Forensic Entomology

Forensic entomology is described as ‘the branch of forensic science in which information about insects is used to draw conclusions when investigating legal cases relating to both humans and wildlife although on occasion the term may be expanded to include other arthropods.’

There are many different aspects of forensic entomology including estimating time since death, identifying whether or not a body has been moved from a previous location, establishing whether drugs and toxins were an aspect of the crime and wound identification. Due to there being such a wide variety of topics within forensic entomology this essay will be focusing on estimating time since death of a body that has been left in the open. Bodies that have been buried or tightly

This can be attributed to the predictable life cycle of the insects as well as their eating preferences as decomposition takes place. It is very common for the first insect to arrive at the body to be a blowfly, some even appearing just 10 minutes after death. The lifecycle of the blowfly is very predictable, and minimum time since death can be estimated by looking at the different stages that the larvae is at. The first stage initially begins with the female blowflies that have arrived at the body laying their eggs in the body’s natural orifices as well as any open wounds on the body. These eggs can also be identified as blowfly eggs before they hatch due to their characteristics of being white and very shiny, with an estimated length of between 0.9mm and 1.50mm and an estimated width of between 0.3mm and

Another more reliable way of determining age would be by looking at the slits that have formed in each of the posterior spiracle. The first instar larvae will have one slit, the second will have two and the third will have three.

Approximately half way through the third instar the larvae must being preparation for the pupariation stage where the larvae will make the transition from larvae to blowfly. To do this they stop feeding on the body and begin to move away in search of a dark, cool area and are often found to have buried themselves within soil (if present) reaching approximately 2cm-3cm down. This is commonly known as the post feeding and wandering stage of the third instar. Depending on the environment of the crime scene some of these larvae have been found up to 30 meters away from the body in an attempt to find a suitable