FORENSIC ANTHROPOLOGY

“The pathologist’s domain is that of dead bodies; the forensic anthropologist applies

his expertise to skeletal remains.”

I – Recovery of Remains II – Skeletal examination III – Forensic identification IV – Reconstructing identity

Recovery of Remains

Legal aspects

Court order for exhumation

Exact location of burial

Date and time of exhumation

Complete list of persons attending

Scaled sketches of gravesite

Photographs Burial site Coffin in situ Coffin above ground

Clandestinely buried bodies

Helicopters Disturbances of soil

or vegetation Aerial photography

with infrared film

Ground search Sunken area Damage to vegetation Steel rod probe Methane gas detector Grid pattern Remove only a few

inches of soil at a time

After remains are recovered

Coffin or remains transported to morgue or other facility

Careful opening – protect evidence for court

Anthropology Research Facility Decay rate facility Mummification –

desiccation Adipocere – “grave

wax” Freezing Moisture

Even is not in any type of container, bodies will last longer underground

Rule of Thumb for rate of decomp – One week open air =

two weeks in water = eight weeks underground

“The Body Farm”

Skeletal examination

“A person’s job, diet, illness, chronic disease and/or trauma leave their mark on a person’s skeletal remains.”

Identification techniques

Morphological analysis Features Marked by size and

shape

Metric analysis Hamann-Todd/

Cleveland (3,100) Terry/Smithsonian

(1,600) Cobb/

Howard University (600)

Formulas from Metric Analysis

From collections

Forensic Data Bank (FDB) – UT Knoxville in 1980s

FORDISC – UT in 1993 and updated periodically – computer program

Anthropological Examination

Excavated remains cleaned in forensic lab

Arranged in correct anatomical order

Depending upon bones present, forensic anthropologist may be able to determineSexRaceAgeStature

Immature vs Mature Skeleton

Before puberty biological identification of remains can be difficultBones are mostly cartilageGrowth plates not fusedSexual differences not as pronouncedBest determinant – skull with dentition

Sex determination - PelvisTrait Male Female

Subpubic angle < 90 o > 90 o

Pelvic aperture Narrow/heart-shaped

Wide/round

Greater sciatic notch

~ 30 o > 60 o

Acetabulum Large/deep Small/shallow

Scars of parturition

No If given birth

Sex determination – Long Bones

Head diameter Male Female

Humerus 45 mm or greater

43 mm or less

Radius 24 mm or greater

21 mm or less

Femur (vertical diameter)

45 mm or greater

43 mm or less

Humerus, Radius, Femur

Sex determination - SkullTrait Male Female

Frontal bone Steeper/more rugged

Rounder/smoother

Supraorbital ridges

Larger/more prominent

Not as prominent

Zygomatic arches

Extend past External

auditory Meatus

Do not extend past EAM

Orbits Thicker/more blunt

Sharper/rounder

Race determination - Skull

Race determinations Mongoloid

Asian Native American Indian

Caucasoid White Hispanic

Negroid African American

Characteristic1 – Nasal Aperature2 – Malars 3 – Orbits 4 – Prognathism 5 – Mandible 6 – Incisors

Mongoloid

1 Rounded

2 Wide/Project

3 Squared

4 Moderate

5 Robust

6 Shovel-shaped

Caucasoid

1 Narrow/Elongated

2 Recede

3 Sloped/Rhomboid

4 Reduced

5 Medium

6 Blade-shaped

Negroid

1 Flared

2 Recede/Reduced

3 Rounded

4 Extreme

5 Gracile

6 Blade-shaped

Age determination - Dentition

Characteristics of Dentition Less affected by

environmental factors Hardest structure in

human body Tooth buds developing

2nd month after conception

Eruption follows pattern

In Adult skeleton Resorption of bone Attrition Root resorption Cementum annulation

– counting tree trunk rings

Deciduous eruption

Deciduous teeth Average Age of Eruption

Central incisors 6 – 8 months

Lateral incisors 8 – 10 months

First molars 12 – 16 months

Canines 16 – 20 months

Second molars 20 – 30 months

Permanent eruption

Permanent teeth Average Age of EruptionFirst molars 6 – 7 years

Central incisors 6 – 8 yearsLateral incisors 7 – 9 years

Canines 9 – 12 years1st and 2nd premolars 10 – 12 years

Second molars 11 – 13 yearsThird molars 17 – 21 years

Age – Long bone development

Age – Skull development 29 bones in the skull

Initial fusion few weeks postnatal

Continues through age 21 – 35 yrs

Mathematical formulas for using sutures to determine age

Height determination – Long bones

Rule of thumb – “Height roughly equals 5 times the length of the humerus.”

Since it is only an estimate, always have height be a range

Formulas 2.38 (femur length cm)+61.41 = Stature +/- 3.27

Evidence of Trauma

Manner of death Accident Suicide Homicide Natural causes Undetermined causes

Cause of death – medical reason for death Asphyxia Drowning Stabbing Gun shot wound Etc

Determine when Trauma took place

Antemortem – before death

Perimortem – around the time of death

Postmortem – after death occurred

Antemortem trauma

Bone healing or bone remodeling – depends upon Age/health of individualNature/extent of injuryLocation of injury

Bone healing has a distinctive lookBony callusSmooth edges

Usually no clues as to death

Perimortem trauma

Lesions have no sign of healing

Postmortem trauma

Intentional dismemberment Tool marks left on

bone

Unintentional dismemberment Animal tooth marks left

on bone

Burned bone

Short duration fires Skeleton usually

survives Cremation

Very small fragments and ash

Differences in prolonged fires with green bones and dry bones

Differences

Green bone – fleshed bones Deep transverse

fracture lines Warping Blackened tissue

Dry bone Longitudinal fracture

line Superficial cracking Little warping

Reconstructing Identity

Forensic Odontology Facial Reconstruction Nuclear or Genomic DNA Mitochondrial DNA

Forensic Odontology

Antemortem and Postmortem dental charting and radiographsMissing,unerupted, or extracted teeth;

supernumerary teethRestorations and prosthesesDecay

Facial Reconstruction

Plastic 3 D reconstruction

2 dimensional reconstruction

Computerized programs for Facial Reconstruction