TRAINING LAB – SKELETAL REMAINS: DETERMINING A VICTIM’S HEIGHT
NAME___________________________________________ Background: As a Forensic Anthropologist you have been trained to identify skeletal remains – but what can the bones you identify tell you about the victim? One important piece of information a bone can help you uncover is the victim’s approximate height. Knowing the victim’s height can be an important first step in discovering the victim’s identity. 1. You will be trained to analyze skeletal remains to determine a victim’s height. Procedures:
Part 1 – Measuring Your Own Bones To Determine Your Height 1. Use a meter stick and accurately measure the length of your Femur to the nearest 0.5 centimeter. Record your measurement in Table 1. 2. Repeat Step #1 and measure the length of your Tibia, Humerus, and Ulna to the nearest 0.5 centimeter. Record these measurements in Table 1. 3. Finally, measure your height to the nearest 0.5 centimeter. Record your height in Table 1. 4. Anthropologists have measured the heights and bone lengths of many humans to see if there is a relationship between bone length and height. After analyzing a large mass of data they discovered a distinct relationship between bones and height. Formulas were derived from this data that will allow a Forensic Anthropologist to measure the length of a single bone from a person and calculate that person’s approximate height (the height is usually accurate to 1 or 2 inches). These important formulas can be found in Table 2. 5. Use your Femur length measurement (from Table 1) and the correct Femur formula (from Table 2) to calculate your approximate height in centimeters. Record your Calculated Height in Table 1. 6. Repeat Step #5 to calculate your approximate height using your Tibia, Humerus, and Ulna length measurements. Check carefully to make sure you are using the correct formula for each calculation. Record each Calculated Height in Table 1. 7. Convert all your Table 1 Centimeter Heights (Actual and Calculated) into the more familiar Feet and Inches. Follow these simple steps: Step #1 – Use the following Formula to convert centimeters into inches. Round your answers to the nearest inch. Step #2 – Convert total Inches to Feet and Inches (48 inches = 4 feet, 60 inches = 5 feet, 72 inches = 6 feet). EXAMPLE: 65 inches = 5 feet 5 inches Record all Feet and Inch heights in Table 1.
Height in Inches = 2.54 Centimeters per Inch
Height in Centimeters
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Part 2 – Measuring Skeletal Remains To Determine A Victim’s Height
1. Your Supervisor has a collection of skeletal remains from various crime scenes that have been sent to you for analysis. Studies of the skulls found with these bones helped investigators determine each victim’s race and sex. They need your help to determine each victim’s approximate height. Below is the information that is known about each of the bones.
Measure the total lengths of each of the bones as accurately as possible. Determine the Approximate Height (in Feet and Inches) of each of the victims. Record your results in Table 3. Part 3 – Using Height Calculations To Analyze A Crime Scene
1. A shallow grave, filled with the skeletal remains of what is believed to be at least two people, was recently discovered in a nearby county. Only a mix of arm and leg bones were found in the grave, which has made it difficult for the sheriff’s department to determine exactly how many victims were buried. The sheriff’s department carefully measured each bone’s length (bone length is the only information they have been able to gather from the skeletal remains). This bone length data just arrived in our lab today. They would like for you to use height calculations to help determine the number of victims in the grave. 2. The bone length data can be found in Table 4 – “Bone Evidence Summary Sheet”. Complete the “Bone Evidence Summary Sheet” so we can send the results back to the Sheriff’s Department.
Bone Name Race Sex
Ulna Caucasian Male
Femur African-American Female
Fibula Unknown Unknown
Radius Asian Male
Tibia African-American Male
Humerus Caucasian Female
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DATA TABLES – SKELETAL REMAINS: DETERMINING A VICTIM’S HEIGHT
NAME___________________________________________
Bone NameBone Length
(cm)
Calculated
Height
(cm)
Calculated
Height
(inches)
Calculated
Height
(ft./inches)
Femur
Tibia
Humerus
Ulna
My Actual Height (cm)
My Actual Height (inches)
My Actual Height (ft/inches)
Table 1 – My bone lengths and calculated height
Bone NameBone Length
(cm)
Calculated
Height
(cm)
Calculated
Height
(inches)
Calculated
Height
(ft./inches)
Ulna
Femur
Fibula
Radius
Tibia
Humerus
Table 3 – Estimated heights calculated from skeletal remains
359
How many different victims do you believe were buried in the mass grave? List the Estimated Height of each victim below. Next to each victim’s height write the number of bones from the grave that you believe belong to that victim.
