Transcript Human Remains - Henry County Schools

Forensic Entomology
Taxonomy
Classification of Things in an Orderly Way
We are interested in the phylum, Arthropoda; class, Insecta; order:
Diptera (flies)
Coleoptera (beetles)
Forensic Entomology
Involves the use of insects and other arthropods to aid in legal
investigations. Entomology is the study of insects.
There are three areas of application:
Insect damage to structures
Infestation of foodstuffs
Insects that inhabit human remains (focus of this chapter)
The Process of Death
Algor Mortis: Body cooling rate
Hours since death =
98.4°F – internal body temperature
1.5
Livor Mortis: skin discoloration caused by pooling of blood
Rigor Mortis: rigidity of skeletal muscles
Temperature of body
Stiffness of body
Time since death
Warm
Not stiff
Not dead more than 3 hours
Warm
Stiff
Dead between 3 and 8 hours
Cold
Stiff
Dead between 8 and 36 hours
Cold
Not stiff
Dead for more than 36 hours
A pathologist estimates time of death from these factors.
The Process of Death,
continued
Stage
Description
Initial or fresh decay (autolysis)
The cadaver appears fresh externally but is
decomposing internally due to the activities of
bacteria present before death (0–4 days).
Putrefaction or bloating
The cadaver is swollen by gas produced internally,
accompanied by the odor of decaying flesh (4–10
days).
Black putrefaction
Flesh of creamy consistency, with exposed body
parts black. Body collapses as gases escape.
Fluids drain from body. Odor of decay very strong
(10–20 days).
Butyric fermentation
Cadaver drying out. Some flesh remains
at first; cheesy odor from butyric acid
(20–50 days).
Dry decay (diagenesis)
Cadaver almost dry; slow rate of decay. May
mummify (50–365 days).
Life Cycle of Insects
Metamorphosis
egg
larva (maggot)
The life cycle of
Musca domestica
pupa
winged adult
Time of Death
Insects arrive at a decomposing body in a particular order
(succession) and then complete their life cycle based on the
surrounding temperature. By collecting and studying the types of
insects found on a body and their metamorphic stage, a forensic
entomologist can estimate the time of death.
Insects of Death
Diptera
First to arrive
Blowflies
Then
Flesh flies
Houseflies
Flies can arrive within minutes. They lay eggs that hatch to
maggots. Maggots feed on soft, mushy body parts. More insects
arrive to feed on the body and each other.
Insects of Death, continued
Coleoptera
In rough order of appearance, from within hours to dry decay:
Rove beetle
Sexton beetle
Clown beetle
Dermestid beetle
Hide beetle
Some beetles feed on the corpse, some on maggots, some on
other beetles.
Variables Affecting
Metamorphosis
Temperature
The higher the temperature (within limits), the faster the growth.
Variables Affecting
Metamorphosis, continued
Habitat
Fly species can vary geographically according to climate,
season, and habitat.
Phormia regina
Lucilia illustris
For example, the fly pictured on the left prefers shade; the one on the
right, sunlit areas.
Other Applications of Forensic
Entomology
Damage to structures, clothing, foodstuffs
Location of wounds on a corpse
Linking suspect to scene of crime
Source of contraband
Type of insects can trace vehicle movement
Presence of drugs in corpse
Collection of Evidence
Human Remains
Human Remains
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Human Remains
Forensic Anthropology
Forensic anthropology is a type of
applied anthropology that
specializes in the changes and
variations in the human skeleton
for the purpose of legal inquiry.
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Forensic Anthropology, continued
A forensic anthropologist may provide basic identification
information on skeletonized or badly decomposed remains.
From a whole bone or part of a bone, the scientist may be able
to determine:
•
•
•
•
•
An age range
Sex
Race
Approximate height
Cause of death, disease, or anomaly
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Human Remains
Osteology
Osteology is the study of bones.
There are 206 bones in an adult human.
Function of bones:
• Provide structure and rigidity
• Protect soft tissue and organs
• Serve as an attachment for muscles
• Produce blood cells
• Serve as a storage area for minerals
• Can detoxify the body by removing heavy metals and
other foreign elements from the blood
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Human Remains
Estimation of Height
The height of a person can be calculated by measuring the length
of certain long bones, including the femur, tibia, humerus, and
radius. Below are the equations used to determine average
measurements for both male and female. (All measurements
are in centimeters.)
Male Height, H
Female Height, H
H = femur  2.23 + 69.08
H = tibia  2.39 + 81.68
H = humerus  2.97 + 73.57
H = radius  3.65 + 80.40
H = femur  2.21 + 61.41
H = tibia  2.53 + 72.57
H = humerus  3.14 + 64.97
H = radius  3.87 + 73.50
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Human Remains
Age Determination
Most accurate estimations are made from:
• Teeth
• Epiphyses or growth plates
• Pubic symphysis
• Cranial sutures: The three major cranial sutures appear as
distinct lines in youth and gradually close from the
inside out.
Investigators always use an age range because of the variation in
people and how they age. The investigator does not want to
eliminate any possibilities for identification.
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Age By Teeth
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Cranial sutures
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Age Determination Using Cranial Sutures
Sagittal suture completely closed
Male—26 or older
Female—29 or older
Sagittal suture completely open
Male—less than 32
Female—less than 35
Complete closure of all three
major sutures
Male—over 35
Female—over 50
Sagittal suture
Lambodial
Coronal
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Age Determination Using Basilar Suture
Basilar suture
Technically known as the
