Yarramundi's Australian Facility for Taphonomic Experimental Research (AFTER) site makes important discoveries about human cadaver decomposition

The AFTER site - which stands for Australian Facility for Taphonomic Experimental Research - is the only facility of its type in Australia, and was launched by the University of Technology (UTS) to observe and research the decay of human corpses.

Dr Maiken Ueland, postdoctoral research associate and deputy director of the project, said there are currently 74 human bodies on the site in various stages of decomposition, and the team did the best they could to make every body donation count.

One of the first discoveries they made was about pig carcasses, and the fact that they behaved differently from human bodies when decomposing.

"Pigs have traditionally been used a lot in taphonomic research, but we didn't know if they were true models for humans," Dr Ueland said.

"We were using pigs a lot before humans, so we wanted to see if they behaved in the same way. We followed their decomposition over different seasons, and what we found was how they were decomposing visually was quite different.

"Pigs decomposed very 'textbook-like' - the whole body at the same stage. But humans have 'differential decomposition', where one part of the body, say, the head, would look a lot more decomposed than, say, another body part like the leg.

"So it's much more challenging with humans to find the time of death."

Another finding was to do with the odour of the bodies, which the team tracks and analyses back in their lab at UTS in Sydney.

"We found that the odour was very different between pigs and humans, which means we can't use pigs to train cadaver detection dogs," she said.

Dr Ueland said one of the most important findings the team had made was to do with mummification - which is when the tissue becomes dark, dry and leathery, and prevents the decomposition process.

"We saw that happening a lot for the human remains. That will influence the time-since-death estimate," she said.

"We used to think mummification of tissue types happened in very specific environments, but in Sydney we're seeing it happens at all different seasons and times of year.

"That was quite shocking for us when we saw it - we were not expecting that whatsoever."

Apart from UTS, the AFTERS project has 16 other partner organisations, including other universities, forensics agencies, and law enforcement agencies.

There are numerous studies going on at the site, including one by an honours student from Queensland, who has been tracking the bodies via timelapse camera, which has revealed different parts of the bodies - including facial features and hands - 'move' during different stages of decomposition, as the body mummifies and the ligaments dry out.

Knowledge like this could be significant in unexplained death investigations.

Dr Euland said research at the AFTER site is multi-faceted.

"We do a lot of work in three different areas," she said.

"Firstly, how we can better find missing persons - for example a bushwalker who has gone hiking and hasn't found their way back, as well as someone who has gone missing in a homicide or mass disaster.

"We're using different types of tools and instruments in the field to find out how we can use the scent to track them, and also using drones to track the heat signals coming off the body.

"Another big area - a crucial area for any investigation - is finding the time of death.

"And the third big area is the identification phase.

"We've already done quite a bit of case work and we've been able to assist with a number of cases."

Dr Maiken said the team values the contribution from all its donors, maximising every donation with collaborative research.

"Every donation is such a valuable gift," she said. "Without these contributions we can't do any of the research we're doing."

"We're already seeing great results and we've been able to help the police directly with case work."

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