Forensic Anthropology

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Transcript Forensic Anthropology

PHYSICAL ANTHROPOLOGY
Forensic Anthropology
The Study of Human Remains
Forensic anthropology is the study of
human remains.
• The primary goal of a forensic anthropologist is to
determine the biological identity of an individual
(i.e. sex, age-at-death, stature, and population
affiliation).
• A forensic anthropologist may also be called upon
to try and figure out what happened to an
individual by examining his or her bones for
evidence of trauma.
• They may also assist investigators in making a
positive identification of an individual from his or
her skeletal remains.
Kyra Stull - Forensic Anthropologist
• http://vimeo.com/29104189
• This is a short piece about Kyra Stull. Kyra is
forensic anthropologist and runs the Forensic
Anthropology Center at Texas State. She
oversees a body farm.
Sex Determination:
• In general, males have bigger bones and larger areas of
muscle attachment than females
• The pelvic bones are the best indicators of sex
• The skull, or cranium, is the second best indicator of
sex
• Long bones may also be used for sex determination,
although they are less accurate than the skull or pelvic
bones
• As significant skeletal indicators of sex do not develop
until puberty, it is very difficult to accurately determine
the sex of children and young adolescents
Age Estimation:
• A number of methods are used to estimate the age-atdeath of an individual from his or her skeletal remains
• The most common methods used to estimate the age of
sub-adults (individuals under the age of 18) are bone
formation and growth and dental formation and eruption
• Among the most common methods used to estimate the
age of adults are cranial stature closure, changes to pelvic
bones, and tooth wear
• It is easier to estimate the age-at-death of sub-adults
because growth occurs in a known pattern
• Age estimation is not an exact science – age estimates are
usually expressed in a range of years
– eg. this individual was 40-50 years of age at the time of his
death
Stature Estimation:
• Stature or height is estimated by measuring
the maximum length, in centimeters, of one or
more of the six major long bones and plugging
the number into a formula
• Separate formulae have been developed for
different populations so it is important to
know the population affiliation of the
individual before doing the calculation
Population Affiliation:
• Physical anthropologists generally agree that
there is no such thing as race (i.e. it has no
biological basis); however forensic
anthropologists are often called upon to
determine the racial or population affiliation (also
referred to as “ancestry”) of an individual from
his or her skeletal remains
• This can be very difficult to do
• Determination of population affiliation from
skeletal remains is usually done using the skull,
and is based on the fact that different
populations have different facial features
Positive Identification:
• A number of different methods are used to make
a positive identification from skeletal remains
• The most common method is dental records
• Other methods include medical records, DNA,
frontal sinus patterns, and photographic
superimposition
• Facial reconstruction may be used to gather
further clues in a case, but it is not used to make
a positive identification
Articles giving more information about
forensic anthropology and its
methods:
• http://www.pbs.org/opb/historydetectives/te
chnique/forensic-anthropology/
Learning from Skeletons
• Label the diagram
of the skeleton
from the following
information
• You must
summarize the
content
Teeth
Skull
• Study the teeth. If they're
• Look for the sagittal
worn down it could be a
suture – the squiggly
sign of a poor diet. If they're
line that runs the
well-maintained and/or
have good dental work such
length of the skull –
as fillings, they were able to
and note whether is it's
afford proper dental care—
completely fused. If it
another clue as to the
is, the remains are
identity of your skeleton.
likely to be of someone
Consult a scientist who
specializes in teeth, known
older than 35. Look for
as an odontologist. They can
a second line at the
determine how old a person
front of the skull -- the
was at death, what kind of
coronal suture – which
health they were in and
fully fuses by age 40.
what kind of diet they had
DNA
• DNA samples may be
taken from any
existing hair tissue. As
well as positively
identifying someone, it
may be useful in
identifying a person's
rethnicity or tribal origins
Sternum
• Examine where the ribs
join the sternum. This is
also a good indicator of
age. A forensic
anthropologist will
compare it against a
database of standard
markers and it is often
more accurate as it is not
a weight-bearing bone
and remains unaffected
by childbirth.
Pelvis
• Look for the pubic symphysis, which is the joint located
in the pelvis. The older the person at death, the more
pitted and craggy these bones will be. Forensic
anthropologists will compare this against a database of
standard markers to learn the age of the
skeleton. Check if there are any soft marks on the
cartilage which are left by childbirth as the bones soften
to allow easier birth.
• To identify gender, assess the pelvis shape; men have a
narrow, deep pelvis and women a wider, shallower
pelvis, better-suited to carrying a baby. For a quick
identification in the field, a forensic anthropologist will
find the notch in the fan-shaped bone of the pelvis and
stick their thumb into it. If there's room to wiggle the
thumb, then it's a female; if it's a tight fit, it's the
skeleton of a man
Wrist
• Examine the wrists, as
bones often hold clues to
the primary work of the
decedent. Bony ridges
form where the muscles
were attached and pulled
over the years. A forensic
anthropologist might find
a bony ridge on the wrist
and decide the dead
person may have been
someone who used their
hands for a living, such as
a chef or seamstress
Bugs
• When the skeleton is first
discovered, take samples
from around the remains
including any bugs you
come across. Insects such
as blowflies have a very
distinct lifecycle and often
plant their eggs on newly
deceased bodies. By
identifying the stage of
the lifecycle, a near-exact
time of death can be
established. This science
is known as forensic
entomology
Interview with a Forensic
Anthropologist
• Forensic anthropologist and Smithsonian
scientist Doug Owsley has been involved in
cases ranging from Waco, Texas to Croatia.
Recently, Owsley spoke with FRONTIERS about
his work, his curiosity, and his love of learning.
• http://www.pbs.org/saf/1203/features/owsle
y.htm
Paleoartist – Viktor Deak
Skull Reconstruction
• (click launch interactive)
• http://www.pbs.org/wgbh/nova/evolution/bu
ilding-fossils-faces.html
Read the Article Real Face of Jesus
• http://www.popularmechanics.com/science/h
ealth/forensics/1282186
Real Face of Jesus
• History Channel Documentary - The Real Face
of Jesus from the Turin Shroud
• http://abcnews.go.com/GMA/video/facejesus-revealed-10248139
• http://www.youtube.com/watch?v=OqBQSFP
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