Bone NameBone Length
(cm)
Calculated
Height
(cm)
Calculated
Height
(inches)
Calculated
Height
(ft./inches)
Ulna 24cm
Femur 45cm
Fibula 34cm
Humerus 32cm
Humerus 30cm
Radius 24.5cm
Femur 41cm
Tibia 36.5cm
Fibula 39cm
Radius 24.5cm
Tibia 33.5cm
Radius 26.5cm
Femur 48cm
Humerus 36cm
Table 4 – Bone Evidence Summary Sheet
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Table 2 – Formulas used to calculate Estimated Height (cm) from Bone Length (all bone measurements MUST be made in Centimeters)
Bone Name Race Male Female
Caucasian (2.89 x length) + 78.10cm (3.36 x length) + 57.97cm
African-American (2.88 x length) + 75.48cm (3.08 x length) + 64.67cm
Asian (2.68 x length) + 83.19cm use unknown formula
Unknown
Caucasian (3.79 x length) + 79.42cm (4.74 x length) + 54.93cm
African-American (3.32 x length) + 85.43cm (3.67 x length) + 71.79cm
Asian (3.54 x length) + 82.00cm use unknown formula
Unknown
Caucasian (3.76 x length) + 75.55cm (4.27 x length) + 57.76cm
African-American (3.20 x length) + 82.77cm (3.31 x length) + 75.38cm
Asian (3.48 x length) + 77.45cm use unknown formula
Unknown
Caucasian (2.32 x length) + 65.53cm (2.47 x length) + 54.13cm
African-American (2.10 x length) + 72.22cm (2.28 x length) + 59.76cm
Asian (2.15 x length) + 72.57cm use unknown formula
Unknown
Caucasian (2.42 x length) + 81.93cm (2.90 x length) + 61.53cm
African-American (2.19 x length) + 85.36cm (2.45 x length) + 72.56cm
Asian (2.39 x length) + 81.45cm use unknown formula
Unknown
Caucasian (2.60 x length) + 75.50cm (2.93 x length) + 59.61cm
African-American (2.34 x length) + 80.07cm (2.49 x length) + 70.90cm
Asian (2.40 x length) + 80.56cm use unknown formula
Unknown
Ulna
Femur
Tibia
Fibula
(4.62 x length) + 19.00cm
(3.78 x length) + 74.7cm
(4.61 x length) + 46.83cm
(2.71 x length) + 45.86cm
(3.29 x length) + 47.34cm
(3.59 x length) + 36.31cm
Humerus
Radius
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QUESTIONS – SKELETAL REMAINS: DETERMINING A VICTIM’S HEIGHT
NAME________________________________
1. On the average, how far off (in inches) were your calculated heights from your actual height? 2. Which of your bone(s) gave you the most accurate estimation of your actual height? 3. Which of your bone(s) gave you the least accurate estimation of your actual height? 4. The formulas that you used for calculating your estimated height are based on measurements from adult bones. How could this affect your calculated height results? 5. Why would knowing the sex of a bone allow you to make a more accurate estimation of the victim’s height? 6. You measure a bone and calculate the height of the victim is 5 feet 11 inches. Why is it correct to say that this is the victim’s Estimated Height?
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TEACHER NOTES Lab/Activity: Training Lab – Skeletal Remains: Determining A Victim’s
Height Equipment To Prepare: 1 meter stick/group – to measure the lengths of bones 1 “Height Measuring” Station – students will need to measure their correct height (in cm)
during the Training Lab. This process can be sped up by taping two meter sticks to a a wall (one from the floor up and the second continuing onward from the end of the first). Students can stand in front of the two meter sticks and a third meter stick (or similar) can be placed flat on the student’s head to help determine their correct height.
1 calculator/group – to calculate heights 1 each of the following bones placed in a tray or a central location for student access (these can be a random assortment of right or left bones from different disarticulated sets). However, if you have female disarticulated bones you could place female bones for the Femur and Humerus – although male bones will work fine for all. The bones should not be labeled in any way. 1 Humerus (female) 1 Femur (female) 1 Radius 1 Tibia 1 Ulna 1 Fibula These bones will be used for Part 2 of the Training Lab. All the students in the class can use these same bones SIX bones (it doesn’t take long to measure the length of a
bone – so their isn’t much wait time). You should also measure the lengths of the SIX bones you use, calculate approximate
heights (according to the instructions in Part 2 of the Training Lab), and record these results in the supplied KEY (found after these Teacher Notes).