synchondrosis sphenooccipitalis, closes in females
as young as 14 and in males
as young as 16. If the suture is
open, the individual is
generally considered to be 18
or younger.
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Age Determination
In long bones, the diaphysis, or shaft, makes up most of the bone’s
length. The epiphyses are found at the ends of the bones; their
function is to allow for growth. The epiphyses are good places to
look for changes in estimating age. Though all people are different
and grow at different rates, there are similarities that allow for
generalizations in estimating age.
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Definitions
Stage 1: no epiphysis (the growth plate has not formed yet)
Stage 2: non-union; the epiphysis and bone are separate
Stage 3: partial union; the epiphysis is attached, but a line is
visible
Stage 4: complete union; the epiphysis is attached and a line is
not visible
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The Medial Clavicle in Stages 1–4
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Age Determination Using Epiphysis
Stage of Union
of Medial Clavicle
Male
Female
21 or younger
20 or younger
Non-union with separate
epiphysis
16–21
17–20
Partial union
17–30
17–33
21 or older
20 or older
Non-union without
separate epiphysis
Complete union
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Gender Differences in Bones
Determination of sex is crucial to the analysis of unidentified
human remains. The pelvis offers the most definitive traits.
Comparison of three characteristics of the os pubis gives the
information used to identify sex.
Male Pelvis
Female Pelvis
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Gender Identification
A. The female (top) has a wider pubic body
than the male (bottom).
B. The female has a wider subpubic
concavity or subpubic angle.
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Gender Identification, continued
C. Most females have a ventral
arc present.
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Male
Female
Subpubic Angle
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Determine which are male and which are female.
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Gender Differences
The rib cage and shoulders of
males are generally wider and
larger than those of females. In
addition, about one person in
20 has an extra rib. This is
more common in males than in
females.
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Skull Gender Differences
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Gender Differences, continued
In males, the index finger is sometimes shorter than the
third finger. In females, the index finger is sometimes
longer than the third finger. This is not often used as an
indicator of gender, as there are many exceptions.
Is this a male or female hand according to
the above rule?
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Race
Race is difficult to determine from most skeletal remains, especially
since pure races are becoming uncommon. An experienced
forensic anthropologist can generally place skulls into one of three
groups:
• Caucasoid—European, Middle Eastern, and Indian descent
• Negroid—African, Aborigine, and Melanesian descent
• Mongoloid—Asian, Native American, and Polynesian descent
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Race Characteristics
Caucasoids—have a long, narrow nasal aperture, a triangular
palate, oval orbits, narrow zygomatic arches, and narrow
mandibles.
Negroids—have a wide nasal aperture, a rectangular palate,
square orbits, and more pronounced zygomatic arches. The
long bones are longer, and have less curvature and greater
density.
Mongoloids—have a more rounded nasal aperture, a
parabolic palate, rounded orbits, wide zygomatic arches,
and more pointed mandibles.
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What differences do you notice among these
three skulls? Can you determine race?
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Facial Restoration
After determining the sex, age,
and race of an individual, facial
features can be built upon a
skull to assist in identification.
Erasers are used to make
tissue depths at various points
on the skull. Clay is used to
build around these markers,
and facial features are molded.
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The Body Farm
The Body Farm is the nickname of a two-and-a-half-acre research facility in
Tennessee developed in 1980 by Bill Bass where bodies are placed in
various conditions and allowed to decompose. Its main purpose is to
observe and understand the processes and timetable of postmortem
decay. Over the years it has helped to improve the ability to determine
“time since death” in murder cases.
Hic locus est ubi mortui viveuntes docent.
“ This is the place where the dead teach the living.”
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Anthropologist at Work
This anthropologist is
hard at work dusting
away material from
these embedded bones.
Picture taken at
Chicago’s Museum
of Natural History
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More Applications
Forensic experts may be called upon
to give information on the life and death
of humans and animals in unique
circumstances, including:
Mass murder (Oklahoma bombing, plane
crashes, World Trade Center)
Earlier man (mummies, Iceman, Lindow
Man)
Historical significance (Holocaust,
uncertain death of famous people)
Prehistoric animals (dinosaurs)
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Animal Facial Restoration
Determining what T. Rex looked like using the bone formation.
From this:
To this:
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Forensic Pathology
Death Detectives
Forensic Pathologist
Forensic Pathologist - investigates
sudden, unnatural, unexplained, or
violent deaths. They usually perform
autopsies to determine cause of death
 4 yr. Degree + Med School + Residency
+ Medical Pathology Training (2 years)
 Work in hospitals or as medical
examiner

