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. Height in Centimeters Height in Inches = 2.54 Centimeters per 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. 357 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. Bone Name Race Sex Ulna Caucasian Male Femur African-American Female Fibula Unknown Unknown Radius Asian Male Tibia African-American Male Humerus Caucasian Female 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. 358 DATA TABLES – SKELETAL REMAINS: DETERMINING A VICTIM’S HEIGHT NAME___________________________________________ Table 1 – My bone lengths and calculated height Bone Name Bone 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 3 – Estimated heights calculated from skeletal remains Bone Name Bone Length (cm) Calculated Height (cm) Ulna Femur Fibula Radius Tibia Humerus 359 Calculated Height (inches) Calculated Height (ft./inches) Table 4 – Bone Evidence Summary Sheet Bone Name Bone Length (cm) 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 Calculated Height (cm) Calculated Height (inches) Calculated Height (ft./inches) 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. 360 Table 2 – Formulas used to calculate Estimated Height (cm) from Bone Length (all bone measurements MUST be made in Centimeters) Bone Name Humerus 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 (4.62 x length) + 19.00cm Unknown Radius 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 (3.78 x length) + 74.7cm Unknown Ulna 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 (4.61 x length) + 46.83cm Unknown Femur 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 (2.71 x length) + 45.86cm Unknown Tibia 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 (3.29 x length) + 47.34cm Unknown Fibula 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 (3.59 x length) + 36.31cm Unknown 361 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? 362 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. 363 DATA TABLES – SKELETAL REMAINS: DETERMINING A VICTIM’S HEIGHT KEY NAME___________________________________________ Table 1 – My bone lengths and calculated height Bone Name Bone Length (cm) Calculated Height (cm) Calculated Height (inches) Calculated Height (ft./inches) Femur Tibia Humerus Ulna ANSWERS WILL VARY FOR EACH STUDENT My Actual Height (cm) My Actual Height (inches) MEASURE THE BONES YOU USE, CALCULATE HEIGHTS, AND RECORD HERE. Table 3 – Estimated heights calculated from skeletal remains My Actual Height (ft/inches) Bone Name Bone Length (cm) Calculated Height (cm) Ulna Femur Fibula Radius Tibia Humerus 364 Calculated Height (inches) Calculated Height (ft./inches) Table 4 – Bone Evidence Summary Sheet Bone Name Bone 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" How many different victims do you believe were buried in the mass grave? 4 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. 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 365 QUESTIONS – SKELETAL REMAINS: DETERMINING A VICTIM’S HEIGHT KEY NAME________________________________ 1. On the average, how far off (in inches) were your calculated heights from your actual height? ANSWERS WILL VARY – SOME WILL BE VERY CLOSE, WHILE OTHERS WILL VARY GREATLY 2. Which of your bone(s) gave you the most accurate estimation of your actual height? ANSWERS WILL VARY 3. Which of your bone(s) gave you the least accurate estimation of your actual height? ANSWERS WILL VARY 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? STUDENTS ARE STILL GROWING, THEREFORE, IT IS MORE LIKELY THAT CALCULATED HEIGHTS WOULD BE INCORRECT AND SHOW MORE VARIATION. 5. Why would knowing the sex of a bone allow you to make a more accurate estimation of the victim’s height? 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. 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? 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. 366 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! 367 Table 1 - Characteristics of Male and Female Skulls AREA OF SKULL MALE FEMALE Forehead From A Side View - Appears to be sloping backward From A Side View - Appears to be more straight up and down Usually more square-shaped Usually more round-shaped More of a rounded, less sharp edge More of a sharp edge Larger Smaller Larger Small or missing Orbit Shape Upper Edge Of Orbit Mastoid Process External Occipital Protuberance Mandible Angle Chin Shape o Angle much larger than 90 More of a square shape More of a rounded, pointy shape MALE SKULL/MANDIBLE FEMALE SKULL/MANDIBLE Upper orbit has more of a sharp edge Upper orbit has more of a rounded edge More square orbit shape Chin shape is more square More rounded orbit shape Chin shape is more rounded/pointy Sloping forehead External Occipital Protuberance larger Straight forehead External Occipital Protuberance small or missing Mastoid process smaller Mastoid process larger Mandible Angle closer to 900 o Closer to a 90 Angle Mandible Angle much larger than 900 368 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! Table 2 – Characteristics of the Male and Female Pelvis AREA OF PELVIS Front View Of The Subpubic Angle Top View Of The Pelvic Cavity Shape MALE FEMALE o Less than a 90 angle Like a "V" shape The space you see inside is more "heart" shaped and small o 90 angle or larger angle Like an "L" shape The space you see inside is more oval/circular in shape and larger Sacrum Shape Sacrum is longer and thinner. Sacrum is shorter and wider. The The Sacrum and coccyx are tilted Sacrum and coccyx are tilted toward the inside of the Pelvic backward away from the Pelvic Cavity and are easily visible from Cavity and are not very visible a top view. 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 Measure with a ruler (mm). The Pubic Bone Width at this location Pubic Bone Width at this location is less than 30mm. is greater than 35mm. **PUBIS SYMPHYSIS** where the two coxal bones meet in the front (ventral) 369 MALE PELVIS FEMALE PELVIS Sacrum longer and thinner Sacrum shorter and wider Sacrum is tilted inward with coccyx pointing into the space 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 Sacrum is tilted backward with coccyx barely pointing into the space Front view of subpubic angle is greater than 900 “L-shaped” Top view of pelvic cavity – space is large and oval or circular shaped Top view of pelvic cavity – space is small and “heart” shaped IF YOU ONLY HAVE ONE COXAL BONE #2 – width of the Pubic Bone here 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 370 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! Table 3 – Characteristics of the Male and Female Humerus MEASUREMENTS OF THE HUMERUS MALE COULD BE MALE OR FEMALE FEMALE Transverse Diameter Of The Head greater than 47 mm 43 to 47 mm less than 43 mm Vertical Diameter Of The Head closer to 48.8 mm 45.8 mm closer to 42.7 mm Width Between Epicondyles closer to 63.9 mm 60.4 mm closer to 56.8 mm Total Length Of The Humerus closer to 339.0 mm 322.5 mm closer to 305.9 mm Vertical Diameter of Head Width Between Epicondyles Dorsal View Of The Humerus 371 Transverse Diameter of Head