Comments/Problems: This Training Lab usually takes 1 day to complete if students measure and calculate very quickly. Otherwise, it will spill over to a second day. The formulas used in the Training Lab came from Bass, W.M. (1987), Human Osteology: A Laboratory and Field Manual. Students sometimes find great variability when calculating their own heights from bone lengths. This is often due to inaccurate measurements (it is harder to measure the length of a bone when it is inside your body), the fact that the bone formulas are based on adult bones, and the fact that the calculations give an approximate height only.
Typical Results: Keys to the Training Lab Tables and Questions follow these Teacher Notes.
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DATA TABLES – SKELETAL REMAINS: DETERMINING A VICTIM’S HEIGHT
NAME___________________________________________
Bone NameBone Length
(cm)
Calculated
Height
(cm)
Calculated
Height
(inches)
Calculated
Height
(ft./inches)
Femur
Tibia
Humerus
Ulna
My Actual Height (cm)
My Actual Height (inches)
My Actual Height (ft/inches)
Table 1 – My bone lengths and calculated height
Bone NameBone Length
(cm)
Calculated
Height
(cm)
Calculated
Height
(inches)
Calculated
Height
(ft./inches)
Ulna
Femur
Fibula
Radius
Tibia
Humerus
Table 3 – Estimated heights calculated from skeletal remains
KEY
ANSWERS WILL VARY FOR EACH STUDENT
MEASURE THE BONES YOU USE, CALCULATE HEIGHTS,
AND RECORD HERE.
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How many different victims do you believe were buried in the mass grave? List the Estimated Height of each victim below. Next to each victim’s height write the number of bones from the grave that you believe belong to that victim.
Table 4 – Bone Evidence Summary Sheet
Bone NameBone Length
(cm)
Calculated
Height
(cm)
Calculated
Height
(inches)
Calculated
Height
(ft./inches)
Ulna 24cm 157.47 62 5' 2"
Femur 45cm 167.81 66 5' 6"
Fibula 34cm 158.37 62 5' 2"
Humerus 32cm 166.84 66 5' 6"
Humerus 30cm 157.6 62 5' 2"
Radius 24.5cm 167.31 66 5' 6"
Femur 41cm 156.97 62 5' 2"
Tibia 36.5cm 167.43 66 5' 6"
Fibula 39cm 176.32 69 5' 9"
Radius 24.5cm 167.31 66 5' 6"
Tibia 33.5cm 157.56 62 5' 2"
Radius 26.5cm 174.87 69 5' 9"
Femur 48cm 175.94 69 5' 9"
Humerus 36cm 185.32 73 6' 1"
4
Victim #1 Height = 5’ 2” 5 bones Victim #2 Height = 5’ 6” 5 bones Victim #3 Height = 5’ 9” 3 bones Victim #4 Height = 6’ 1” 1 bone
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QUESTIONS – SKELETAL REMAINS: DETERMINING A VICTIM’S HEIGHT
NAME________________________________
1. On the average, how far off (in inches) were your calculated heights from your actual height? 2. Which of your bone(s) gave you the most accurate estimation of your actual height? 3. Which of your bone(s) gave you the least accurate estimation of your actual height? 4. The formulas that you used for calculating your estimated height are based on measurements from adult bones. How could this affect your calculated height results? 5. Why would knowing the sex of a bone allow you to make a more accurate estimation of the victim’s height? 6. You measure a bone and calculate the height of the victim is 5 feet 11 inches. Why is it correct to say that this is the victim’s Estimated Height?
KEY
ANSWERS WILL VARY – SOME WILL BE VERY CLOSE, WHILE OTHERS WILL VARY GREATLY
ANSWERS WILL VARY
ANSWERS WILL VARY
STUDENTS ARE STILL GROWING, THEREFORE, IT IS MORE LIKELY THAT CALCULATED HEIGHTS WOULD BE INCORRECT AND SHOW MORE VARIATION.
FEMALE BONES ARE TYPICALLY SHORTER THAN MALE BONES. CALCULATIONS WOULD BE MORE ACCURATE IF THE FORMULA IS BASED ON FEMALE BONES ONLY – RATHER THAN USING A FORMULA THAT AVERAGES BOTH MALE AND FEMALE BONE LENGTHS TOGETHER.
THESE FORMULAS ARE BASED ON AVERAGE BONE LENGTHS. SOME PEOPLE MAY BE SOMEWHAT TALLER THAN THE CALCULATED HEIGHT, WHILE OTHERS MAY BE SOMEWHAT SHORTER THAN THE CALCULATED HEIGHT. CALCULATED HEIGHTS SHOULD ALWAYS BE REPORTED AS “ESTIMATED” HEIGHT.
