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Human Remains
Using the Forensic Science Textbook by Funkhouser read Chapter 12Human Remains.
Complete the Following:
1. Activity on page 274---Identifying Bones
2. Activity on page 275---Estimating Height,
3. Activity on page 278—Determining Sex Using the Os Pubis
4. Activity on page 279---Determining Sex using Skull features
5. Activity on page p 282 Determining Age Using the Epiphyses
6. Draw a diagram that illustrates the difference between male and female
pubic bone. Label pubic arch, pubic body, ventral arch( in female)
Objectives- pg. 269.
After reading this chapter, you will understand:
1. How anthropologists can use bones to determine whether remains are
human; to determine the sex, age, and sometimes race of an
individual; to estimate the height; and to determine when the death
may have occurred.
You are responsible for knowing:
1. How to distinguish between a male and a female skeleton.
2. Give the age range after examining unknown remains
3. Describe the differences in skull features among the three major racial
categories
4. Estimate the height by measuring the long bones
5. Describe the livor mortis, rigor mortis, and algor mortis
6. Anything else I decide to add.
Quiz over pages 269-274
Human Remains--Notes
Forensic Science Textbook by Funkhouser read Chapter 12-Human
Remains.
A pathologist or medical examiner usually determines the time of death.
This is done most accurately if the body is found within the first 24 hours
of death. One of many ways to help determine the time of death is
indicators such as:
Algor mortis
Livor mortis
Rigor mortis
Algor mortis refers to the cooling rate of the body after death. The body
cools at a rate of approximately 1-11/2 oF per hour until it reaches the
environmental temperature
Livor mortis refers to the pooling of blood in the body after the heart
stops, caused by gravity. It will appear on the skin as a purplish red
discoloration and can indicate the position of the body at the time of
death. There is no livor mortis in the areas that touch the ground or that
are constricted by other objects because the capillaries are compressed,
preventing blood pooling. Livor mortis begins within 30 minutes of
death and is most evident after 12 hours after death. After that, the
discoloration of livor mortis will not move regardless of how the body is
disturbed. This can be useful in determining whether a body has been
moved after death
Rigor mortis refers to the rigidity of the skeletal muscles after death. As
soon as a person dies, the muscles relax, the ATP (adenosine
triphosphate) in the muscles begin to break down, fluid concentrations
change, and the muscles become rigid. Because rigor mortis begins in
the smaller muscles, it is seen first in the face, neck, and jaw. The
noticeable stiffness of rigor mortis occurs within 2 or 3 hours after death
and is gone within approximately 30 hours, leaving the body limp. The
effects of rigor begin to disappear in the same order as they began, the
small muscles becoming limp first, then the larger muscles of the trunk,
arms, and legs. Rigor mortis is also affected by the environmental
conditions such as temperature, dehydration, condition of muscles, and
their use prior to death.
Forensic Anthropology: Skeletal Remains
Forensic anthropology is a type of applied physical anthropology that
specializes in the human skeletal system for purposes of identifying
unknown remains.
Forensic Anthropologist study skeletons whose identities and circumstances
of death are unknown or questionable.
HUMAN vs. ANIMAL BONES
Osteology-the study of bones
Humans and animals have different skeletal structures, different bones, and
different shaped bones. The human bone can be distinguished from animal
bone through microscopic examination of the cellular structures. Bones
have holes or osteons in them to carry their blood supply. Microscopic
examination shows that in animals the osteons for a regular pattern, but in
humans the osteons are arranged in a more chaotic pattern.
THE SKELETON
Human adult skeleton has 206 bones
Ossification sites –sites where growth takes place and found on many
bones.
Vital functions of skeleton
 provides structure and rigidity for the body
 Shelters and protects soft tissue and internal organs
 Provides sites for the attachment of muscles, tendons, and ligaments
that allow the body to move.
 Stores minerals and houses sites that produce red blood cell
Skull – surrounds and protects the brain
Sternum and rib cage- encase the heart and lungs
Tendons and ligaments are structurally similar but function differently.
