Name: 法医昆虫学者が明かす、昆虫が不審死の謎を解く方法 | WIRED Japan
Uploaded: 2025-01-28T09:20:13.000Z
Duration: 6 min 16 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

Participle clauses

It's a florid fly, also known as a coffin fly.

Flies like these provide crucial evidence in solving mysterious deaths.

With my job as forensic entomologist, I use these tiny witnesses to give justice to victims.

Wired spoke with Dr. Pola Magni to understand how insects can be used to help solve suspicious deaths.

The forensic entomologist is one of the many experts that work at the crime scene in order to provide more information to the course of an investigation.

The post-mortem interval, or PMI, is considered the time since death.

It is pretty much the time between the moment of death to the identification of a dead body.

They can provide an alibi to somebody or destroy an alibi for somebody else.

The victim was a female that was found wrapped in a blanket and covered by a carpet.

The pathologist could not estimate a time since death.

Typically, the pathologists work within the 72 hours after death.

After this time, nature takes over and the typical signs of death, the rigor mortis, algal mortis, liver mortis, cannot be used anymore.

But this is exactly the perfect time for the insects to colonize the body and start what we call the biological clock, that is what forensic entomologists use to investigate and estimate the time since death.

Estimating the PMI in this case relied on analyzing the life cycle of flies.

Their development from egg to adult can be predicted based on environmental conditions.

Insects grow faster or slower based on the environmental temperature.

And there were maggot masses active on the body.

So if outside there were 25 degrees, inside of the maggot mass nearly 28 degrees.

My job in that case was to collect the maggots, considering the species and temperature, to backtrack the time since death.

There was already somebody suspected of this murder, but the insects were given different information, giving an alibi to the suspect.

The time since death was around the same time of a long exchange of messages and phone calls with a certain person, help the investigators investigate specifically on someone else, ask the right questions and close the case.

Some insects are interested in the fresh decomposition, some highly decayed and some when body is just bones.

Based on the kind of insect I can find, I can understand from how long the body is there.

So my job was to participate into the investigation if this person was dead since the last time he was seen alive or if there was something going on.

The body was nearly mummified by the bugs, and specifically one type of bugs that are called the larder beetles created a very strange structure that were looking like threads on the body.

When the body is mummified or when I find just bones on a very old body, I use another technique that is called the successional waves methodology.

Successional waves refers to the different types of insects that are found at different stages of decomposition.

Using this method allows forensic entomologists to estimate PMI for older cases.

The case of the forgotten man was pretty complex because there was an association of different types of insects.

We had to identify which insects were belonging to the body and which ones to the house.

All of these insects were giving us information about how many successional waves had passed by to estimate the time since death.

We realized that the body was laying in the place where we found it for at least a year and a half.

When we watch CSI or similar TV programs, most of the time investigators found the presence of a body on the ground.

The reality is that the majority of the cases, bodies are found contained in something.

We consider that as limited access environment.

Insects have a physical impediment to reach the body, but they don't give up.

Insects really try their best to reach the body.

Because the body means food, and the body means place for their offsprings to grow and survive.

The low flies will lay eggs on the zip and the female of coffin flies can pass through the zip and reach the body.

So there is this consuming food chain that happens inside of a suitcase that is very interesting because what we find inside is whatever happened before.

So we can find different successions and we can work on that to identify from how long the body is inside of a suitcase.

Despite these cases happen all around the world and pretty often, the research is really scant because it's very difficult to perform such a huge research.

My group of research is developing this to find out how insects can interact with a body during the winter period in suitcases compared to trash cans.

This research will allow us to give more information to investigators if cases like this happen in Western Australia.

Forensic entomology is really holistic from the point of view as a discipline because it considers insects, also has to consider the investigative process and has to combine the information from the insects with the information about the environment, the meteorology and at the specific crime scene.

What I'm trying to do with my work is to use this little piece of nature to give justice to the victim.