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TRAINING LAB – SKELETAL REMAINS: DETERMINING A VICTIM’S SEX
NAME___________________________________________ Background: Humans look different from each other on the outside – each of us with our own external characteristics. We can easily recognize males and females, and one individual from another, because we have had years of experience observing these external differences. Forensic Anthropologists have also discovered male and female differences in a part of the body we’re NOT used to observing – the male and female skeletal system. Not only can a victim’s approximate height be determined by skeletal remains, but the sex of the victim can also be determined with a fair degree of accuracy – especially after you have had years of practice. 1. You will be trained to analyze skeletal remains to determine if a victim is a male or a female. Procedures:
There are several different bones that can help determine if skeletal remains came from a male or female victim. In this Training Lab you will work with the bones that are most commonly used by Forensic Anthropologists for sex determination. You do NOT have to begin with Part 1 for this Training Lab. If other groups are using the Part 1 skulls you should move on to another section of the lab and come back to Part 1 later.
Part 1 – Using The Skull And Mandible For Sex Determination 1. Your Supervisor has set out skulls for you to observe. You may be asked to observe one or two different numbered skulls (your Supervisor will tell you how many different skulls you should observe). 2. Bring one of the skulls back to your lab station. Please DO NOT point to parts of the skull with your pen or pencil and mark on the skull. 3. Write the number of the skull you are observing in Table 5 – “Sex Determination Of Skeletal Remains - SKULL” (the number can be found on the top of the skull). 4. Carefully observe the characteristics of your skull using Table 1 – “Characteristics of Male and Female Skulls” as your guide (Table 1 can be found on the next page). This Table describes Male and Female characteristics that are generally visible on skulls. Labeled diagrams of Male and Female skulls/mandibles have also been included to assist you. 5. Record each of your skull’s characteristics in Table 5. Record your observation in the “Male” column if you observed a Male characteristic, in the “Female” column if you observed a Female characteristic, and in the “Can’t Determine” column if the observed characteristic seemed to be between Male and Female. 6. Look at all your observations and decide if you have a Male or Female skull (do you have more characteristics recorded in the Male or Female column)? Record your final result in Table 5. 7. Repeat Steps #3 - #6 for a second skull (if supplied by your Supervisor). 8. Check the KEY found in the front of the room to see if your conclusions are correct!
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AREA OF
SKULLMALE FEMALE
ForeheadFrom A Side View - Appears to be
sloping backward
From A Side View - Appears to be more
straight up and down
Orbit
ShapeUsually more square-shaped Usually more round-shaped
Upper Edge
Of OrbitMore of a rounded, less sharp edge More of a sharp edge
Mastoid
ProcessLarger Smaller
External Occipital
Protuberance Larger Small or missing
Mandible
AngleCloser to a 90
o Angle Angle much larger than 90
o
Chin Shape More of a square shape More of a rounded, pointy shape
Table 1 - Characteristics of Male and Female Skulls
More square orbit shape
Upper orbit has more of a rounded edge
Chin shape is more square
More rounded orbit shape
Upper orbit has more of a
sharp edge
Chin shape is more rounded/pointy
Sloping forehead
Mastoid process larger
External Occipital
Protuberance larger
Mandible Angle closer to 900
Straight forehead
Mastoid process smaller
External Occipital
Protuberance small or missing
Mandible Angle much larger than 900
MALE SKULL/MANDIBLE FEMALE SKULL/MANDIBLE
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Part 2 – Using The Pelvis (Coxal Bones, Sacrum, Coccyx) For Sex
Determination 1. The next bone to observe is the Pelvis. You may be asked to observe more than one numbered Pelvis (your Supervisor will tell you how many you should observe). 2. Bring a Pelvis back to your lab station. Please DO NOT point to parts of the Pelvis with your pen or pencil and make marks on the bone. 3. Write the number of the Pelvis you are observing in Table 6 – “Sex Determination Of Skeletal Remains - PELVIS”. 4. Carefully observe the characteristics of your Pelvis using Table 2 – “Characteristics of The Male and Female Pelvis” as your guide (Table 2 can be found below). Labeled diagrams of the Male and Female Pelvis have also been included to assist you. 5. Record each of your Pelvis’s characteristics in Table 6. Record your observation in the “Male” column if you observed a Male characteristic, in the “Female” column if you observed a Female characteristic, and in the “Can’t Determine” column if the observed characteristic seemed to be between Male and Female. 6. Look at all your observations and decide if you have a Male or Female Pelvis (do you have more characteristics recorded in the Male or Female column)? Record your final result in Table 6. 7. Repeat Steps #3 - #6 for a second Pelvis (if supplied by your Supervisor). 8. Check the KEY found in the front of the room to see if your conclusions are correct!
