Groundbreaking UCT study on decomposing pigs could help investigators identify human remains

We all know that crime is out of control in our country, and forensic investigators are often overburdened when it comes to cases of murder.

Now, help with identifying human remains could be coming from an unexpected source - the decomposing bodies of pigs.

A groundbreaking study conducted by the University of Cape Town used porcine carcasses as proxies for human bodies.

Sara-Jayne Makwala King finds out more from Kara Adams, who was involved in the study as part of her PhD dissertation at UCT.

Adams explains that South Africa's legislation prohibits the use of donated human bodies for decomposition research, which is allowed in some countries.

Pigs are generally used instead, because of their anatomical similarities with humans and the similar processes of decay the two species go through.

The animal carcasses in the UCT study were further 'dressed' in specially tailored clothing, to mimic the usual state human bodies are found in at crime scenes.

"Pigs provide a great source of baseline data in situations where no data previously existed or humans can't be used. No data had previously existed in quantifying natural mummification here, and we were the first globally to do this."

"Of course we dressed the pigs, and the colouring we chose was noted from what was commonly seen in real cases. Each piece of clothing was tailored to fit the pigs - we just wanted to be as forensically realistic as possible, ensuring that the clothing would fit the pigs as it technically would fit a human."

Kara Adams, Post-doctoral Researcher - UCT

The researchers' main objectives were to see how clothing and also scavengers affect the decomposition rate of bodies, as well as to examine the mummification that happens.

Single, clothed pig carcasses were placed in two forensically significant locations in Cape Town during the summer and winter months.

Delft was chosen as a peri-urban habitat, and Rosebank as a suburban habitat.

Previous research on high crime areas had shown these as the types of locations where bodies are typically found.

The study provided valuable insights, Adams reported in a UCT report-back.

"Desiccation in summer appeared to follow an exponential decline and temperature was the most influential environmental factor."

"By understanding the typical decomposition rates of clothed versus unclothed remains in specific environments, using pigs as a model, forensic experts can more accurately estimate the time since death for human decedents."

"This data collection demonstrates the potential of using accumulative degree days and moisture content to estimate the post-mortem interval.”

Kara Adams, Post-doctoral Researcher - UCT