Muscles are connected to the bones by tendons. Bones are connected to
each other or to joints with ligaments.
Joints-points where a muscle is connected to two different bones and
contracts to pull them together.
Marrow-produces red blood cells and cells of the immune system.
Bones serve as a storage area for minerals such as calcium and phosphate
Bone tissue can also clean the body by removing heavy metals and other
foreign elements from the blood.
Bones can be classified as:
1. long—are longer than they are wide; they include bones in the arms,
legs, hands, and feet.
2. short-are approximately as long as they are wide; they are found in the
wrist and ankle.
3. flat-are flat and enclose soft organs; they include most bones in the
skull, the scapula, sternum, hip bone, and rigs
4. irregular-are irregularly shaped; they include the vertebrae and some
of the bones in the skull.
STATURE-ESTIMATING HEIGHT USING LONG BONES
A PERSON’S STATURE CAN BE ESTIMATED BY EXAMINING ONE
OR MORE OF THE LONG BONES. The long bones used for this are the
femur, tibia, humerus, and radius. Men and women have different
proportions of long bones to total height, so separate formulas have been
developed. If complete long bones are available, the following formulas
may be used to estimate height within a range of + 7.5 cm.
To estimate the height of a female (cm)
H=femur length X 2.21 + 61.41
H=tibia length X 2.53 + 72.57
H=humerus length X 3.14 + 64.97
H=radius length X 3.87 + 73.50
To estimate the height of a male (cm)
H=femur length X 2.23 + 69.08
H=tibia length X 2.39 + 81.68
H=humerus length X 2.97 + 73.57
H=radius length X 3.65 + 80.40
SEX DETERMINATION
 The os pubis, sacrum and ilium of the pelvis are bones that have the
most obvious differences between men and women. The shape of the
skull mandible, and the size of the occipital proturbance (bump) at
the back of the skull to determine male or female traits.
 Men tend to have larger bones than females.
 Males have larger areas for muscle attachment.
 The sacrum is straighter in females & more curved in males.
 The space in the middle of the pelvic bone is larger in women to make
birthing easier.
 To make the surest determination of sex, one can compare 3 basic
characteristics of the os pubis
o 1. the width of the pubic arch-larger angle in females than
males
o 2. the width of the pubic body-narrower in males than females
o 3. the existence of the well defined ventral arch (bony ridge on
the lower side of the female pubic bone.)---males do not have a
ventral arch.
The ventral arch does not usually appear in its easily recognizable form until
a woman is in her mid-20’s. A precursor arc, (a small bony line) first
appears around the age of 14. p277 fig 2
Dorsal-upper side
Ventral-under side
DIFFERENCES IN SKULL FEATURES
Determine Age with a skull
 Epiphyses-growth plates found at the end of the long bones. They
form in adolescence and fuse to the bone in early adulthood. Function
is to allow for growth. Diaphysis-Shaft of bone. Makes up most of
the long bones’ length.
 Iliac crest-found at the top of the hip bone
 Clavicle-also known as the collarbone. Its medial ends meet in the
center of the body.
 Closure of cranial sutures
 Teeth erupting
The epiphyses fuse to the bone during adolescence and can be examined in 4
stages
1. Stage 1- non union with no epiphysis (there is no growth plate
yet.)
2. Stage 2- Nonunion with separate epiphysis (the growth plate is
formed but not attached)
3. Stage 3- Partial union of the epiphysis (growth plate is
beginning to attach to the bone.)
4. Stage 4- Complete union of the epiphysis (growth plate is
completely attached and smooth.)
These stages happen in different ages in different bones and in
males and females.
Table 1- General age determination using epiphyseal union of the medial
clavicle.
