Anthropology

Largest bone in the body

Femur

Smallest bone in the body?

Ossicles (ear)

Forensic Anthropology

Identifies skeletal remains where bones are the only evidence

Organizing Collected Bones

Lay out the bones in anatomical position; palms out, thumb to the outside

• Always to the patient’s left and right

Teeth

Analyzed by odontologist-specialized trained dentists

• Teeth made of dentin, enamel (hardest substance in the human body), & cementum

• FORENSICALLY IMPORTANT because they last longer than bones

• Best to determine age of children; acts as a benchmark

Jobs of a Forensic Scientist

• Assisting in investigations

• Recovering individuals from crime scene; esp. little bones

• Examining and analyzing human remains

• Reconstruct remains to analyze effects of trauma

Assessing Wounds: Sharp Instruments

• Slice/cut bone

• Type of instrument and the ANGLE of the cut can be determined

• RIBS are most likely to show signs of stabbings

Identifying Human Remains (Legally)

Closure is important, but there is a legal aspect; how did you prove they are actually, LEGALLY, dead?

• DEATH CERTIFICATE needed to collect insurance benefits, settle Wells, sell property, and allow surviving spouse to marry again

Medical History

One of the things you can determine from bones

• Osteomyelitis: Bone infection common in IV drug users; swelling of the bone

• Orthopedic PIns/Replaced Joints: Serial numbers can be used to identify

• Breaks/fractures: Remnant scar tissue and bone remodeling (the way bones heal has signatures that can be tracked)

Habitual Actions

One of the things you can determine from bones (part of the medical history)

Behavior that you constantly repeat can have an affect on how the bones appear

• Causes markings or shape CHANGE on bone

• Left/Right Handedness: Arthritic changes in shoulder on dominant side

Dental Work

One of the things you can determine from bones (part of medical history)

Teeth are VERY unique

• Fillings, crowns, dentures compared to

DNA

One of the things you can determine from bones

• DNA “expires” and degrades at some point; does not stay useful FOREVER

  • MITOCHONDRIAL DNA (separate from the DNA of the cell) is useful for tracing maternal parents

    • Less helpful; could only prove match on mom’s side

Five Functions of the Skeletal System

1) Internal structure & support

2) Protection of vital organs (heart, lungs, brain)

3) Attachment for muscles

4) To make blood cells

• Fluid (bone marrow) in the bones; makes red blood cells, platelets,

5) Storage of minerals

The 4 Shapes of Bones

1) Long

• Longer than they are wide

2) Short

• Length and width are about the same

3) Flat

• Thin

4) Irregular

• Funky shape that ISN’T thin

What is bone made of?

• Mostly collagen and dense materials including calcium phosphate

• Fossilization: Organic compounds replaced with various minerals overtime

• Made of a series of vertical tubes (osteons); each tube

Determining TIME of death (ALGOR MORTIS)

Algor Mortis: Cooling of the body after death

• On average, it’s going to cool 1-1.5 degrees F per hour under it matches environmental temperature

• Most effective within the first 12 hours of death

Factors to Consider…

• Environmental temp

• Type of clothing; was the clothing wet?

• Surface area/body mass ratio

  • SMALLER bodies cool more quickly

(98.4 F - internal temperature)/ (1.5 F/hr)

Determining TIME of death (LIVOR MORTIS)

Purple or red discoloration of the skin after death; caused by pooling in the blood due to gravity

• Begins ~30 mins after death

• Post 12 hrs, the discoloration won’t change regardless of how the body is moved

• Area IN CONTACT with ground, chain (any surface) will be whiter —> capillaries are compressed

Determining TIME of death (RIGOR MORTIS)

