Transcript FORENSIC ANTHROPOLOGY - Bio-Guru

FORENSIC ANTHROPOLOGY
Anthropology?
• Anthropology is the study
of humans, past and
present.
– Sociocultural Anthropology
– Biological (or Physical)
Anthropology
– Archaeology
– Linguistic Anthropology
Forensic Anthropology?
• Forensic anthropology uses the science of
physical anthropology and human osteology
to assist in solving crimes.
• It is especially useful when the victims’
remains are in the advanced stages of
decomposition.
• A forensic anthropologist can assist in the
identification of deceased individuals whose
remains are decomposed, burned, mutilated
or otherwise unrecognizable.
Employment
CONSULTING: PART-TIME
MEDICAL EXAMINER’S OFFICE: FULL-TIME
FEDERAL GOVERNMENT: DEPARTMENT OF DEFENSE
First questions asked by a FA
• Is it even bone?
– It could be a stone, shell, plastic, or any number of
items that look like bone to the naked eye
• If it is bone, is it human?
– People bury their pets in their backyards
– Wild animals die and deposit bones
• If it is human, what part of the skeleton is it?
• If it is human how did he/she die - is it a crime
scene/cold case?
It is rarely this obvious!
• Anthropologists don’t always find intact
skeletons
• Often times it is just small pieces of bone
How much of this debris is bone?
What part of the skeleton is it?
We can tell human and animal bones apart
by observing:
• Macroscopic differences:
– Compare overall measurements of bones
– Compare measurements of various
Ridges
Projections
Grooves
Openings (Foramina)
• Microscopic differences
– Compare bone tissue under microscope to
determine if osseous tissue is similar
Measurements
Macroscopic Differences in Bones
Greater Trocanter
Head
Lesser Trocanter
Medail and Lateral
epicondyles
(patellar side)
Baboon femur
Human femur
Microscopic differences
Human bone thin section
Dinosaur bone thin section
Osteology
• The study of Human bones and skeletons
Osteology uses X-rays
Normal foot
Foot in high heels
Normal hands
Arthritic hands
Osteology also includes Odontology
Dead men tell tales
• A skeleton or a badly decomposed body can
still reveal a lot:
– Sex of decedent
– Approximate age of decedent
– Ancestry of decedent
– Stature of decedent
– Trauma to decedent’s body
– General health/condition of decedent (pathology)
Determining Sex of Decedent
Sex of Decedent
• The pelvic girdle is very important in
determining sex of decedent
• If the pelvis is not found, the skull can reveal a
lot of gender information
Sex of Decedent based on Pelvis
Female
(Fibrocartilage)
Male
More Pelvis Comparisons
Sex of Decedent based on Skull
• Males have brow ridges in the frontal bone, whereas
females have smoother frontal bones without ridges
• Males have squarer chins and females pointier ones
• Males have a more acute jaw angle and females have
a wider, more obtuse jaw angle
• Males have a more prominent mastoid process than
females
• They also have a more pronounced ridges in the
occipital bone for neck muscle attachment than
females
Male
Female
Determining Age At Death
Adult vs. Infant skulls
• Infant skull plates have not merged and
formed sutures – they still have soft tissue
called fontanels
• Adults have sutures
Infant skull vs. Adult skull
Adult teeth vs. young teeth
How old is this person?
Epiphyses
An epiphysis is a region
of bone growth found at
the ends of bone shafts.
These regions are not
fused to the rest of the
bone shaft during the
ages of growth.
Once growth has
ceased, they fuse with
the shaft. Usually after
the age of 17.
Fused = adult
Epiphysis
The arrows point to gaps between the
long bone and the epiphyseal plate.
Unfused epiphyseal plate = juvenile
(under age 17)
Fused Epiphysis
Older
Even Older – No gaps visible
Determining Ancestry
Ancestry of Decedent
• The three original races are: Caucasoid, Negroid
and Mongoloid
• However, today human races are no longer pure
• So ancestry is quite difficult to determine from
skeletal remains – but the skull can shed some
light on the matter
Facial Bones of Importance in Determining
Ancestry
What to Compare:
1. Inter-orbital space
2. Nasal aperture
3. Teeth
4. Mandible
Mongoloid/Asian Skull
Negroid/African Skull
Caucasian/European Skull
Aboriginal/Australian Skull
Determining Stature
Stature Estimation
1. Measure long bone(s) if available
2. Plug values into a formula
3. Range established for stature of decedent
e.g. 5’ 2” – 5’ 5”
Determining Cause of Death
Cause of Death
• The cause of death is often determined by
observing injuries to the skeletal remains.
• The injury could be:
– Antemortem – before death
– Perimortem – During death (could be the cause of
death)
– Postmortem – After death
Perimortem Injuries
Iron age period male with perimortem sword wound to the skull.
Injury occurred at or around the time of death
and may have even caused the death
Antemortem Injuries
Injuries that occurred during
the decedent's lifetime – they
often appear healed.
More Antemortem Injuries
Postmortem Changes
Identifying the Decedent
Identification of Body in Good Condition
• If a body is not badly
decomposed or damaged,
visual
confirmation/identification
can be made by one or
two people.
• Comparison of driver's
license, passport, or other
authoritative photo ID
should also be made
before confirming personal
identification.
• Reliable identification becomes
increasingly difficult as time
passes, due to decomposition
Identification of Skeletal Remains
• When skeletal remains are found, and the victim
remains unidentified after traditional means of
identification fail, investigators may call upon the
forensic artist to utilize a technique called 3-D facial
reconstruction.
• This technique can be done manually or with
computers by facial reconstruction professionals
Determine Tissue Depth
• Proper tissue depth
data is determined
by race, gender,
and age.
• Depth pegs are
applied to specific
spots on the skull
Place Clay Strips of Appropriate Thickness
• The different clay
strips will simulate
appropriate muscle,
connective tissue and
skin thickness
• Glass eyes are placed
in sockets based on
racial information
Final touches
• The clay is smoothed
and painted according
to racial information
• A wig is used based on
racial and gender
information
The Final Product
• Authorities release the final images to the
public for identification
Using Computers
for Reconstruction
• Race, gender, and
other information
about the skull can be
plugged into formulae
and a computer
application generates
an image.
The Death of Tut Ankh Amen
Case Study 1
POMPEII
Case Study 2
Rediscovering Pompeiani
• Giuseppe Fiorelli took charge of the excavations in 1860.
During early excavations of the site, occasional voids in the
ash layer had been found that contained human remains.
• It was Fiorelli who realized these were spaces left by the
decomposed bodies and so devised the technique of injecting
plaster into them to perfectly recreate the forms of Vesuvius's
victims.
• What resulted were highly accurate and eerie forms of the
doomed Pompeiani who failed to escape, in their last moment
of life, with the expression of terror often quite clearly visible.
• This technique is still in use today, with resin now used
instead of plaster because it is more durable.