Another interesting aspect of Forensic Science is Forensic Entomology. Forensic entomology is the use of insects in helping solve legal investigations. Insects and their larvae seen in a crime scene can help determine the time of death, detection of abuse among children and the elderly, blood spatter pattern analysis, probable path of an automobile and many more.
We should not underestimate insects. They have been here for more than 250 million years and have developed and evolved to be what they are today. Different insects have different life cycles or ways of developing or maturing into an adult. They could either undergo complete or incomplete metamorphosis.
Even with their small size, they can help forensic entomologists and forensic investigators in solving crimes.
The article tackles the many uses of insects in solving a crime. Ever seen Grisham in CSI Las Vegas examining and studying insects in decomposing victims? Insects aid forensic investigators in determining the time of death of a victim based on the developmental stage of the insect found in the decomposing body. Forensic entomologist aid the medical coroner in determining the probable time of death based on the “Time since colonization” data they made.
Forensic entomologist use forensic microscopes in examining larval length, larval weight, and species succession. Data on these factors aid the forensic entomologist in making their estimates and results.
Forensic microscopes also help in comparing and linking insects found in the victim or in the crime scene with the suspect. Forensic microscopes are used in examining fingerprints, bullet shell casings, hair, fibers, insects and other particles collected as evidence.
Egg laying habits of flies can determine whether the corpse died outside, inside, or was moved from outside to inside or vice versa. Forensic entomologists are familiar with the different egg laying pattern and characteristics of a variety of insects.
Victims of rape and abuse can also benefit from forensic entomological evidences. When a person is under stress (e.g. being raped or abused), the person typically excretes urine or feces. There are insects that are attracted to urine or fecal matter. The presence of these insects can help provide clues before, during, and after the crime was committed.
Insects that suck blood from their victims can also provide serological data. Forensic entomologists can collect blood from these insects and examine the blood sample using
forensic microscopes and then forwarding the sample for DNA studies.
Toxicological studies can also be made on the blood samples collected on the insects that have been foraging the corpse. Blood and urine that are usually needed by a toxicologist are sometimes not available when the corpse is already “eaten” by these insects. In lieu of the victim’s blood and urine, the insect’s tissue samples are collected and studied because toxins accumulate from the tissue, blood and urine that they ate from the humans.
The next time you see insects or larvae on a victim, do not grimace. Be thankful that these little creatures are there to clue in forensic entomologists and investigators in solving the crime puzzle.