Stiffness in skeletal muscles

• Starts 2-3hrs after death, lasts until ~30 hrs

• SMALLER muscles stiffen first

Affected by…

• Temperature

• Dehydration

• Condition of muscles

• Use prior to death

Osteology

The study of bones

Animal vs. Human Bone

• Human bones are more random— circular osteons can be all different sizes

• Animal bones are more uniform; form in a pattern

  • Osteon Banding: Rows

  • Plexiform Bone: Rectangular shapes

Sexual Dimorphism

Structure/physical differences between a male and female

Difference in the Male & Female Pelvis

Pelvis differences can be used to determine SEX

Males

• Sacrum tilted forward

• Ilia closer together

• Subpubic angle is a cute

• NO prominent ventral arc

Female

• Sacrum titled back

• Ilia spread wider

• Subpubic angle is obtuse

• HAS a prominent ventral arc

Ventral Arc

The bony ridge on the front of the public bone, looks like its folding inwards

Estimating Height

Only can be done using LONG bones: humerus, radius, femur, tibia

• Accuracy deviates by ± 7.5 cm

Epiphyses

GROWTH plates at the end of long bones that fuse to the bone in early adulthood

• The greater the epiphyses; the more the person has to grow

Fusion of Sutures

One method of determining age

SAGITTAL SUTURE

• Completely fused closed between 26 and 32 years of age in MEN

• Completely fused closed between 29 and 35 of age in WOMEN

Age from the os pubis

One method of determining age

Os Pubis are the bones that connect on both sides to the pubis

• Furrows → YOUNGEST

• Smooth → MIDDLE

• Breakdown of Bone → OLDEST

Determining Ethnicity from Skull

MOST DIFFICULT to assess from the skeleton

• Not all are COMPLETELY ONE descent; mixed makes it more ambiguous

Caucasoid Skull

Consists of European, Middle Easter, and East Indian descent)

• Long, narrow nasal aperture

• Contains a nasal spine

• Triangular palate (roof of the mouth)

• Oval orbits

• Narrow zygomatic arches and mandibles

Negroid Skull

Consists of African, Aborigine, Melanesian descent)

• WIDEST nasal aperture

• NO a nasal spine

• Rectangular palate

• Square orbits

• More pronounced zygomatic arches han Caucasoid

• Maxilla bone projected outward → Prognathism

• Longer bones with less curvature & more DENSE

Mongoloid

Consists of Asian, Native America, Inut, Polynesian descent)

• More rounded nasal aperture

• Parabolic palate

• Rounded orbits

• MOST prominent zygomatic arches (cheek bones)

• Pointed Mandibles

• Shovel-shaped indentation in the back of upper front teeth

Dr. Thomas Dwight

Considered the “Father of American Forensic Anthropology"

• Taught at Harvard, first counted at the end of the 19th century

• Looked at clues to ID a person from bones

Dr. George Dorsey (1868 - 1931)

Another leading forensic anthropologist who also worked at Harvard

• Most known for the Luetgert murder case in Chicago

Luetgert Case

Adolph Luetgert murders his wife (Louisa Bicknese) and dissolves her body, but they found her ring and a couple bone fragments; able to be convicted of murder

• Led by Dr. George Dorsey

Dr. T.D. Stewart

Curator for the Smithsonian Institute

• Helped ID casualties from WWII and the Korean War

Central Identification Laboratory in Hawaii (CILHI)

Central spot (close to Pacific theatre, where many wars are fought)

• MAIN PURPOSE: Identify and repatriate American soldiers

How are remains analyzed by the CILHI

1) Teams sent out to different locations to try and find remains

2) Remains found are sent back to the base to be further analyzed

3) Statistical methods are used to differentiate remains of those from the native population

4) Biological profiles are created from the remains and compared to a database of all missing soldiers to try and find matches

Assessing Wounds: Dull Instruments

• Splinter/crushed bones

• Damage depends on the force, angle, # of times struck, type of instrument

• SEQUENCE of blows can be determined from the radiating fractures (like glass)

Assessing Wounds: Strangulation

• HYOID bone often damaged during manual strangulation

  • NOT in children because bones are still very flexible

Differences in Male and Female Skulls

FEMALE

1) Overall shape of the head

2) Supraorbital ridges → Slight; not as extreme as male skulls

3) Chin shape → Round chin

4) Orbital border → Sharp

5) Muscle attachments under the eye

6) Forehead → Rounded, vertical forehead

7) Protuberance in the back → Not as prominent as in males