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Human Remains
chapter 14
eocs (not 16, 17)
objectives
You will understand:
how anthropologists can use
bones to determine:
whether remains are human
gender
age
sometimes race
estimated height
when or how death occurred
You will be able to:
distinguish between a male
and a female skeleton.
give an age range after
examining unknown remains.
describe differences in skull
features among the three
major racial categories.
estimate height by
measuring long bones.
sometimes no body, just bones
forensic anthropologists are
needed now
forensic anthropology
a type of applied anthropology that
specializes in the changes and
variations in the human skeleton
for the purpose of legal inquiry
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
first, a quick look at bones...
osteology is the study of bones
we are born with 350 bones
many fuse, and we end up with 206
bones in an adult human
they are living, breathing parts of our
body
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
Activity 14.1 Identifying Bones
on the handout we will fill in the major bones - those you will know.
skull & mandible
clavicle & sternum & ribs
vertebrae (no need to know colored regions)
all three!
big picture of them all
creepy real ones!
free trivia: the elbow is the ulna
low priority
know ‘em all! (including bluish area, the pubic symphysis)
know ‘em!
low priority
THE HUMAN SKELETON
Skull
Maxilla
Zygomatic process
Mandible
Scapula
Rib
Sternum
Clavicle
Humerus
Xyphoid process
Vertebra
Pelvis
Sacrum
Coccyx
Trochanter
Ulna
Radius
The ones you should know.
Carpals
Metacarpals
Femoral Head
Femur
Patella
Fibula
Tibia
Tarsals
Metatarsals
12
IT
Phalanges
back to forensic anthropology...
questions that need answering from the remains:
are the bones human?
what are the victim's biological characteristics?
how long has the person been dead?
what was the cause or manner of death?
started in 1939 with Dr W. M.
Krogman's classic article on
examination of human remains in
FBI Law Enforcement Bulletin
now we have American Board of
Forensic Anthropology
skeletal remains might be an intact skeleton, a partial
skeleton, a handful of bones, a single bone
may be scattered, buried, or found within a structure
humans vs animals
complete skeleton? easy to see!
but b/c of all kinds of factors that spread the bones out, don't often get
a complete set
many of our bones are at least somewhat similar to animal bones
bones of infants or young children are even tougher; why?
because their bones are small and like animals, and skull and other
bones are not fused and comes apart all over the place
but a real expert can tell
human have rounded cells in cross
section, animals oval or squared off
(most of the time, not always)
animals more brick like and stronger,
human more “round"
biological characteristics
now… how to identify
age, stature, sex, and race are all
crucial
e.g. determine sex and you've
eliminated half the possibilities
what if you could narrow it to thirtysomething, six-foot Caucasian male?
and spotting disease in the bones can
narrow it even further
a complete skeleton can give
correct sex ID 100% of the time,
age to within 5-10 years,
height to within 1.5 inches,
and race much of the time
age
look at teeth,
skull, maturity of
bone growth
centers as well as
normal agerelated changes
in bones and
joints
young victims can
be narrowed a lot
better because
there is so much
change going on
teeth
we start off with 20 "baby" teeth (deciduous)
and 32 permanent teeth
the loss pattern of baby teeth and the
appearance of permanent teeth are well
established
all permanent are there by age 12; wisdom
teeth “erupt” by age 18
skull
adult? not too useful for
pinpointing age
infants? slightly easier since the
"suture lines" aren't fused
suture lines of adult are fused
long bones are next
three parts to these...
diaphysis (shaft) and two epiphyses
the growth plates are between the diaphysis and the epiphysis
when it is open = growth
when sealed shut = no growth
bone growth is complete by mid-twenties
here growth plate of a 12-year-old
skeleton small with no
fusion of epiphyses?
child
skeleton bigger and
plates partially fused?
teens to early twenties
skeleton bigger and
completely fused?
over 25-ish
complete closure happens at
different times for different bones
bones at elbow fuse about 12-14
hips and ankle around 15
shoulder? 18-20
bottom line here: an
anthropologist can estimate age
by seeing which bones have
fused
pubic symphysis
right and left pelvic
bones join behind at the
sacroiliac joints
but in front at the pubic
symphysis
the cartilage there is
slightly scalloped when
young, straightens as
ages
sternal end of ribs another
indicator
early on end of ribs are smooth
and rounded
as one ages they become pitted
and sharper
age also leads to loss of bone
density and things like arthritis
hip or knee
replacements can help
narrow it down, too
stature
can't just measure tip-to-toe if only
a couple bones; then what to do?
moreover! stature is more than just
height
a 6-foot skinny guy has different
bones than a 6-foot big guy
allometry (the study of growth) allows us to estimate height with just a
long bone or two
most accurate bones to use? the femur or tibia, but can use humerus
Activity 14.2
This isn’t a regular lab. It’s an “activity.”
But use graph paper and give it a Title and Purpose and
Procedure.
Write down each numbered statement & question,
underline it, and leave plenty of room for an answer.
No conclusions or anything else.
Ready?
• Work in your groups of two or three.
• No 3 - Find you height in cm, work
backwards
• No 4 - SKIP
• No 5 - Use humerus and femur
• No 7 - The skeleton in 5’ 2”
yes, there are even
tables to estimate
height with just parts
of bones
guessing the body type is
more of a guessing game
if bones are thick
especially where muscles
join, probably a muscular
person
and if the thicker, stronger
bones are in the left arm
or leg, then probably
favored left side
sex
calling the sex of the young is
tough, since gender-specific
changes don't occur till puberty
and can't always say that males
have the bigger bones...
a woman who does manual labor
has thicker bones than a man who
is some weasel English professor
at some snobby university who has
never done a day of manual labor
in his sad pathetic life
most reliable bone?
pelvis
male pelvis is designed only for support or movement
female pelvis is designed also for childbirth
female pelvis is wider and the pelvic outlet has a
greater diameter for childbirth
male
female
moreover the backside of pubic bone in a woman who has delivered
may be scarred or irregular due to tearing and regrowth of ligaments
skull
tend to be thicker in males (no comments! ;)
but wait! there’s more!
male
female
race
really tough here, especially with all
the racial admixture
Caucasoid—European, Middle
Eastern, and Indian descent
Negroid—African, Aborigine,
and Melanesian descent
Mongoloid—Asian, Native
American, and Polynesian
descent
Caucasoids—have a long, narrow nasal
aperture, a triangular palate, oval orbits,
narrow zygomatic arches, and narrow
mandibles.
Mongoloids—have a more rounded nasal
aperture, a parabolic palate, rounded orbits,
wide zygomatic arches, and more pointed
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.
facial reconstruction
sometimes putting a face on it can help - a lot
know gender, age, and race? then artists can
reconstruct
decades of data can be used to estimate flesh
thicknesses at different points...
erasers are used to
make tissue depths at
various points on the
skull.
clay is used to build
around these markers
facial features are
molded
extra features like hair
and skin color are
added, sometimes
digitally and ...
which can then be used by law enforcement
(odontology)
the identity of an individual can be determined by comparing a person’s
teeth to his or her dental records.
unusual features include:
the number and types of teeth and fillings
the spacing of the teeth
special dental work (bridges, false teeth, root canals)
teeth are often used for body identification because:
they are the hardest substances in the body (they do not
readily decompose).
they are unique to the individual.
X-rays are a good record of a person’s teeth, giving them
a unique identity.
cause of death and anomalies
pathologists often ask forensic anthropologists for help
can ID bullet wounds, knife wounds, predator marks, tool marks, etc.
and can obviously recognize bone replacements, false teeth, etc.
About the only thing left of Hitler’s body
what’s this?
gunshot wound through the leg
remember this from last chapter? what do the ribs show?
eocs (not 16, 17)
Activity 14.2
This isn’t a regular lab. It’s an “activity.”
But use graph paper and give it a Title and Purpose and
Procedure.
Write down each numbered statement & question,
underline it, and leave plenty of room for an answer.
No conclusions or anything else.
Ready?
• Work in your groups of two or three.
• No 3 - Find you height in cm, work
backwards
• No 4 - SKIP
• No 5 - Use humerus and femur
• No 7 - The skeleton in 5’ 2”