Objective

Describe Forensic Anthropology and how it is used to solve crimes.

Warm-Up: Video

http://www.hulu.com/watch/474025#i0,p0,d0

As you watch the video, write down key words/identifiers of victim’s age.

Let the bones tell the story! Image: http://upload.wikimedia.org/wikipedia/commons/4/4c/Punuk.Alaska.skulls.jpg

Presentation developed by T. Trimpe 2010 http://sciencespot.net

What role do anthropologists play in solving crimes?Watch the video and then answer the questions.

1. What does a physical anthropologist investigate?

2. What four things do we want to know about a skeleton?

3. What bones are most useful for developing a profile of a person? Explain how they are used.

HOW MANY BONES ARE IN THE ADULT HUMAN BODY?

206

What is bone?

Living tissue made of cells within a matrix of protein (mostly collagen) and minerals (calcium and phosphorous)

The skeleton is one part of the body that takes the longest to decayBones can last for 100s to 1,000s of

years

Source: http://anthropology.si.edu/writteninbone/bone_basics.html

Simple Composition of Bones

Outer layer: smooth, compact bones

Inner layer: spongy, porous bone Bone Marrow –

responsible for producing red & white blood cells

Left femur (thigh bone), coronal section Image courtesy of: Smithsonian National Museum of Natural HistorySource: http://anthropology.si.edu/writteninbone/index.htmlcc

More Accurate Composition of Bones

Clues for determining age lie within the Epiphysis:

Source; http://www.bbc.co.uk/schools/gcsebitesize/pe/appliedanatomy/2_anatomy_skeleton_rev4.shtml

Determining Age - Epiphysis

Ossification of cartilage creates bone

Source: http://www.bbc.co.uk/schools/gcsebitesize/pe/images/bone_growth.gif

Technology for Determining Age

An x-ray image (radiograph) of a child will reveal a dark area where the growth plates are still made of cartilage (more x-rays can pass through cartilage, which is less dense, thus making a dark area); these areas are the epiphyseal plates. 

An x-ray radiograph of an adult will reveal a white area where the growth plates have been turned into bone (fewer x-rays can pass through bone, which is more dense, thus making a white line); these areas are the epiphyseal lines. 

Circle the Appropriate Answer

Epiphyseal Plate   or   Line Epiphyseal Plate   or   Line

Adult   or   Child Adult   or   Child

Facts about Aging

Normal growth stops around Age 17-25Clavicle is last bone to stop growing (age

25)Tibia completes growth by:

Age 16-17 (female)Age 18-19 (male)

Clavicle. Image courtesy of: Smithsonian Institution

Source: http://anthropology.si.edu/writteninbone/index.htmlcc

Determining Age

Children Teeth are best age

indicator Higher presence of

cartilage in epiphysis Length of long bones is

good indicator for estimation of age

Adults Pelvis best age indicator Cranium, pubic bone

and rib ends hold information to determine age

Osteons – smaller osteons

Cranial sutures Arthritis

Source: http://anthropology.si.edu/writteninbone/index.html

Like Fingerprints… just can’t be seen until antemortem

Adult skull has no remaining suture (called the frontal suture) in the middle of the Frontal bone.

Remember, also, that all the sutures ultimately become more filled-in ("closed") as we age.

Circle the Appropriate Answer

Frontal Suture Present   or   Absent Frontal Suture Present   or   Absent

Other Sutures "Open"   or   "Closed" Other Sutures "Open"   or   "Closed"

Adolescent   or   Adult Adolescent   or   Adult

Male or Female?

Male Narrower, heart-shaped pelvic

inlet Narrower sciatic notch Narrower angle where the two

pubic bones meet in front

Open, circular pelvic inlet Broader sciatic notch Wider angle where the two

pubic bones meet in front More outwardly flared hip

bones

Female

Source: http://anthropology.si.edu/writteninbone/index.html

[Left] Male pelvis. [Right] Female pelvis.Image courtesy: Smithsonian Institution

Gender- Pelvis

Try it out

•

Angle > 90 degrees   or   < 90 degrees Angle > 90 degrees   or   < 90 degrees

Sacrum Forward   or   Backward Sacrum Forward   or   Backward

Pelvic Outlet Small   or   Large Pelvic Outlet Small   or   Large

Ilia Close   or   Spread Ilia Close   or   Spread

Female   or   Male Female   or   Male

Gender Differences in the SkullLandmarks Female Male

Chin Rounded Square

Mastoid Process(Behind Ear)

Small Large

External Occipital Protuberance(Back of Skull)

Small(Not Prominent)

Large(Prominent)

General Anatomy Gracile (i.e., Graceful) Robust

Forehead Vertical Receding(Careful with the comments . . .)

Brow Ridges(Location of Eyebrows)

Slightly Developed Prominent

Muscle Lines Slightly Developed Prominent

Orbital Margins(Edge of Eye Socket)

Sharp Rounded

Angle of Ascending Ramus(Back Corner of the Jaw)

Obtuse Close to 90 degrees

Circle the Appropriate Answer

Chin Rounded   or   Square Chin Rounded   or   Square

Mastoid Process Small   or   Large Mastoid Process Small   or   Large

Occipital Protuberance Small   or   Large Occipital Protuberance Small   or   Large

General Anatomy Gracile   or   Robust General Anatomy Gracile   or   Robust

Forehead Vertical   or   Receding Forehead Vertical   or   Receding

Brow Ridges Slight   or   Prominent Brow Ridges Slight   or   Prominent

Muscle Lines Slight   or   Prominent Muscle Lines Slight   or   Prominent

Orbital Margins Sharp   or   Rounded Orbital Margins Sharp   or   Rounded

Angle of Ramus 90 degrees   or   Obtuse Angle of Ramus 90 degrees   or   Obtuse

Gender Female   or   Male Gender Female   or   Mal

Source: http://www.crime-scene-investigator.net/excavation.html Images: http://www.wadsworth.com/anthropology_d/special_features/forensics/forensics_index/index.html

FORENSIC ANTHROPOLOGISTS analyze skeletal remains to determine the identity of a victim as well as his/her life history, cause of death, or other clues about a crime.

Main Characteristics:

 Sex - Determined by examining the skull, pelvis, humerus, and femur

Age and stature (height/build) – Determined by analyzing the development of the teeth, bone growth, cranial suture lines, and the length of specific bones, such as the femur.

Race – Determined by analyzing the skull for characteristics that are common among people of different races.

Career ConnectionWhat does a forensic anthropologist do?

Which skull would belong to a female?

Which pelvis would belong to a female?

Warm-Up: Video

http://www.hulu.com/watch/474025#i0,p0,d0

As you watch the video, again write down key words/identifiers of victim’s age.

During the second viewing, assess whether or not you think Dr. Brenan used accurate anthropological data to determine sex and age of victim

Questions:

What is the easiest way to determine the gender (using the skeleton) of an individual, and why?

What is the easiest way to tell (using the skeleton) whether a teenager is lying about her/his age, and why?

Why can determining gender from a skull be difficult? Why should a forensic anthropologist use more than

one bone (if possible) to determine the height of an individual?

What other issue is important to question four, especially if there is only one bone from which to work?