Mrs. McConnell
Forensics
22 September 2014
Bugs Determine Time of Death
Forensic entomologists use the presence of insects to help determine approximate time of death of corpses. How can insects tell us time of death? Forensic entomologists use two main methods to evaluate approximate time of death in, one method looks at what type of insects are on and in the decomposing body and the other uses the life stages and life cycles of certain insects to establish how long a body has been dead. One of the first insects to settle into a freshly dead body is the blowfly. Blowflies have a number of different life cycles starting with an egg stage, moving onto three different larval stages, and going through a pupa stage before emerging as an adult. Because of the extensive study of blowfly life stages and a working knowledge of the length of the each life cycle a time of death, to within a day or so, can be determined from the stage of blowfly colonization on a body. Many other insects come to the body after the blowfly. Here are some of the things that insects help forensic entomologists discover about a body: Drugs- By analyzing the bodies, shed skins or faces of flesh-eating insects found at a crime scene, forensic entomologists may be able to determine whether drugs were used, and which they were. DNA- Forensic scientists can extract the DNA from blood consumed by blood-sucking insects. This can be used to place someone at the scene of a crime, supported by evidence of bite marks. Although insects greatly help forensic scientist in crime scenes, they can cause difficulty as well. Insects can walk through bloodstains and leave bloodstained droppings at crime scenes, which can cause confusion. Overall, forensic entomologists use insects to determine PMI, the location of death, legal cases involving mysterious, sudden death where foul play is suspected, traffic accidents with no apparent cause, and criminal misuse of insects.