D3253: Effects of different coverings on insect succession and growth, and the implications in forensic casework

The process of decomposition includes five general stages that depend on physical as
well as environmental, and human factors. When bodies are disposed of, they often are not left without clothes, or some other coverage type. Often in crimes, plastic bags are used as a disposal tool. These coverings can alter the environmental factors of the micro-environment such as temperature, humidity, and light. Decomposition is heavily influenced by insect succession, or the pattern in which insects arrive at the scene, starting with species of flies and ending with species of beetles. Given that covering type may affect the insects ability to colonize, two experiments were carried out looking at the effects of black and clear contractor bags as well as organic and synthetic fabrics. Fetal pigs were placed into one of the covering types and allowed to decompose in consistent conditions in order to determine the difference each covering would have on insect succession. The study site was visited 3 times a day to account for circadian rhythms of the insects, and insects were collected and identified. Results showed differences in both the rates of decomposition and the insect succession rates as well as representing species between the treatment groups. Additionally, a notable difference in the insect growth rates was seen between treatments, specifically between the different contractor bags compared to the control. The results of this study adds additional knowledge to the field of forensic entomology and should be considered when calculating the minimum post mortem interval.