Not Your Ordinary Road Kill: Forensic Entomology

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Not Your Ordinary Road Kill Forensic Entomology

• Kathy Mirakovits
• Portage Northern High School
• Forensic Science IB Physics Teacher

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Educational Value of Entomology

• Biology Curriculum Decomposers.
• Natural Progression of Decay Biological Life
  Cycles.
• Forensic Science Curriculum
• Estimation of Time of Death (TOD).
• Mathematics
• Calculations for Time of Death.

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Forensic Entomology

• Application of the study of insects and other
  arthropods to legal issues, especially in a court
  of law.
• Not a popular profession--9 on the Popular
  Sciences List of Ten WORST Science Professions
  in 2008.
• 1st use of insects in crime solving China 1235
  AD

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Life Cycle of the Blow Fly
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Why utilize Blow Fly Life Cycle?

• Arrive soon after death
• -often beat everyone to scene
• Arrive in predictable patterns
• -communities change with decomposition
• Development is predictable
• -based largely on temperature

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colonizationegg laying
feeding maggot
active decay
maggot mass
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Natural Process of Decompositionhttp//www.deatho
nline.net/decomposition/index.htm
Decomposition begins moments after death
continues through a series of physical and
chemical changes over time
Fresh Bloat Decay
Post Decay Dry
1-2 d 2-6 d 5-11 d
10-25 d 25 d
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Pig Decomposition at MSU Conference
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Temperature

• Temperature and time of day are other important
  aspects an entomologist needs to consider.
• Time of Day Most flies are DIURNAL (they do not
  fly at night).
• Temperature Fly life cycle requires warm
  temperaturesin the air, on the body and on the
  ground.

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Fly Eggs
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Maggots

• How to tell a 1st, 2nd and 3rd Stage Instar
  Maggot from each other?
• -mouth at the anterior end
• -breathe at posterior end through the
  spiracles
• -spiracles have slits in them for breathing
• 1st stage instar has 1 slit
• 2nd stage instar has 2 slits
• 3rd stage instar has 3 slits

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Maggot Mass

• A large group of maggots is called a Maggot
  Mass.
• These generate lots of heat (thermal energy) as
  they transform the food energy to energy to grow,
  producing heat as a by-product.
• Maggot mass temperatures can be 20 degrees
  higher than the ambient temperature.
• The heat produced also helps speed up the
  decomposition of the body.

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The Dormant Stage Puparia

• Maggots at the 3rd stage migrate away from the
  bodymigrating maggots.
• The migrating maggots burrow into the soil to
  find a safe place to form the puparia, similar to
  a chrysalis for a butterfly.

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Mathematics ADH/ADD

• Accumulated Degree Hours (ADH)
• Accumulated Degree Days (ADD)
• Used by Forensic Entomologists to calculate the
  Post Mortem Interval (PMI).

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Entomology At Portage Northern

• Body Farm set up.

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Entomology Field Day

• Collect Temperature Readings
• 1. outside temperature 2. temp on the body
• 3. temp under the body 4. temp in maggot mass
• Collect Fly Cycle Specimens
• 1. eggs
• 2. maggots (different instarsall three)
• 3. fly specimen
• 4. migrating maggot
• 5. puparia

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Entomology Field Day

• WEAR GLOVES
• Put name, location onto paper label with PENCIL.
• Put multiple samples in a vial that has ETOH
  (ethyl alcohol) in it.
• Three vials per group Eggs/Maggots/Fly Puparia
• Return vials to classroom for microscopic
  examination.
• Clean up thermometer, forceps.

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...From This
To This...
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Tis The End..

• Entomology Kits Available
• WARDS Natural Science
• Critters on Cadavers Forensic Entomology Lab
  Activity
• 36 V 6232 228.00
• Dr. Neal Haskell, Forensic Entomologist
• Maggots From Murders Kit, Manuals, T-Shirts
• www.maggotsfrommurders.com Kit 68.00 SH

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Questions?

• Contact Information
• Kathy Mirakovits
• kmirakovits_at_portageps.org
• kjmirakovits_at_chartermi.net
• 269-323-5403 (school)
• Summer Workshops?
• visit www.swmses.org/forensicscience