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How the little critters can help
Forensic Entomology How the little critters can help
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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.
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It’s hard to establish an exact time that is standard
Climate concerns: Temp Moisture Location Types of indigenous insects differ area to area
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General Life Cycles are Important
Egg Larva Pupa Adult Predictable times
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Other insects Dermistids Roves Silphids Scarabs
Skin Beetles Carrion Beetles Late Stages
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Points of interest: Myiasis=> Where maggots feed on living material
Dermistid Beetles used to clear flesh from skeletons
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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
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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
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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
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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!!
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