BUGS, BONES AND BODIES

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BUGS, BONES AND BODIES

• Anthropology Entomology, and Pathology

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Manner of Death

• The manner in which death occurred is classified
  into five categories natural, homicide,
  suicide, accident, or undetermined, based on the
  circumstances surrounding the incident.

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Stages of Death

• Time of death is often estimated by evaluating
  the stage of decomposition in which the victim
  was found.
• Rigor mortis the medical condition that occurs
  after death and results in the shortening of
  muscle tissue and the stiffening of body parts in
  the position they are in when death occurs.

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• Livor mortis the medical condition that occurs
  after death and results in the settling of blood
  in areas of the body closest to the ground.
• Algor mortis postmortem changes that cause a
  body to lose heat.
• Rate of heat loss is influenced by such factors
  such as the location and size of the body, the
  victims clothing, and weather conditions.

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• The general rule is that beginning about an hour
  after death, the body will lose heat at a rate of
  approximately 1 to 1 ½ degrees Fahrenheit per
  hour until the body reaches the environmental
  temperature.
• During an autopsy, other factors can be observed
  that may indicate the time period in which death
  occurred. For example, the amount of food in the
  stomach can help to estimate when a persons last
  meal was eaten.

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Stages of Bodily Breakdown

• Initial decay externally, the corpse appears
  much as it did in life, but decomposition has
  begun due to the actions of bacteria,
  protozoans, and nematodes already present in the
  body when it was alive.

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• Putrefaction Gas formed by the activity of
  organisms within the body cause it to swell and
  smell.

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• Black putrefaction a bit of a misnomer,
  actually, as the characteristic discoloration of
  the flesh accompanying this stage may be blue,
  green, purple, brown, or black. The swelling of
  the previous stage collapses again as that gas
  begins to escape. The swelling decreases, but the
  smell increases dramatically.

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• Butyric fermentation tissues and organs have
  become fluid, fluid has escaped by a variety of
  means, and now the body begins to dessicate (to
  dry out). Mold usually covers some or all of the
  exterior. A different odor not good, but not as
  knock you over and send you gagging as the
  previous one is noticeable.

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• Dry decay not mummification, but a slow process
  of continuous decay, during which time the
  tissues continue to rot, dry out, and shrink
  until skeletization has occurred.

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Forensic Pathology

• Forensic pathology involves the investigation of
  sudden, unnatural, unexplained, or violent
  deaths.
• Usually medical examiners or coroners.
• Primary role is to determine cause of death.
• Autopsy the medical dissection and examination
  of a body in order to determine the cause of
  death.

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Forensic Anthropology

• Forensic anthropology is a specialty that is
  concerned primarily with the identification and
  examination of human skeletal remains.
• Skeletal bones are remarkably durable and undergo
  an extremely slow breakdown process that will
  last decades or centuries.

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• An examination of bones may reveal their origin,
  sex, approximate age, race, and skeletal injury.

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Forensic Entomology

• The study of insects and their relation to a
  criminal investigation.
• Traditionally used to determine time (or date) of
  death.
• Insects contribute to establishing suspect
  movement in cases where there are no bodies at
  all, the point of origin in many illegal drug
  caches, and the path of stolen automobiles as
  they get handed off in organized car rings.

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All About the Bugs

• Insects are never born in fully developed adult
  form. Instead, theyre dumped into the world
  either as eggs or larvae.
• In either case, each species of insect
  progresses through the other stages of its life
  cycle at predictable times.

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Blowflies

• Life cycle progresses from egg to first instar (a
  stage of larval growth, usually determined by
  maggot size and how often it has shed its skin)
  larvae, to second instar larvae, to third instar
  larvae, to prepupae, to pupae within puparium,
  and on to imago.
• The length of each stage is dependent on
  environmental conditions.

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• Before determining how long a body has been dead,
  the entomologist must first have a good idea of
  when the first blowflies arrived and laid eggs on
  the body. In the case of blowflies, the preferred
  time is approximately two days after death.
• Blowflies are not native to all areas so other
  species are also studied so that experts can
  discover their cycle.

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Other Bug Notes

• An entomologist must be familiar with the insects
  of the region where a body was found or where
  death occurred - not necessarily the same place.
• Photographs should include adult insects of all
  species in the vicinity, evidence of insect
  activity in any standing blood, and the remains
  of insect activity.
• Body parts showing insect infestation need
  photographing before the body is removed.

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• Air temperatures at ground level, about 5 feet
  high, and ground surface temperatures under the
  body should be recorded.
• Live-specimens, remains, and preserved samples of
  all insects should be collected.
• Documentation of the scene must be included.
• Lack of insects or nonnative insects should also
  be recorded.
• Weather data allows entomologists to adjust life
  cycle equations.