Skip to main content

Carrion Ecology

Decomposing animal carcasses are nutrient rich resources for many organisms including microbes and insects. Without the decomposing nature of how these organisms metabolize resources, the nutrient cycle would never reach completion and the raw resources that these carcasses represent would be wasted. The investigations in this section delve into the field to decompositional ecology with long-term, multi-scale and novel studies.

In 2013, my lab was actively developing the use of next-generation high throughput metagenomic sequencing to examine terrestrial and aquatic microbial communities and their interactions with insects. We have been quite successful and plan to continue to take advantage of these new tools in multidisciplinary research efforts. As an example of this interest, at the Annual Meeting of the Entomological Society of America my lab organized a symposium called “Rocking Your Connected World: The Importance of Insect Microbiomes”, which attracted high profile entomologists interested in insect microbiomes as speakers. At the Annual Meeting of the American Academy of Forensic Science in February 2014 I co-organized a workshop entitled “Forensic Microbiology: Where Do We Begin?” and a special symposium as part of the Pathology/Biology section called “Microbes”; both drew large, multidisciplinary crowds, including a National Institute of Justice program officer. 

Forensic Applications

During a criminal investigation such as a homicide, a primary goal for investigators to determine the post-mortem interval (PMI), which is defined as the time since death. By establishing an accurate PMI, one can use this information to eliminate or incriminate suspects, and in determining if the body has been moved. If the evidence is available, necrophagous insect succession can be used to determine the PMI. The insects attracted to decomposing organisms follow a predictable pattern of succession and growth during the decomposition process. Dipterans, specifically the family Calliphoridae (blow flies) are the most commonly used insect in determining PMI. By knowing the species-specific growth rate and ambient temperature of the crime scene, researchers can use the largest collected blowfly maggots and track back to the approximate time of blow fly oviposition, which is most often closely related to the time of death.

Our research is collecting specimens to establish a necrophagous insect library for Michigan and providing timelines for the insect succession that will be beneficial to future forensic investigations that have collected invertebrate evidence. Another avenue of our research is looking at the microbial communities and their influence and succession during decomposition. Microbial evidence may eventually become another method used for criminal investigations. With further research into the life cycles and behaviors of these microorganisms, one could use them to help determine PMI, to determine if the body has been moved, and many other applications may exist.