Marine life assists forensic efforts

Jun 24, 2014 by Lily Yeang
She says it is important that aquatic organisms continue to be studied in forensic science so cause of death in a water-based crime scene can be reached more efficiently. Credit: Paulo Ordoveza

Aquatic organisms can play a role in explaining events surrounding the presence of human remains found in a water environment, according to a University of Western Australia expert.

UWA Centre for Forensic Science forensic biologist Paola Magni says can help to determine how long have been in the and the cause of death.

"A crime scene may occur in a water environment as a result of natural causes, homicide, or mass disasters," Dr Magni says.

"But only a few studies exist in regard to crime scenes in an and only a small number of experts have the training and the expertise to investigate such cases."

Dr Magni says the identification of the time-since-death of a body submerged in water has become one of the most difficult dilemmas facing forensic experts.

She says the identification of organisms that colonise the body during death can help experts determine how long the remains have been floating, as well as its origin within the water environment.

"Floating remains can be colonised both on the surface exposed to air [generally by adult insects that lay eggs or larvae on them] and on submerged parts of the body [by insects and other arthropod larvae which use the remains as shelter or a food source]," she says.

Dr Magni says detecting the presence of diatoms or bacteria in internal organs such as the heart, brain and bone marrow can help to determine a cause of death by drowning.

"If drowning occurred in freshwater or saltwater, chemical compounds and water microorganisms [diatoms, bacteria] diminish in the left side of the heart as a consequence of the absorption of water from the lungs into the circulation [system]," she says.

"Furthermore, in seawater, haemoconcentration [decrease in plasma volume, increase in volume] is found because of the loss of fluid from the blood into the alveolar spaces.

"This takes place in order to establish the osmotic equilibrium altered by the diffusion of salts from seawater into the bloodstream."

Dr Magni says a large presence of aquatic or semi-aquatic organisms in a particular part of the body can also suggest the presence of a wound that could be one of the causes of death.

She says it is important that aquatic organisms continue to be studied in so cause of death in a water-based can be reached more efficiently.

Explore further: Using blowflies as 'meth detectors'

add to favorites email to friend print save as pdf

Related Stories

Carnivorous water rat discovered in Indonesia

Jun 18, 2014

(Phys.org) —Jacob Esselstyn, curator of mammals at LSU's Museum of Natural Science, was part of a research team that discovered a carnivorous water rat in central Indonesia. The species was previously known only to local ...

Dutch scientists crack fingerprint dating riddle

Jun 04, 2014

Criminals' days may be numbered after Dutch forensic experts discovered how to accurately date fingerprints, a breakthrough that could one day let police date crime scene prints from years ago.

Recommended for you

Extinctions during human era worse than thought

1 hour ago

It's hard to comprehend how bad the current rate of species extinction around the world has become without knowing what it was before people came along. The newest estimate is that the pre-human rate was ...

Robotics to combat slimy pest

4 hours ago

One hundred years after they arrived in a sack of grain, white Italian snails are the target of beleaguered South Australian farmers who have joined forces with University of Sydney robotics experts to eradicate ...

Migratory fish scale to new heights

5 hours ago

WA scientists are the first to observe and document juvenile trout minnow (Galaxias truttaceus Valenciennes 1846) successfully negotiating a vertical weir wall by modifying their swimming technique to 'climb' ...

Frequent fire and drying climate threaten WA plants

5 hours ago

Murdoch University fire ecology experts have warned that in Western Australia's drying climate, many of the plant species which contribute to the stunning wildflower displays north of Perth may need 50 per ...

User comments : 0