How the little critters can help Forensic Entomology How the little critters can help

Insects are predictable Because we can observe the behavior of insects, we can establish a timeline that can indicate approx. time of death First, the general effect of time on a body: Fresh: immediately following death and before bloating. Bloated stage: gases produced by decomposition within the body cause it to swell. Active decay: larvae penetrate the abdomen, causing deflation Advanced decay: majority of internal tissue lost, other internal elements beginning to liquefy. Dry remains: soft tissue lost, leaving skin, bone and cartilage.

It’s hard to establish an exact time that is standard Climate concerns: Temp Moisture Location Types of indigenous insects differ area to area

General Life Cycles are Important Egg Larva Pupa Adult Predictable times

Other insects Dermistids Roves Silphids Scarabs Skin Beetles Carrion Beetles Late Stages

Points of interest: Myiasis=> Where maggots feed on living material Dermistid Beetles used to clear flesh from skeletons

Some limiting factors: Time of day- Flies don’t lay eggs at night Geography Different climates- different insects Season Especially in N.E.(Temperate zones) Microclimate Was the body in the sun? Habitat Urban locations vs. City

Bodies in buildings Burial Bodies in water Wrapping Different accessability Greater flies, less beatles Burial Denies surface access (flies) Bodies in water Submerged- only aquatic insects Partial- flies & aquatics Wrapping Could restrict access of some Flies access anyway

Scavenger activity Burning Actually doing same job macroscopically Alters A LOT Where, how, insects Burning High temps offset normal measures Cracked skin allowed easier access Body NEVER entirely consumed

In Summary: Insect determination is a science that must be known only by investigation in that region Many variables must be controlled Predictable but must establish COMPARISION How is this done?- Experimentation!!