READ: Entomology

Forensic Entomology

Forensic Entomology

Entomology is the study of insects. Forensic entomology is the study of how insects can be used in a forensic investigation. Insects are most often used to help determine the post mortem interval for a body that is decomposing, but they can also be used in other aspects of an investigation such as determining where a person has been.

One of the most common insects that forensic entomologists use is the blowfly. Blowflies are attracted to dead animals and are necrophagous, meaning that they eat dead animals. There are many different species of blowfly, but they are often metallic blue or green in color. Blowflies are attracted to the smell of a dead body and will typically arrive at the body within the first 24 hours. Once flies have found the body they will lay eggs. The eggs will hatch into maggots the next day. The maggots will eat the body and continue to grow and develop until they form a pupae. A pupae is a hard covering somewhat like a cocoon. Inside the pupae they develop into an adult fly. The life cycle is outlined below.

Day 1 - Blowflies arrive and lay eggs. Day 2 - Maggots hatch and begin eating. Days 3-5 - Maggots go through 3 stages of development. Days 6-12 - Maggots form a pupae. Day 14 - Adult flies emerge from the pupae.

This process takes about 2 weeks, but it is also affected by changes in temperature and weather, so these factors must be taken into account when making an estimation. Depending on where the flies are at in their life cycle the PMI can be estimated. Other insects are also involved with a dead body such as beetles and moths depending on the stage of decomposition. Forensic entomologists study many different types of insects in order to investigate the time of death. 

Click HERE to view another image of a fly life cycle.

Other Specialties in Entomology

There are several areas within forensic entomology that involve different types of crimes. Click on the link below and read the article to learn more about these areas. 

Click HERE and read the article.