In criminal forensics flies of the species Calliphora vicina have an important role in post mortem interval determination. Factors such as region, weather, temperature, time of day and conditions under which a body was found all contribute to determining a post mortem interval which is the time that has elapsed since a person has died. For a precise calculation a forensic entomologist must consider what is commonly known about the species and integrate it with experimental data gathered from a crime scene. It is essential to know how the blow-fly behaves specifically in the area where the body was discovered. Calliphora vicina and a few other fly species are currently widely used in criminal forensics because of their consistent time of arrival and colonization of a corpse.
This knowledge played a big role when researchers of the Zoological State Collection in Munich, Germany used DNA Barcoding to determine the species identity of some maggots that were found in soft cheese. The sample came from a large German cheese manufacturer as they suspected improper storage that led to the infestation. The species identity would allow to extrapolate the time of oviposition. This in turn would allow the manufacturer to confirm their suspicions by crosschecking with information of their chain of custody .
|Stinking Bishop (just an example for a |
smelly cheese. Not the one sampled!)
Indeed the researcher were able to help. The maggots clearly belonged to Calliphora vicina which not only likes putrescent meat but also smelly cheese. I better contain myself from speculating what the smell of rotten meat and strong-smelling soft cheese have in common but this clearly is one of those creative applications of DNA Barcoding in combination with forensic science I would never have thought of before.