What is forensic entomology? It is a discipline within forensic sciences where specialists use information that they know about insect lifecycles and behaviours to interpret evidence in a legal context, relating to humans and animals. Entomologists don’t just stick to insects; their work can expand to include other arthropods, mites, spiders and macro-invertebrates.
What information can we learn from insect activity? Insects are everywhere and can hardly be avoided, so it’s no surprise that sometimes they get mixed up in the evidence left behind – making them extremely valuable to an investigation. Insects can be a vital part of forensic science as they can provide a time and date to a crime or even a geographical position to where it happened. As some insects only become apparent during certain months, they can become a biological calendar for when a crime might have been committed. As well as being a biological calendar, certain insect species are only native in specific countries or hemispheres. This can be used to create an ‘X marks the spot’ on where a crime was committed – even if a body was moved/buried. Because of this, insects can be the key to past and present events as well as the future.
The insects that are particularly relevant to forensic entomological investigations are blow flies (diptera), flesh flies, cheese skippers, hide and skin beetles, rove beetles and clown beetles. These forensically relevant insects can be placed in four categories:
- Necrophages, which feed only on the decomposing tissue of the body or body parts. This is the category that blow flies, hide beetles and clown beetles are classed under.
- Predators of the necrophages – for example the rove beetles and ground beetles.
- Omnivores that consume both the live insects inhabiting the corpse and the dead flesh – ants and wasps.
- Opportunist species, which arrive because the corpse is a part of their local environment. This is where mites, hoverflies, butterflies and occasionally spiders are classified.
Forensic entomologists use the evidence they gain from studying insects within legal cases in either civil or criminal courts. Civil court cases include:
- Insect infestation in urban contexts.
- Stored product infestations/pests.
Criminal court cases include:
- Neglect – either animal or human (elderly and children).
- Insect infestation of a body – living or dead.
- Death in which foul play is suspected.
This is just an introduction into the world of forensic entomology, if you’d like to know more or further your knowledge on this topic check out this book, I found it very interesting and a terrific read:
- Forensic Entomology: An Introduction (UK/Europe)
Forensic Entomology: An Introduction (US/Worldwide Link)
by Dorothy Gennard. Rating – ***
“I used my this for my blog post on the basics of forensic entomology. It is perfect if you’re unsure on whether or not you want to pursue this career/discipline. Definitely a good read if your interest is sparked by Dr Hodgins from ‘Bones’, as it explained everything involved within entomology under legal settings.”
Fantastic post! Although I would say that many mite genera are not just opportunist and are solely associated with corpses. Certain mites are already present in the soil but there are many that arrive with other necrophagous animals. I have shared this if you don’t mind 🙂
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