INTRODUCTION

The analytical stage of forensic anthropology involves answering questions that lead to identification of the individual whose remains are being examined.  The questions asked in developing a biological or demographic profile for an individual include the following:

• What is the race of the individual?
• What is the sex of the individual?
• What is the age of the individual?
• What is the stature of the individual?
• What pathologies did the individual have?
• What traumas did the individual have?
• What idiosyncratic traits did the individual have?

OBJECTIVES

• to use anthropometric measuring instruments

• to recognize and assess skeletal indicators of stature.

• to practice carefully handling skeletal material.

READINGS

• Review Chapter 10 in the Byers textbook and bring your textbook to lab.

• Review Chapter 10 in the Byers lab workbook and bring your workbook to lab.

TERMS

• osteometric board
• stature
• regression formula
• potential stature
• living stature

GENERAL INSTRUCTIONS

Carefully handle the instructional casts and bones laid out in the lab, being sure to keep the bones with their labels.  Some of the ends of the bones where you will be making measurements are very delicate and will crumble if handled improperly.  Keep the materials on the bubble wrap to cushion them from the hard table surfaces, and wear gloves when working with real bones.

When working in a group, it is essential that all group members look at the bones and make the measurements.  If you don't do this, you risk missing points on the lab and the lab test.

Use reference books in the lab as needed.  Ask the instructor or assistant if you don't understand something. 
 

 STATURE ESTIMATION

The stature or height of an individual is useful information for making forensic identifications.  Before estimating stature, one must determine the race, sex, and age of the individual as stature varies with the variables.  Stature estimates are just that, estimates.  They are not exact and should always be expressed with a range of error.

Stature estimates are usually calculated in centimeters.  An individual who is 5 feet tall is about 152.4 cm tall (5 ft x 12 in/ft x 2.54 cm/in = 152.40 cm).  How tall in cm is a person who is 6 ft tall?  How tall in cm is a person who is 5 feet 6.5 inches tall?  Click here for the answers.

Stature estimates in centimeters are often converted to feet and inches since this form of information is most helpful to law enforcement officials.  To convert from cm to feet/inches, divide the cm value by 2.54 to convert to total inches.  Divide that answer by 12.  If the answer is less than 60, then the person was at least 4 feet tall.  If the answer is less than 72 but greater than or equal to 60, then the person was at least 5 feet tall.  If the answer is greater than or equal to 72, then the person was at least 6 feet tall.  Now you need to figure out the inches portion of the stature.  Take your total inches and subtract 48, 60 or 72 from it.  The remainder is the inches portion of the stature.  For example, a person who is 158.12 cm tall is 5' 2.25" tall:  158.12 / 2.54 = 62.25 inches  .....  this is between 60-72 so the person was at least 5 feet tall  ......   62.25 - 60 = 2.25 [2.25 inches]  .....   the stature is 5' 2.25'.  How tall in feet/inches is a person who is 173.36 cm? Click here for the answer.

For complete or nearly complete skeletons, stature is estimated using the skeletal height method, as we discussed in class.  For incomplete skeletons or isolated bones, stature is estimated by comparing the lengths of certain bones to tables of published data or by plugging lengths into published regression formulas.  The most commonly used bones for stature estimation of incomplete remains are the long bones (femur, tibia, fibula, humerus, ulna, radius), but short bones of the hands and feet may also be used. The use of two or more bones to estimate the stature of an individual improves the accuracy.

Potential stature refers to the stature of an individual who has not undergone skeletal changes associated with the aging process.  Most people who are less than 30 years old at the time of death have not undergone these changes.

Living stature refers to the stature of an individual who has undergone skeletal changes associated with the aging process that result in a decrease in stature.  Most people who are 30 years old or older at the time of death have undergone these changes.  Therefore, to account for the loss of height associated with aging, we must subtract from the stature estimates of older individuals.  To do this, we must know the age of the individual.  That age is plugged into the following equation, the answer of which is subtracted from the stature estimate:   0.06 * (age - 30) cm.  So, an individual who is 50 years old will likely have lost 1.20 cm of height (0.06 * 50-30 cm) due to the aging process.  How much height would a person of 62 years have likely lost?  Click here for the answer.  In this lab we will be estimating both potential stature and living stature, depending on the age of the individual.
 

ASSIGNMENT

The lab is due at the beginning of class on Thursday, April 17. Late labs will not be accepted.

Record your responses to the questions in pencil on the answer sheet provided in the lab.  

All estimates must include units (cm) and be reported as a range (e.g., 5'10.5" to 6'0.8" or 178.3 cm ± 3.83 cm).

There are six long bone specimens for this assignment.  Some are real bones, some are casts. 

For each specimen, you will be given race, sex, and age information.  Follow the following six steps for each specimen.  Examples are given on the answer sheet.

1.  Measure the maximum lengths of the long bone specimens using the osteometric board.  Exception:  For the tibia, measure from the distal end to the lateral condyle of proximal end; in other words, don't measure to intercondylar eminence.  All length measurements must be made to two decimal places (example: 33.23 cm, not 33.2 cm).  Record the lengths on the answer sheet.  Your answer must include units (cm).

2.  Based on race and sex, select the most appropriate regression formula to use in estimating stature for each specimen (using the table of formulas above).  Record the complete formula on your answer sheet.

3.  Plug your length measurement for each specimen into the appropriate formula and calculate the stature.  Record your estimate on the answer sheet.  Your answer must be calculated to two decimal places (example:  170.83 ± 3.41 cm, not 170.8 ± 3.41 cm).  Your answer must have the appropriate ± error.  Your answer must include units (cm).

4.  Calculate the potential stature range for each specimen.  This is accomplished by subtracting the error from your stature estimate and then adding the error to your stature estimate.  Record the range on the answer sheet.  Your answer must be calculated to two decimal places.  Your answer must include units (cm).

5.  If appropriate based on age, estimate the living stature range for each specimen.  Use the formula described in the Background section (above) to calculate the factor to be subtracted from the potential stature range and record that value (cm).  Record the range on the answer sheet.  Your answer must be calculated to two decimal places.  Your answer must include units (cm).  If you do not have to estimate the living stature for a particular specimen, write "Not Applicable" on the answer sheet.

6.  Convert the living stature range (or the potential stature range, if there is no living stature) for each specimen into feet and inches.  Record the range on the answer sheet.  Your inches answer should be rounded to one decimal place.  Your answer must include units (ft/in).

REFERENCES

Bass, W. M. (1987) Human Osteology: A Laboratory and Field Manual (3rd ed.). Missouri Archaeological Society, Columbia.

Byers, Stephen N.
2005 Introduction to Forensic Anthropology: A Textbook. Allyn and Bacon, Boston.

Byers, Stephen N. and Susan M.T. Myster
2005 Forensic Anthropology Laboratory Manual. Allyn and Bacon, Boston.

White, T. D. (1991) Human Osteology. Academic Press, San Diego.

**  6 ft x 12 in/ft x 2.54 cm/in = 182.90 cm
 

**  5 ft x 12 in/ft x 2.54 cm/in =                 150.00 cm
     + 6.5 in x 2.54 cm/in =                              16.51 cm
                                                                   166.51 cm
 

** 173.36 cm / 2.54 cm/in = 68.25        so 5 feet tall
     68.25 - 60 =   8.25 inches
      stature is 5' 8.25"
 

**  0.06 x (62 - 30) cm = 0.06 x 32 cm = 1.92 cm