Introduction In so far as academic studies are concerned, the field of forensic entomology is relatively new in the West—but so, too, for that matter is the field of criminology. Forensic entomology is a subset of criminology in that it focuses on the study of insects and anthropods and what they reveal about the death of a victim. This highly specialized science takes the field of entomology and combines it with the field of forensics, bringing together two very different but very useful bodies of knowledge that, when they intersect, provide valuable insights that can help investigators solve murders. This paper will define and discuss forensic entomology, examine its history and how it has developed over the years, and describe how entomology has affected the field of forensics with a few examples to illustrate this point.

History

The history of forensic entomology begins, as far as historical records show, in China in the 13th century. This is where Sung Tzu, who wrote many other works, composed two in particular that touched on forensic entomology. The first was Collected Cases of Injustice Rectified and the second was Washing Away of Wrongs. The latter dealt with identifying the causes of death and how to examine the corpse for information. The former told the story of the peasant who slew his neighbor with a sickle and was identified by the murder weapon, which attracted flies—drawn by the traces of blood left on the blade, unseen by the human eye (Rivers & Dahlem, 2014). The insects helped the authorities determine the murder weapon and the identity of the man whose weapon it was. This is the earliest known example of forensic entomology.

Other examples followed. There was Redi in 17th century Italy who proved that maggots are not spontaneously generated in the rotting meat but actually grow from flies (Rivers & Dahlem, 2014). Redi’s proof prompted more investigation into the role of insects in the decomposition of flesh. This was followed by Bergeret in France in the 19th century who applied the science of forensic entomology to an actual case for the first time in modern history. Bergeret used the evidence of larvae and pupae to conjecture about the “mummified remains of a newborn baby” (Rivers & Dahlem, 2014, p. 18) and thus made history in the West with what is now known as the first instance of forensic entomology as it is used today.

In the 20th century, the field of entomology itself began to develop even more, and as the world proceeded to go to war there was ample opportunity to apply developments in the field of entomology to the burgeoning field of forensics. Pest control was a major focus during both World War I and World War II, and by 1922 Karl Meixner had observed that the decomposition of bodies infested with maggots proceeded more quickly when the cadaver was that of a child as opposed to that of an elderly person (Rivers & Dahlem, 2014). Hermann Merkel provided insights into how wounds to a body could alter the rate of decomposition by facilitating access to insects. Josef Holzer investigated the effect of aquatic insects on submerged bodies and how certain species impacted the skin in different ways and when caddisflies lay larvae, which allowed him to guess that a particular body had been underwater for seven days, based on the fact that he found caddisfly larvae on the cadaver.

These were just a few of the examples of what investigators were doing, merging entomology with forensics. By the latter half of the 20th century, their work would begin to be studied with real earnest by professionals in the field of criminal justice, as forensics...

These were urban forensic entomology, stored-product forensic entomology, and medicolegal forensic entomology—or better known today as the most commonly known form of forensic entomology, the form that “deals with anthropod involvement in events surrounding felonies, usually violent crimes such as murder, suicide, and rape” as well as “other violations such as physical abuse and contraband trafficking” (Catts & Goff, 1992, p. 253). Urban forensic entomology focused less sensational issues—such as the lawsuits surrounding pests and anthropods in residences or the wrongful use of pesticides. Stored-product forensic entomology focused on commercial products that had been infested—such as maggots in candy bars or spiders in tissue paper (Catts & Goff, 1992). While each of these forms of forensic entomology have their application in modern day law and criminal justice, the form of forensic entomology that is most popularly applied is the third form already described here and also more accurately known as mediocriminal forensic entomology.
It is this latter form that has the most utility in crime scene investigations. How is it advantageous to today’s crime scene investigators? As Joseph, Mathew, Sathyan and Vargheese (2011) note, “by studying the insect population and the developing larval stages, forensic scientists can estimate the postmortem index, any change in position of the corpse as well as the cause of death” (p. 89). In other words, forensic entomology helps investigators better understand what happened, where it happened, when it happened and how it happened, when they are trying to piece the evidence together and solve a murder, rape, trafficking incident, abuse case, or some other form of crime in which insects and anthropods can help to tell the story.

Knowing about how insects and anthropods feed and nest is crucial, however—which is why the field of entomology is necessary. Forensics would not be the same had entomologists not first began undertaking the study of insects and anthropods in earnest in the 19th and 20th centuries. It was their studies that helped others better understand the crimes of the modern era.

The development of entomology is crucial to understanding crime scene evidence and especially gauging the length of time a cadaver has been a specific place. Without forensic entomology investigators would be handicapped—only able to use medical instruments and measures—such as examining the extent to which rigor mortis has set in, an approach only helpful for pinpointing the time of death a day or two after it has occurred. For cadavers discovered days or weeks after death, medical measures are useless—but scientists who understand nature and in particularly the role that insects and anthropods play in the decomposition process can help stitch together the clues: “by calculating the age of immature insect stages feeding on a corpse and analyzing the necrophagous species present, postmortem intervals from the first day to several weeks can be estimated”—a much more robust approach to understanding the evidence than applying mere medical science (Amendt, Krettek & Zehner, 2004, p. 51).

How Entomology Has Affected the Field of Forensics

Greenberg (1985) states that when examining a corpse an understanding of entomology with…