Stage of Union
Nonunion without
separate epiphysis
Nonunion with separate
epiphysis
Partial union
Complete union
Male
21 or younger
Female
20 or younger
16-21
17-20
17-30
21 or older
17-33
20 or older
Table 2- General age determinations using epiphyseal union of the iliac
crest
Stage of Union
Nonunion without
separate epiphysis
Nonunion with separate
epiphysis
Partial union
Complete union
Male
16 or younger
Female
11 or younger
13-19
14-15
14-23
17 or older
14-23
18 or older
Estimating age based on Cranial Sutures
 Sutures-immovable joints where bones are joined together. They are
visible as seams on the surface.
 Sagittal suture-located along the top of the skull, dividing the right
from the left and runs from the top of the skull to the middle of the
back of the skull.
 Coronal suture-runs from the temporal area on one side over the top
of the skull to the other side.
 Lambodial suture-located on the back of the skull.
If the sagittal suture is completely closed (not visible at any point)
Male – the individual is 26 yrs. Of age or older
Female-the individual is 29 yrs. Of age or older
If the sagittal suture is completely open (visible at all points)
Male – the individual is younger than 32 yrs. of age.
Female- the individual is younger than 35 yrs. of age.
Looking at these 2 criteria together, it could be said that the sagittal suture is
not likely to be open if a male is older than 32 and not closed if younger than
26. For a female, the suture is not likely to be open after 29 and not closed if
younger than 35.
If the skull shows complete closure of all 3 major sutures (no visible lines):
Male-the individual is older than 35.
Female-the individual is older than 50.
Determine the age of the skulls provided based on cranial sutures. P 285
Determining age using the os pubis
The closing of the epiphysis is a good method to determine age in younger
skeletal remains. Once the epiphyses are closed, forensic anthropologists
observe degenerative changes to determine age. One of the best areas to
determine age in adults is from the pubic symphysis, which is the area where
the 2 hip bones come together in front. As a person ages, the 2 bones may
rub together, producing changes or wear patterns.
The symphyseal face of the pubic bone undergoes a regular metamorphosis,
or change, from puberty onward. The pattern on the symphysis goes from
being in regular rows or furrows in younger individuals, to smooth with an
oval surface, to a breakdown of the bone in older individuals.
Determination of Race
Three major anthropological racial groups based on observable skeletal
features
1. Caucasoid-includes people of European, Middle Eastern, and East
Indian descent.
2. Negroid-includes people of African, Aborigne and Melanesian
descent
3. Mongoloids-include people of Asian, Native American, and
Polynesian descent
Major differences in skull features
1. Caucasoids-have a long, narrow nasal aperture; triangular palate; oval
orbits; narrow zygomatic arches; and narrow mandibles.
2. Negroids-have a wide nasal aperture; a rectangular palate; square
orbits, and a more pronounced zygomatic arches. The long bones are
longer and have less curvature and a greater density.
3. Mongoloids-have a more rounded nasal aperture; a parabolic
palate; rounded orbits, wide zygomatic arches, and a more
pointed mandibles.
p 286
FACIAL RECONSTRUCTION
Facial reconstruction uses standard tissue thickness and facial muscles to
build a new face on a skull.
Steps in facial reconstruction include:
 Establish gender, age and if possible-race.
 Glue tissue markers to landmarks directly on the skull for tissue
thickness
 Mark muscle insertion points
 Select data set to use for the particular skull, and mount markers for
the exact thickness of tissue.
 Mount eyes in the sockets, centered and at the proper depth.
 Apply clay to the skull following its contours, using the depth of the
tissue markers and muscle insertion points.
 Make measurements to determine the nose thickness and length and
the mouth thickness and width.
 Cover the skull with layers of skin and add details of the face
Lab Activity “Talking Bones”
Step 1 Determining the Number of Individuals in a Co-Mingled Remains
Step 2-Determine the Relative Age, Trauma, and Presence of Disease
Step 3-Record all information regarding each bone on the Skeleton
Inventory Form for all recovered bones and bone fragments
Step 4-Determining Ancestry
Step 5-Determining Gender
Step 6-Determining Stature
Step 7 Summary Findings and Site drawing