AREA OF
PELVISMALE FEMALE
Front View Of The
Subpubic AngleLess than a 90
o angle
Like a "V" shape
90o angle or larger angle
Like an "L" shape
Top View Of The
Pelvic Cavity Shape
The space you see inside is more
"heart" shaped and small
The space you see inside is more
oval/circular in shape and larger
Sacrum Shape
Sacrum is longer and thinner.
The Sacrum and coccyx are tilted
toward the inside of the Pelvic
Cavity and are easily visible from
a top view.
Sacrum is shorter and wider. The
Sacrum and coccyx are tilted
backward away from the Pelvic
Cavity and are not very visible
from a top view.
Pubic Bone Width
(in mm) From The
Center Of The Pubis
Symphysis To The
Obterator Foramen
(the large hole)
Measure with a ruler (mm). The
Pubic Bone Width at this location
is less than 30mm.
Measure with a ruler (mm). The
Pubic Bone Width at this location
is greater than 35mm.
**PUBIS SYMPHYSIS** where the two coxal bones meet in the front (ventral)
Table 2 – Characteristics of the Male and Female Pelvis
369
IF YOU ONLY HAVE ONE COXAL BONE 1. You can still accurately estimate what the subpubic angle would be (less than or greater than 900). 2. You can still measure the width of the Pubic Bone from the center of the Pubis Symphysis to the Obturator Foramen.
#1 – Subpubic Angle
#2 – width
of the Pubic
Bone here
Top view of pelvic cavity – space is
small and “heart” shaped
Sacrum is tilted inward with
coccyx pointing into the space
Top view of pelvic cavity – space is large and oval or circular shaped
Sacrum is tilted backward with coccyx barely
pointing into the space
MALE PELVIS
Sacrum longer and thinner
Front view of subpubic angle is less than 900
“V-shaped”
Measure the width of the pubic bone here (in mm). If it is less than 30mm = Male,
greater than 35mm = Female
FEMALE PELVIS
Front view of subpubic angle is greater than 900
“L-shaped”
Sacrum shorter and wider
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Part 3 – Using The Humerus For Sex Determination 1. The next bone to observe is the Humerus. You may be asked to observe more than one numbered Humerus (your Supervisor will tell you how many you should observe). 2. Bring a Humerus back to your lab station. Please DO NOT point to parts of the Humerus with your pen or pencil and make marks on the bone. 3. Write the number of the Humerus you are observing in Table 7 – “Sex Determination Of Skeletal Remains - HUMERUS”. 4. Carefully observe the characteristics of your Humerus using Table 3 – “Characteristics of the Male and Female Humerus” as your guide (Table 3 can be found below). You will be taking measurements of the Humerus (in millimeters) to determine sex. You can either place a millimeter ruler behind the Humerus when taking measurements, or you can use a caliper (for a more accurate measurement) if one is available. 5. Record each of your Humerus’s characteristics in Table 7. Record your observation in the “Male” column if you observed a Male characteristic, in the “Female” column if you observed a Female characteristic, and in the “Can’t Determine” column if the observed characteristic seemed to be between Male and Female. 6. Look at all your observations and decide if you have a Male or Female Humerus (do you have more characteristics recorded in the Male or Female column)? Record your final result in Table 7. 7. Repeat Steps #3 - #6 for a second Humerus (if supplied by your Supervisor). 8. Check the KEY found in the front of the room to see if your conclusions are correct!
Width Between Epicondyles
Dorsal View Of The Humerus Transverse
Diameter of Head
Vertical Diameter of
Head
MEASUREMENTS
OF THE HUMERUSMALE
COULD BE MALE
OR FEMALEFEMALE
Transverse Diameter
Of The Head
greater than
47 mm43 to 47 mm
less than
43 mm
Vertical Diameter
Of The Headcloser to 48.8 mm 45.8 mm closer to 42.7 mm
Width Between
Epicondylescloser to 63.9 mm 60.4 mm closer to 56.8 mm
Total Length Of The
Humeruscloser to 339.0 mm 322.5 mm closer to 305.9 mm
Table 3 – Characteristics of the Male and Female Humerus
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