Tiny sea organisms found in centuries-old bones from Western Australian shipwrecks could help forensic scientists solve modern crimes, according to the Perth scientists who discovered them.
Murdoch University forensic scientists Paola Magni and Edda Guareschi discovered minuscule one-celled organisms embedded in the bones and teeth of pig, cow and sheep bones and teeth from shipwrecks dating as far back as 1629.
Dr Magni said the organisms could be used to solve real crimes by identifying where a body went into the water, or even how the person died.
"Because finding the plankton in the bone marrow will tell you that there is a good possibility that this body was drowned when it was alive."
The shipwreck bones had to be sampled using special machines to make slides that could be viewed under an electron microscope.
They were taken from four shipwrecks, including the Batavia, a Dutch East India Company ship wrecked in 1629 on the Abrolhos Islands, west of Geraldton.
Bones were also taken from the Vergulde Draeck (The Gilt Dragon ) which was wrecked near Ledge Point in 1656; the Zeewijk, also wrecked on the Abrolhos in 1727) and the Rapid, and American ship which foundered on Ningaloo Reef in 1811.
Dr Magni said there were multiple ways that underwater life could be used to solve crimes in aquatic environments.
Because the micro-organisms inside the bones are often specific to one area, they could be used to identify where the bones have been.
"If the bones were moved from WA to somewhere else, because of the currents, the tides, or simply somebody moving from place to place, we could actually back track to where these bones were coming from," she said.
The Murdoch University research also made discoveries about how the single-celled organisms affect the spaces inside submerged bones, which can help estimate the time frame of the death.
The scientists also researched the effect that barnacles have on bones, and the chemical changes that happen over time.
Dr Magni said she worked on a case in Italy where plankton found inside the fabric of a suspect's shirt was used in the case against a man accused of killing his girlfriend. The man was ultimately convicted of the crime.
But she said more research was needed to further examine the clues that could be held under water.
"Many crimes happen in water. Aquatic forensics is the discipline of studying crimes that happen in aquatic environments," Dr Magni said.
"The ocean, but also the rivers or even your bathtub.
Dr Magni said the Murdoch scientists were among a small number of teams worldwide who were researching aquatic forensics.
"It's very limited at the moment, it's in infancy," she said.