There’s a secret “human body farm” in the bush just outside of Sydney where researchers have captured footage of dead bodies moving. Alyson Wilson, a researcher at the Australian Facility for Taphonomic Experimental Research (AFTER), used time-lapse cameras to film the decomposition of a donor body in half-hour intervals over 17 months, the ABC reports. And while her observations are yet to be published in a peer-reviewed journal, it’s thought that they could have significant implications for how police and forensics authorities investigate deaths.

"What we found was that the arms were significantly moving, so that arms that started off down beside the body ended up out to the side of the body," Alyson said. "One arm went out and then came back in to nearly touching the side of the body again."

While some slight movement was to be expected in the earlier stages of the decomposition process, the fact that movement continued for the duration of 17 months was surprising. Alyson suggested that the corpse’s motion could have been a result of shrinking and contracting as the body’s ligaments dried out.

It’s scenarios such as these that AFTER was set up to investigate: the specifics of human decomposition under a variety of conditions that replicate crime scene scenarios. Whatever the cause, the fact that an undisturbed body can move at all could be a breakthrough for crime scene investigators—given those investigators usually assume that the position a body was found in was the position it died in.

"This research is very important to help law enforcement to solve crime and it also assists in disaster investigations," Alyson said. "It's important for victims and victims' families, and in a lot of cases it gives the victim a voice to tell their last story."

Dr Xanthe Mallett, a forensic anthropologist and criminologist who supervised the study, said she was “amazed” at how much the body moved in the footage, and reaffirmed the potential importance of such observations in relation to future crime scene investigations.

"What isn't known is that the body moves as part of the decomposition process and it's the first time that it's been captured, as far as I know," Dr Mallet said. "I think people will be surprised at just how much movement there was, because I was amazed when I saw it, especially how much the arms were moving. It was astounding."