Forensic Entomology

Forensic Entomology
Forensic entomology is the use of insects that collect on remains to aid in a criminal investigation. The history of entomology dates back to 1235 a.d., leaving a wide spectrum for the development of it. The field is broken down into three general areas: medicolegal, urban, and stored product pests. There are many types of insects involved with forensic entomology, from blowflies to moths and beetles. Entomology is important to many investigations, and can sometimes be the only thing that can possibly save a case.
Entomology has been recorded back to 1235 a.d. with Sung Tz’u who was also known as the “death investigator”. His book, The Washing Away of Wrongs, was translated in 1981 and showed how forensics was used at that time period. An account from a murder in a small village was accounted, and entomology was used to find out who did it. They were asked to bring their sickles to him, lay them out and flies were attracted to the one that was used to commit the crime. Dr. Bergeret d’Arbois was the first person to apply forensic entomology that had an estimation of postmortem interval (PMI). The first systematic study in forensic entomology was conducted in 1881 by Reinhard, who exhumed bodies and discovered that different species of flies determined how long the body had been there. Jean Pierre Mégnin, an army veterinarian, published two books on entomology, Faune des Tombeaux and La Faune des Cadavres. His second book revealed that there was a pattern to what insects arrived on a body and at what time. His experiments assessed that there were eight patterns of insects that a single corpse would endure in a period of time. Throughout the evolution of entomology many books, articles, and magazines have been published releasing the advancements that have been discovered. According to the website, Forensic Entomologist, “The first textbook devoted to forensic entomology was published in 1986: A Manual of Forensic Entomology (Smith 1986). This is an excellent reference for the entomologist, and it brings together in one place all the salient information contained in the literature on this subject.” As different techniques are discovered, publications will continue to be printing and released to the public. The new technologies of today allow for more accurate investigations and possible criminal convictions. Entomology is among the advancing technologies as much as the computer age advancements. Forensic entomology is now finding ways to determine DNA from what is collected from the insects. This is still an advancing portion of the technology and will be useful more so in the future.
The Forensic Entomology website determines that “Forensic Entomology, or Medicocriminal Entomology, is the science of using insect evidence to uncover circumstances of interest to the law, often related to a crime.” The different types or categories of entomology include: medicolegal, urban and stored product pests. Medicolegal entomology includes murders, rapes, and other physically damaging crimes. Murder investigations, and sometimes suicides and possible accidents, this type of entomology is used to determine how long the person has been deceased by the eggs laid by the insects and what order they appear in. This is essential in determining the predicted time of death and the possible location of the body at the time of death, in case they were possibly moved. The newest movement in medicolegal entomology is entomotoxicology, which involves removing and analyzing for remnants of toxins from flies or beetles that have ingested matter from a body. This helps investigators determine what toxins were possibly present at the time of death. Urban entomology deals more with how insects affect humans and their environment. This allows investigators to determine how the different insects feed on living and dead bodies. This also is leading investigations in criminal, environmental and civil cases. Stored product pests are used for investigations into food that is shipped to different places, and how they could affect that new ecosystem. Both the urban and stored pest entomology are focused on the environmental affects insects have on the environment. These also aid in investigations by showing what chemicals may have been used at a location for pest control. There will be an abundance of a certain insect and a lack of another, depending on the chemicals in the area. From the types of entomology, now the types of insects involved with entomological investigations.
The different types of insects that arrive at the scene of a body are very important for the determination of the time of death and initial location of the body. Flies such as the blowfly and the black soldier fly are used to determine length of time the body has been there. The adult flies lay eggs that can reach maturity over a period of _____ days, but maturity is reached away from the corpse after migration from the body. “The larvae of flies that are commonly recovered from decomposing human remains lack functional legs, and the body of many species appears cream colored, soft-bodied, and quite "maggot-like". For a picture of some of the maggots commonly found on human cadavers.” If maturity is reached there is the timeline of those days plus the evidence of other insects like the Rove or Hister beetles that sustain their lives longer at a corpse than that of the flies. Beetle larvae are almost identical to the larvae of blowflies but can be determined as beetle larvae from certain characteristics including, being either white or brown in color, large or small in size, and being hairless or hairy. The range is much more vast than the fly larvae. Skin or hide beetles are the last to arrive at a corpse and feed off the dry skin, and break down keratin from the hairs left on the body. Most mites are found at the beginning stages of decomposition, while others arrive at the same time as the skin/hide beetles. Some mites feed on the fly larvae which can lead to miscalculations in the presumed time of death. Moths are the last to feed off the hair on a body, and finalize the decomposition stages. Bees, wasps, and ants have been reported to feed off bodies, but many are predatory and feed off the other insects inhabiting the body and area. Which again causes problems for the time of death and location determination.
Forensic entomology started with simple experiments and has evolved overtime, and will continue to evolve in the future. The study of insects and the environment they and we live in are essential to our way of life. Without insects the ecosystems would be off balance, and forensics would also be weakened by the lack of species needed to solve many cases. Entomology is used for criminal investigations, environmental and everyday life improvements. Imports and exports will always have something to do with entomology, for if one type of foreign insect gets in a country, it could ruin entire ecosystems. Forensic entomology will continue to be useful in many investigations and will sometimes be the only thing that will break a case and solve a homicide.