Transcript Forensic Anthropologist ppt /Beginning

Forensic Anthropology
The 206 bones of the human skeleton
can also tell a story.
video
 Specialists called forensic anthropologists are trained
to analyze the secrets locked in a bone’s shape and
structure and can use this information to help solve
crimes, trace human origins, or identify those who
have gone missing
Introduction
The main bones we’re interested in:
*Cranium/Skull
*Pelvis
*Tibia
*Femur
*Humerus
The specific structure of your bones
reveals information about your
gender
 height
 age
ethnicity.
What Can We Learn?
 Determination of Sex:
-Pelvis
-Skull
 Determination of Race:
-Skull
 Approximate Age:
-Growth of long bones
 Approximate Stature:
-Length of long bones
Determination of Sex
 The Pelvis is the best area to study sex
-Females have wider sub pubic angles for giving birth
 In general, males have larger and bigger muscles, therefore those
areas of the bones where muscles attach tend to be larger and
rougher than the same areas on female bones. With this in mind,
take a close look at each skull, especially, the browridge (the ridge
above the eye socket ), mastoid process (part of a temporal bone
that extends down behind the ear), and external occipital
protuberance which covers the back lower part of the head (it may
protrude like a hook in the male, called an inion hook).You may
have observed the similar size of the occipital protuberance in
these two skulls. Analyzing human skeletal remains often aren't cut
and dry.
 Anthropologists need to examine numerous characteristics by
making visual comparisons and taking measurements before
forming their conclusions
Determination of Sex
 The Cranium/Skull is also very helpful in determining sex
- Men’s chins are significantly more square and their ridges
and crests are more pronounced
Determination of Race
Forensic Anthropologists place bones in three races:
Caucasoid (includes European, Middle Eastern, and East Indian
descent),
Negroid (African, Aborigine, and Melanesian), and
Mongoloids (Asian, Native American, and Polynesian).
 It’s very difficult to determine race because many people are
biracial and also not all individuals have skeletal traits that are
consistent with their race
 The nasal index (the ratio of the width to the height of the nose
multiplied by 100), nasal spine, prognathism (extended lower
jaw), and the shape of the eye orbits all help determine race
Determination of Race
 Caucasian
-Nasal index: <.48
-Nasal Spine: Prominent
-Prognathism: Straight
-Eye orbitals: Rounded, somewhat square
• Caucasoids: have long narrow nasal aperture, triangular
palate, oval orbitz, narrow zygomatic arches, and narrow
mandibles.
Determination of Race
 Asian:
-Nasal index: .48-.53
-Nasal Spine: somewhat prominent
-Prornathism: Variable
-Eye orbitals: Rounded, somewhat circular
• Mongoloids: have a more rounded nasal aperture, a parabolic
palate, rounded orbits, wide zygomatic arches, and more
pointed mandibles.
Determination of Race
 African:
-Nasal index:>.53
-Nasal Spine: Very small spine
-Prognathism:Prognathic
-Eye orbitals: Rectangular or square
• Negroids: have a wide nasal aperture, a rectangular palate,
square orbits, and more pronounced zygomatic arches. The
long bones are also longer and have less curvature and
greater density.
Over time there has been a
greater amount of interracial
mixing making the
distinctions between features
for race more difficult to
characterize.
Determination of Age
 We use teeth, bone fusion, the hardness, wear and tear, and
any damages to determine age
Determination of Age
 0-5: teeth are best
 6-25: fusion starts and ends at about 25
 25-40 bones are very hard
 40+: wear and tear on bones
Determination
of Age
Determination of Stature
 Our long bone length
(femur, tibia, humerus)
is proportional to height
 Formula for height:
2.89(humerus length)+78.10 (all in cm)
 Example: If the humerus length=30.8,
their height would be determined
by 2.89(30.8)+78.10 cm
BUT!!!
 Males and females have slightly
different body proportions, with
females having relatively longer
legs and males having relatively
longer arms.
 Therefore, we use different
mathematical formulas to
estimate height.
Miscellaneous Information
 We can find out how they died based on any trauma
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(gunshots to head, etc.)
Any evidence of post mortem trauma such as bite-marks
(cannibalism or chewed on by animals)
Any activities the victim enjoyed, example:You can find out
different activities the victim liked based on their damage and
“wear and tear” and size in certain areas of their body
ex- swimmers versus runners
tennis players racket arm…
 Last week, a young couple was out for an early morning run.
 Stopping to catch a drink, they stumbled upon what appeared
to be a human skull. More bones were later located at the
scene and are available for your examination.
 In this project, you will assume the role
of a forensic anthropologist and
complete a detailed examination of
skeletal remains.
 Forensic anthropologists use a
combination of quantitative and
qualitative measures to predict traits
from bone
Proficient Example
 On February 23, 2015, some joggers discovered skeletal remains in
Parktown Park. With a backlog of missing persons, it was crucial to come
up with a preliminary identification of the bones.
 Our forensic anthropology team believes that the recovered bones are
from a 25 year old, Asian female, between 5’3’’ and 5’5’’. Cause of
death is not known at this time. Based on the 95 degree angle of the …..,
and ….., we are fairly confident in saying that the deceased is a female.
Due to the fact that the …… measured in the range of …., and the ….
was….., the races was determined to be …… INCLUDE SEX, AGE,
RACE AND HEIGHT JUSTIFICATIONS…
 Recommendations for further analysis include …. And ….. In similar past
cases, definite identity was made through…. and the families were able to
receive closure.
 In conclusion, we recommend that … tests be run on all missing persons
meeting the description of a …………