Decomposition processes of dismembered pigs (Sus scrofa domestica) inside plastic bags in Santa Marta, Colombia

Abstract

Forensic taphonomy utilizes the techniques of anthropology and archaeology to investigate the factors and processes affecting human remains. It also relies on disciplines such as forensic entomology—the study of insects associated with a dead body—to determine the post-mortem interval (PMI). This research documented the decomposition process of four pig carcasses (Sus scrofa domestica) in a fragment of tropical dry forest located at the University of Magdalena. Three of the pigs were dismembered, placed in plastic bags individually and randomly, while one undisturbed carcass was left in the open air. Sampling was conducted daily for 15 days, every five hours, recording body and ambient temperatures, as well as the relative humidity of the site. Insects were collected using entomological nets and stored in fully labeled jars containing 70% ethyl alcohol. Analysis of the samples provided a chronosequence of insects of forensic importance under different environmental conditions, documenting the timings and changes in the stages of decomposition to determine the PMI in each case. It was observed that the decomposition of the pig parts contained in bags was faster than that of the control pig, despite the latter being exposed to the open air, which facilitated insect access. It is concluded that the decomposition process of a carcass varies according to environmental and climatic factors, physical agents, causes of death, and post-mortem alterations. This information is important for clarifying medicolegal investigations as it helps to establish the PMI in bodies found in similar places and conditions.