Student Guest Post: Michael Monzon on Six-Legged Witnesses - Using Insect Evidence to Add Context to Archaeological Investigations

Michael Monzon is a PhD student in the Department of Entomology at Rutgers - New Brunswick.  Michael is in the early stages of examining soil recovered from the body cavities of individuals recovered from Arch Street to see which, if any, insect remains are present and can be identified.  This article is the first in a two-part series on the intersection of Forensic Entomology and Archaeology.

Six-Legged Witnesses: Using Insect Evidence to Add Context to Archaeological Investigations

By Michael Monzon, Rutgers - New Brunswick

Archaeoentomology is an interdisciplinary specialty where forensic entomology intersects with archaeology. Forensic entomology is itself a field under the umbrella of Entomology, the division of biological science dedicated to the study of arthropods. The most recognizable group of arthropods is insects. Arthropods are animals in the phylum Arthropoda that have both segmented legs and a chitinous exoskeleton. Aside from insects (arthropods with both three pairs of legs and three body segments), other arthropods include spiders, centipedes, lobsters, and horseshoe crabs. A wide range of animals fall within the classification of Arthropoda.

Forensic entomology is the application of insect ecology to legal questions and cases (Byrd, 2010). Forensic entomologists often collect, process, and interpret insect evidence for a third party. The third party is typically some form of law enforcement but it often varies. Forensic entomology itself can be further divided into sub-disciplines. These sub-disciplines are usually classified as medicolegal forensic entomology, urban entomology, stored products entomology, and cultural heritage entomology with forensic agricultural entomology sometimes having its own delineation. Many areas of forensic entomology overlap each other in various ways.

Medicolegal forensic entomology is the form of forensic entomology most visible in popular culture. Many people may be familiar with the image of an entomologist removing maggots from a homicide victim. Once remains reach ambient room temperature a medical examiner may seek the aid of a forensic entomologist in determining a Post Mortem Interval, or PMI (Campobasso, 2002). This can most simply be interpreted as how long insect evidence has been at a set of remains. Determining the PMI may be the key piece of information that allows the medical examiner to qualify the time of death. Many insect species’ rates of development are closely tied to the ambient temperature of their environment. By identifying the insect to the species level, collecting accurate environmental evidence/data, and observing the insect development a forensic entomologist is able to use algorithms to work backward until the most likely time the insect arrived (Byrd, 2010). In some instances correct application of forensic entomology techniques have been able to render the PMI down to a specific hour. Other ways medicolegal forensic entomology may be used is in cases of neglect or abuse (Benecke, 2001) (Benecke, 2004).

Within the context of forensic entomology, urban entomology most often deals with questions of public health and pest management. For example an entomologist may be asked to determine if a landlord has allowed an insect infestation to become a public health danger through negligence in pest management. In this case the entomologist may begin by inspecting the structure, gathering evidence, and analyzing the pest management/extermination records. Stored products entomology primarily concerns itself with determining how or why an insect infestation occurred in a grocery store, food processing plant, or a wide array of situations where citizens purchase goods infested with insects. Forensic agricultural entomology typically looks at specific cases of animal abuse or may use insect evidence to answer a question about pesticide use/toxicity.

Cultural heritage forensic entomology may be used to assist customs officials in making determinations about a potentially trafficked artifact. Insect evidence associated with a specific artifact or heritage piece may be able convey a wide array of information such as its place of origin (Byrd, 2010). Extrapolated and applied to artifacts and cultural heritage sites in situ, every aforementioned forensic entomological practice and technique is able to add valuable data to archaeological investigations. Archaeoentomology seeks to answer questions of the past and is therefore not a proper forensic science due to the lack of legal applications. What archaeoentomology seeks to do is bring together all the appropriate techniques for a given investigation. These techniques are applied to the site in the same manner a forensic entomologist would approach an open case to the best the situation allows (Byrd, 2010).

This can take many forms aside from just analyzing the condition of deaths in the ancient world. An ancient granary uncovered in Egypt yielded evidence of stored product insect pests (Panagiotakopulu, 2001). Once insect evidence is identified to the species levels it can be contrasted with the modern stored products pests of the area. Just as studying historical events informs future societal decisions, observing historical pest infestations can inform pest management decisions in the future. An analysis of a mummified dog revealed ectoparasites such as the brown dog tick Rhipicephalus sanguineus and fly puparia give more insight into the obstacles with keeping domesticated animals in the ancient world (Huchet, 2013).

As contemporary carrion is a dynamic ecological environment that hosts successive waves of insect populations, ancient remains often contain a robust assemblage of insect evidence. The specific analysis of insect evidence associated with death in an archaeological or historical context is referred to as funerary archaeoentomology (Huchet 2014). In some cases such as an excavated burial mound in South Dakota, insect evidence was able to narrow down the seasonality of burial (Gilbert, 1967). The second article in this series is dedicated specifically to funerary archaeoentomology and how it fits into the broader practice of forensic entomology.

At its core archaeoentomology is ecological analysis of ancient or historical sites through the application of forensic entomological techniques. Archaeoentomology brings together a wide range of practices with the goal of preserving and contextualizing cultural heritage. The synergy of the various modern applications is what makes archaeoentomology possible.

References:

Benecke, M., Josephi, E., & Zweihof, R. (2004). Neglect of the elderly: forensic entomology cases and considerations. Forensic Science International, 146, 195-199. https://doi.org/10.1016/j.forsciint.2004.09.061

Benecke, M., & Lessig, R. (2001). Child neglect and forensic entomology. Forensic Science International, 120(1-2), 155-159. https://doi.org/10.1016/S0379-0738(01)00424-8

Byrd, J. H., & Castner, J. L. (Eds.). (2010). Forensic Entomology: The Utility of Arthropods in Legal Investigations (2nd ed.). New York: CRC Press.

Campobasso, C. P., & Introna, F. (2002). The forensic entomologist in the context of the forensic pathologist's role. Forensic Science International, 120(1-2), 132-139. https://doi.org/10.1016/S0379-0738(01)00425-X

Gilbert, B., & Bass, W. (1967). Seasonal dating of burials from the presence of fly Pupae. American antiquity, 32(4), 534-535. https://doi.org/10.2307/2694081

Huchet, J.-B. (2014). Insect remains and their traces: Relevant fossil witnesses in the reconstruction of past funerary practices. ANTHROPOLOGIE, 53(3), 329-346.

Huchet, J.-B., Pereira, G., Gomy, Y., & Philips, T. K. (2013). Archaeoentomological study of a pre-Columbian funerary bundle (mortuary cave of Candelaria, Coahuila, Mexico). Annales- Societe Entomologique de France, 49(3), 277-290. http://dx.doi.org/10.1080/00379271.2013.845474

Huchet, J-B., Callou, C., Lichtenberg, R., Dunard, F. (2013). The dog mummy, the ticks and the louse fly: Archaeological report of severe ectoparasitosis in Ancient Egypt. International Journal of Paleopathology, 3 (2013) 165– 175. DOI: 10.1016/j.ijpp.2013.07.001

Panagiotakopulu, E. (2001). New Records for Ancient Pests: Archaeoentomology in Egypt. Journal of Archaeological Science, 28(11), 1235-1246. https://doi.org/10.1006/jasc.2001.0697