Name: _________________________________________________ Unit 1 Lab

Analysis of Skeletal Remains Reference Website: http://shs2.westport.k12.ct.us/forensics/11-forensic_anthropology/skeletal_analysis_worksheet.htm

Background/Introduction: In the practice of forensic anthropology, scientists are asked to complete skeletal reconstructions as well as analyze the bones they found in order to identify the following:

● Gender (based on the pelvis & skull) ● Race (based on the maxilla, and other characteristics of the skull) ● Age (based on general characteristics) ● Height (calculated based on the length of individual bones)

Your job today will be to correctly identify the gender, age, and race based on photographs of skeletal remains. Gender Determination by Pelvis Many think the easiest way to determine gender is based on the height of the remains. The general thought is the taller the bones, the more likely it is that the skeleton belongs to a male. This is not always true, if you have a male that is shorter than the national average or a female who is taller than the average. There are several other ways to more accurately determine the gender of a skeleton. One of them is to analyze the pelvis, which is 95% accurate. The image below provides several different views of a male and female pelvis. Image 1:

Name: _________________________________________________ Unit 1 Lab

Use the information provided above; then circle the correct answers about the pelvises below:

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

Name: _________________________________________________ Unit 1 Lab

Gender Determination by Skull Another way to determine the gender of remains is by looking at the skull. Using the skull is not as accurate as using a pelvis, but is still 85 – 90% accurate. The table below lists nine “landmarks” for identification of a human skull. Landmarks are often for the attachment of muscles, the larger the muscle, the larger the landmark. On occasion, an athletic female’s landmarks can be confused with male’s landmarks.

Landmarks 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 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

Name: _________________________________________________ Unit 1 Lab

Use the information provided above; then circle the correct answers about the skulls below:

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 Male

Name: _________________________________________________ Unit 1 Lab

Determination of Race by Maxillary Bones There are several features that can be used to determine the race of an individual. One of the more useful places to look is at the skeleton’s maxillary bone. The left and right maxillary bones from the roof of the mouth, contain 16 teeth in the adult ( 10 teeth for children) and form the outline of the nasal cavity. The arch of the maxilla can be found in three basic shapes, hyperbolic, parabolic, and rounded.

● African descent generally have a hyperbolic shaped maxilla ● European descent generally have a parabolic shaped maxilla ● Asian descent generally have a round shaped maxilla ● Members of Hispanic descent do not have a specific maxilla shape listed

The incisors fall into two basic categories based on the shape of the lingual (tongue) surface of the tooth. These two categories are: (1) shovel-shaped and (2) saptulate, or spatula-shaped. As there is more than one race with spatulate incisors, other indicators are necessary to positively identify race, although this single feature can be used to eliminate one of the possibilities. Each of the following three races have their own shape:

● African descent generally have spatulate ● European descent generally have spatulate ● Asian descent generally have shovel-shaped ● Members of Hispanic descent do not have a specific lingual surface type listed

Based upon the information provided above, determine the race of each of the three maxilla shown below:

Name: _________________________________________________ Unit 1 Lab

Maxilla 1 Maxilla 2 Maxilla 3

Arch Shape Hyperbola, Parabola, or Rounded

Arch Shape Hyperbola, Parabola, or Rounded

Arch Shape Hyperbola, Parabola, or Rounded

Incisor Spatulate or Shovel-shaped Incisor Spatulate or Shovel-shaped Incisor Spatulate or Shovel-shaped

RACE: African Asian Caucasian

RACE: African Asian Caucasian

RACE: African Asian Caucasian

Name: _________________________________________________ Unit 1 Lab

Age Determination by Bone Condition A forensic anthropologist can start to determine the age of the remains by simply looking at the overall condition of the bones. Older bones are more likely to be arthritic with calcium deposits making the bones appear rigid and warped. Use the images below to determine if the bones are arthritic and if they belong to a young or older person.

Arthritic Yes OR NO Arthritic Yes OR NO Younger OR Older Younger OR Older

Name: _________________________________________________ Unit 1 Lab

Age Determination by Development of Structures Forensic anthropologists can determine age by looking at the development of the sutures on a skull. Sutures are fibrous joints that allow for the slight compliance and elasticity of the skull. In children the sutures have not fully developed, leaving “gaps” in the skull. Adults however, have fully developed sutures and the gaps have been completely filled. Image 2 below is not to scale but does show the presence and absence of sutures. Image 2:

Name: _________________________________________________ Unit 1 Lab

Use the information provided above to determine if the skulls below belong to a child or an adult.

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

Name: _________________________________________________ Unit 1 Lab

Questions: 1. What is the easiest way to determine the gender (using a skeleton) of an individual? 2. What is the easiest way to tell if a skeleton belonged to a teenager or an older adult? 3. Why can determining gender from a skull be difficult? 4. What scientific practices did you use during this activity (refer to purple sheet)? Explain your reasoning with specific detail please. 5. What if the skeleton was of mixed races, how might you go about determining the race?