in the event of a fire, changes in the physical structure of the body and a change in odour can affect oviposition behaviour and subsequently decomposition processes. A full understanding of this impact is paramount for an accurate minPMI estimation, but little information is available on the effect of fire on insect activity. For this reason, a series of studies were conducted to investigate the effects of fire and ignitable liquids on the larval development of the primary coloniser Calliphora vomitoria when feeding on substrates contaminated with ignitable fluids and burnt at different levels of burning. Complementary to these studies, a series of outdoor experiments were performed in order to assess the impact of fire and ignitable liquids on the decomposition of animal carcasses, and to investigate potential differences on insect colonisation and larval development. Sometimes fire can be started days after the death of an individual, when insect colonisation already occurred. For this reason, two experiments were conducted in order to investigate the possibility of recovering insect evidence at the scene after a fire is extinguished. The purpose of this research is to have a broader understanding of the influence that burning and the use of ignitable liquids can have on body decomposition, insect colonisation, larval development and the retrievability of insect evidence after a fire. All these factors should be taken into account when investigating a fire scene involving a deceased body, especially when a forensic entomologist is called to provide an estimation of the minPMI, since ignoring these factors could lead to an inaccurate minPMI estimation.

Date of Award	16 Nov 2023
Original language	English
Awarding Institution	University of Winchester
Supervisor	Amoret Whitaker (Supervisor), Keith Wilkinson (Supervisor) & Dave Clemens (Supervisor)