EPSAM

I graduated from Keele University in 2008 with a BSc in Chemistry and Forensic Science. I then continued my studies and joined the chemical ecology group at Keele and I am now in the final stages of my PhD, having submitted my thesis and awaiting the viva.

Winston Churchill Trust Travelling Fellowship award - News and Events

Source and maintenance of recognition cues in ant societies

Lead supervisor:  Dr Falko Drijfhout

My main research focus began with applying a chemotaxonomic identification technique to three forensically important insects; Lucilia sericata, Calliphora vicina and Calliphora vomitoria. Calliphoridae hold a lot of forensic value as they are the known to be the first colonizers of decomposing remains, arriving just minutes after death. Therefore, if the insects can be aged upon discovery of a body, a minimum Post Mortem Interval (PMI_min) can be established. Identification to species level is the first crucial step in criminal investigations when trying to determine the PMI_min, since different species have different life stage timings. However, due to larvae being morphologically very similar, correct identification is only confirmed when rearing the larvae to adult flies, which is a time consuming process.

Recent studies suggested cuticular hydrocarbons present on all insects are species-specific, so this technique was applied to the three blowfly species mentioned to see if they could be distinguished in all of the six life stages. This was achieved by taking liquid extractions (hexane) of the insects and analysing them using Gas Chromatography – Mass Spectrometry (GC-MS). Statistical analysis is then applied to the collected data in the form of Principal Component Analysis (PCA). Once it was established that species identification could be determined from all six life stages, the next step was to see if hydrocarbons could be used to age the insects. Extractions and analysis was carried out in the same way as for identification. Larvae were analysed daily until pupation and the empty puparial cases and adult flies were also examined. Results showed time specific changes within the profiles, enabling an age to be determined.

Further preliminary analysis was carried out using Direct Analysis in Real-Time-Mass Spectrometry instead of GC-MS and Artificial Neural Networks (ANN) as an addition to PCA. These results, along with other, are in the process of being published.

• Hannah E. Moore, Craig D. Adam, Falko P. Drijfhout, Potential Use of Hydrocarbons for Aging Lucilia sericata Blowfly Larvae to Establish the Postmortem Interval, Journal of Forensic Sciences (2012) DOI: 10.1111/1556-4029.12016