Kendall/Hunt Publishing Company
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Pathologist Conclusions
 Five
Conclusions drawn for
investigation:
– Natural
– Homicide
– Suicide
– Accident
– Undetermined
Kendall/Hunt Publishing Company
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Forensic Pathologist
 Way
time of death are determined:
– Algor Mortis - loss of body heat
– Livor Mortis - 0-12 hours, settling of blood
– Rigor Mortis - 24-36 hours, muscles relax
and become rigid
– Potassium levels on ocular fluid
Kendall/Hunt Publishing Company
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Livor Mortis – Lividity
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Rigor Mortis
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Pathologist v Coroner

Coroner is elected official – no
requirements exist, most funeral people
– Historically they solved crimes
– Power to call grand jury
– Being eliminated in other states
– Georgia still has position, county decision
• Fulton does not have a coroner
– Mostly shuffles paperwork, defers to
medical examiner’s
office
Kendall/Hunt Publishing Company
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When notice to coroner/medical
examiners office is required

Death is:
– Violent
– Suicide
– Sudden w/ apparent good health
– Unattended by physician
– Suspicious, especially under 16 yoa
– Under 7 yoa unless expected
– Execution
– Inmate of state facility
Kendall/Hunt Publishing Company
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When notice to coroner/medical
examiners office is required
Once notified they decide if further
investigation is needed
 Autopsy a possibility

– Required in under 7 yoa
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Autopsies
Means - “see for yourself”
 Purpose is to learn the truth about the
person's health during life, and how the
person really died
 2 types: medical & forensic
"Hic locus est ubi mors gaudet succurrere
vitae“
"This is the place where death rejoices to
teach those who live”

Kendall/Hunt Publishing Company
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Autopsies

Religious Issues:
– Orthodox Jews: usually require Rabbi
present, very resistant to autopsies
– Muslims: also resistant
– State has power to ignore religious
concerns
Kendall/Hunt Publishing Company
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Autopsies: Method
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examine the outside of the body
body is opened using a Y-shaped
incision from shoulders to mid-chest
and down to the pubic region
top of the skull is removed, and the
brain is very carefully cut free
breastbone and attached rib cartilages
are removed
chest organs, including the heart and
lungs, are inspected
Kendall/Hunt Publishing Company
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Autopsies: Method
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take blood from the heart to check for
bacteria
blood, urine, bile, or even the fluid of
the eye used for chemical study and to
look for medicine, street drugs,
alcohols, and/or poisons
After any organ is removed, the
pathologist will save a section in
preservative solution
Kendall/Hunt Publishing Company
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Autopsies: Method
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Organs are all weighed
Heart is removed
Neck organs, large airways, and lungs
are removed in one piece
Liver is removed and sliced
Digestive tract removed
then renal/sex organs removed
Any suspect organ is inspected closely
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Autopsies: Method
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Organs returned to cavity or cremated
Body sewn up, baseball stitch
Head more carefully sewn
Body washed and forwarded as
requested by family
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