Forensic Entomology
description
Transcript of Forensic Entomology
Forensic Entomology
Bud and Patti Bertino
Forensic Entomology is based on:
• Insect life cycles• Knowledge of length of stage of
development• Predatory food chain on corpse• Gases produced by decomposing bodies
draw insects, not blood• These gases are carbon dioxide,
methane, ammonia and nitrogen
A first ‘wave’ of insects• Usually blow arrive first laying
150-300 eggs on soft tissue lining body openings on corpse• In 1-2 days, eggs hatch and
maggots feed on corpse (1st instar stage)
•Maggots mature through 3 instar stages before forming a cocoon (pupa stage)•About a week later, adult flies emerge
What might effect the accuracy of the time sequence of the life cycle of the blow fly?
Blow fly arrives in less than one minute
Various Types of Maggots
Life Cycle of the Flesh Fly
Second wavecould include:
• Beetles or other insects who feed on blow flies and have a life cycle of their own
• The corpse may really be the origin of a food chain.
How does a food chain work?
How would each of these factors affect time of death estimations?
• Burial• Immersion in water• Mummification• Geographic location
• Temperature & Humidity• Light & Shade• Season• Length of day• Manner of death (Poisons may slow down
decomposition)
Time to get to work!
Forensic examination kit
Project ideas:1. Study the life cycle of a blow fly and
determine the timeline used by forensic scientists.
2. Obtain some liver and grow your own ‘time line’.
3. Search the internet for crimes that were solved through the use of forensic entomology.