#39 Creepy Crawlies: Intro to Forensic Entomology I

Aiza Jamil
Feb 1
2 min read

Hello, and welcome back, folks, to another episode of STEM on the Streets! If you are new here, my name is Aiza, and this is my partner, CAI (crime AI). Together, we stroll through the criminal-ridden streets of STEM!

If you haven't read the previous episode, click on the button to read it!

Click Me

What is Forensic Entomology?

Did you ever think that the creepy crawlies and the roaches that haunt bathrooms would ever help solve crimes? Honestly, I didn’t either. Forensic entomology is the application of entomology, which you could say is insect science, in criminal and legal investigations. Basically, investigators use insects and other arthropods as evidence to determine what happened at the crime scene. It often helps with how long a person has been dead, if the body was moved, and other details of a suspicious death. It can be used in other things, like investigating food contamination and civil dispute involves pests.

Why Insects?

Insects are amongst the first organisms to arrive at a decomposing body (if you have ever seen roadkill or a dead pigeon, you must have seen the flies around it), and different species arrive in a predictable sequence as the decomposition progresses. Forensic entomologists collect and identify these insects and also study their life stages (like maggots and larvae) to determine the post-mortem interval- basically, the time since death.

The History

Even though people have seen and noticed insects near dead bodies for centuries, one of the earliest uses of insects to solve a legal problem was actually in the 13th century, in China, when a murder investigator used fly behaviour to identify a suspect. It was quite an interesting incident, as the sickle that was used to kill the farmer attracted the flies. Then, later on in the 18th-19th centuries, entomologists in Europe began to systematically observe insects on corpses and laid the foundations for the modern discipline.

How It Works

In a practical forensic investigation, specialists begin by collecting specimens from different places on the body and the surrounding soil. Then they identify the species of insect present ( such as different types of flies and beetles) and record the developmental stage (egg, larva, pupa, adult). With the information on the developmental stage, they can use known growth rates and environmental data to back-calculate how long the insects have been there, giving an estimate of time since death.

Types of forensic entomology

There are different subfields within forensic entomology: