Unit 9: Forensic Anthropology
Name three reasons why it is extremely difficult to determine the true race of a skeleton...
1. anthropologists use a three race model, which are caucasian (European), asian (amerindian), and african 2. although there are some common characteristics among these groups, not all individuals have skeletal traits consistent with geographical origin 3. people of mixed racial ancestry are common
Name four examples of long bones that can be useful in determining the height of an individual
1. femur 2. tibia 3. humerus 4. radius
Name the five ways to distinguish race summary
1. shape of eye sockets 2. absence or presence of a nasal spine 3. measurements of the nasal index 4. width of the face 5. angulation of the jaw and face
The most accurate estimations are made from...
1. teeth 2. epiphyses or growth plates 3. pubic symphysis 4. cranial structures (three major cranial structures appear as distinct lines in youth and gradually close from the inside out)
Describe the female pelvis
1. wider sub pubic angle 2. broad, shovel-like ilium 3. flexible pubis symphysis
About how many bones that are claimed to be human are actually other animals?
15%
About 1 in how many people have an extra rib?
20
How many bones are in the body as an adult?
206 bones
Epiphyseal fusion varies with sex and is typically complete by age...
25
Osteoporosis
A deficiency of calcium in the bones; common for women over the age of 30 (menopause and childbearing are also factors of a decline in bone strength)
How can you find buried remains?
Aerial and canine searches; canine helpful when aerial searches cannot be done due to high grasses
Hormones
Affects the amount of calcium in the blood and bones
Use one important word to describe bones
Alive! (perform cellular respiration)
Forensic Anthropology
Analysis of human remains applied to legal matters and investigation
Race
Analyze skull for common characteristics of the "four races" (the four races that the field of forensics had identified much earlier)
Epiphysis line
Appears where cartilage is replaced by bone; when cartilage is fully replaced, the line is no longer visible *this information can be used to approximate a skeleton's age
Bones fuse...
At set ages
Ligaments
Bands that connect two or more bones together
Nasal spine
Base of the nasal cavity, on either side of the nasal spine; sharp ridges (nasal silling), rounded ridges, or not ridges at all (nasal guttering)
Life cycle of bone
Bone is deposited, breaks down, and then is replaced
Osteobiography
Bones contains a record of the physical life
Under 30 years of age...
Bones increase in size
Adults and seniors are aged...
By amount of wear on particular areas of bone
Nasal index (traits)
Caucasian: <0.48 Asian: 0.48-0.53 African: >0.53
Nasal spine (traits)
Caucasian: prominent spine Asian: somewhat prominent spine African: very small spine
Shape of orbital openings
Caucasian: rounded, somewhat square Asian: rounded, somewhat circular African: rectangular or square
Nasal silling/guttering (traits)
Caucasian: sharp ridge (silling) Asian: rounded ridge African: no ridge (guttering)
Prognathism (traits)
Caucasian: straight Asian: variable African: prognathic
Physical anthropology
Comparing differences among human beings and cultures
Tendons
Connect muscle to bone
Age 40+
Cranial structure closure, periodontal disease, arthritis, occupational stress, other clues suggesting wear
Marrow
Creates blood cells
Sex
Determined by examining the skull, pelvis, humerus, and femur
Age and statue (height/build)
Development of teeth, bone growth, cranial structure lines, length of specific bones (i.e. femur)
Age 6-25
Epiphyseal fusion (fusion of bone ends to bone shaft)
Prognathism
Extended lower jaw
Chemical analysis
Extract DNA, nutrient tests, etc.
Non-union with separate epiphysis
Female: 17-20 Male: 16-21
Partial union
Female: 17-33 Male: 17-30
Complete union
Female: 20 or older Male: 21 or older
Non-union without separate epiphysis
Female: 20 or younger Male: 21 or younger
Occipital protuberance
Female: absent Male: present
Frontal bone
Female: higher and more rounded Male: low and sloping
Shape of eye
Female: more rounded Male: more square
Mandible shape from underside
Female: more v-shapes Male: more square
Zygomatic process
Female: not expressed beyond external auditory meatus Male: expressed beyond external auditory meatus
Shape of eye orbit
Female: rounded Male: square
Mandible shape
Female: rounded, v-shaped Male: square, u-shaped
Upper edge of eye orbit
Female: sharp Male: blunt
Ramus of mandible
Female: slanting Male: straight
Nuchal crest
Female: smooth Male: rough and bumpy
Surface of the skull
Female: smooth Male: rough and bumpy
Upper brow ridge
Female: thin and smaller Male: thick and larger
Teeth...
Form and erupt at certain ages
Epiphyses
Found at the ends of the bones; their function is to allow for growth *good places to look for changes in estimating age; there are similarities that allow for generalization in estimating age
How can the estimate of an individuals height be made?
From their long bones *gender and race are also taken into consideration
The rib cage and shoulder in males are...
Generally wider and larger than those of females
What is the sub pubic angle of a female?
Greater than 90 degrees
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
Caucasoids
Have long, narrow nasal aperture, a triangular palate, oval orbits, narrow zygomatic arches, and narrow mandibles
Forensic anthropology
Identifying characteristics of the remains of individuals in questions of civil or criminal law
Explain of an example of bones revealing a clue that points to a certain individual
In a right handed person, right arm bones might be slightly larger than the bones of the left arm; x-rays might identify prior fractures, pins, and artificial joints
There are larger gaps which close slowly over time in...
Infants
What is the sub pubic angle of a male?
Less than 90 degrees
Is having an extra rib more common in males or females?
Males
Trotter Method
Mathematical regression formula based on the Terry collection and hundreds of servicemen from WWII and the Korean War
Osteometry
Measurement of human bones
Histology
Micro-structure of bone and teeth
MNI
Minimum number of individuals
Crests and ridges are...
More pronounced in males
What is the forehead shape of a male?
More sloped
What can bones be easily mistaken for?
Other materials, such as plastic
How many bones are there in the body at birth?
Over 450 bones
Forensic anthropologists frequently work with...
Pathologists, odontologists, and homicide investigators
What bone offers the most definitive traits of the sex of an individual?
Pelvis; the surface of a woman's pelvis can be scarred
Over 30...
Process reverses
Shape of eye orbits
Round or squareish
What do forensic anthropologists do?
Search the crime scene, excavation and recovery, questions of identification, time since death, and identify the cause, manner, and mode (mechanism) of death
Osteoclasts
Second type of bone cell; specialized to dissolve bones (reshape as they grow, balance calcium levels, remove cellular waster and debris from bones)
Diaphysis
Shaft of long bones that make up most of the bone's length
Exercise...
Slows deterioration
Chins are more...
Square in males
Collagen
Structural protein found in the skin and connective tissue; also important for flexibility
Anthropology
Study of all aspects of human development and interaction
Age 0-5
Teeth are the best; dental eruption patterns are very predictable
Nasal index
The ratio of the width to the height of the nose, multiplied by 100
Forensic anthropologists analyze skeletal remains to determine...
The remains of a victim; cause of death, identity, etc.
By about age 30...
The structure at the back of the skull closes
By about age 32...
The structure running across the top of the skull, back to front, closes
By about age 50...
The structure running side to side over the top of the skull, near the front, closes
How is age determined?
Through the observation of changes in the morphology of bone that occur as a normal part of the aging process
Age 25-40
Very hard to determine exact age
Anthroposcopy
Visual inspection of the human body
When are the lines very clear on bones?
When a person is not out of puberty
Ossification
When osteoblast cells migrate to the center of cartilage production and deposit materials
Osteoblast cells
Where bones originate
The jaw is...
Wider and robust in males than in females
Cartilage
Wraps the ends of bones for protection and prevents scraping
When is age determination most accurate?
Younger than 26 years old