Boning-UP
It is possible to use skeletal
bones to determine and height and sex of an individual. In this exercise we
will be using a combination of hands-on bone measuring as well as computer X-rays.
SEX: The very best bones for this interpretation are those of the pelvis, specifically
the pubic bones. The two pubic bones form an angle -- the sub-pubic angle (Shown
as 1-2-3) -- that the newborn uses for their entry into the world. When this
angle measures 100 degrees or more the specimen is that of a female. Less means
a male. This cannot be done on the bones of a preadolescent, females do not
show the skeletal evidence of their sex until they pass the puberty stage
.
The diagram on the left shows just how to measure this angle with a protractor. Just be sure to double the figure you get as you are measuring one half. If you a real bone skeleton or a plastic replica, some members of the class can be doing this protractor measurement while other class members are analyzing this angle on several X-Rays that they are bring up on the computer.
Height
The long bones relate to one's height, those of the lower limbs, femur, tibia and fibula being the best. There are both racial and sexual differences so that one needs to know both to enter the regression formulas after measuring the length of the available bones. The stature (height) table that is included is from Trotter and Gleser.
Hands-On Results Sheet
The upright skeleton is from a Black and has a sub-pubic arch angle of _________ and is a __________, while the White skeleton on the table has a sub-pubic arch angle of _________ and is a __________.
Odd groups go to the upright skeleton - Even to the horizontal skeleton
Group A - Measure femur and radius on your skeleton
Group B - Measure tibia and ulna on your skeleton
Group C - Measure fibula and humerus on your skeleton
Put all your work in the section below: Example: If you found the radius on the skeleton to be 25 cm and the bone had come a Mexican male. The height would be 25 cm. X 3.55 for a total of 88.75 cm plus 80.71 cm for a total height of 169.46 cm. with an accuracy of plus or minus 4.04 cm.
Actual height of skeleton _______________ cm.
Show all work and label all answers
Bone 1 (______________) Length:_______________ cm.
Calculations
Bone 2 (______________) Length:_______________ cm.
Calculations
Take the unknown bone you are given, identify it and calculate the height of the Black, male owner. Again show all work and label all answers.
Unknown Bone (______________) Length:_______________ cm.
Calculations
