1. Forensic Anthropology
Unit 6

2. What is forensic anthropology?
Can be used to determine if bones are human
If so, what age, sex, stature and race was the individual
How long has the person been dead
What is a possible cause and manner of death

3. FORENSIC ANTHROPOLOGISTS
_____________________________________________________________________.
Main Characteristics:
Sex - Determined by examining the skull, pelvis, humerus, and femur
Age and stature (height/build) – Determined by analyzing the development of the teeth, bone growth, cranial suture lines, and the length of specific bones, such as the femur.
Race – Determined by analyzing the skull for characteristics that are common among people of different races.
Damage from a hammer
analyze skeletal remains to determine the identity of a victim as well as his/her life history, cause of death, or other clues about a crime.
Gunshot Wounds

4. What else can we learn from bones?
DNA samples can be collected from bone, teeth, and hair to provide clues to a person’s identity.
Scientists may also be able to gain clues as to a person’s past, recent injuries, or the cause of death based on bone fractures and other signs of trauma.
Healed Fractures

5. Functions and Facts of the Skeletal System
Support and Protection
Body Movement
Blood Cell Formation (bone marrow)- hemopoiesis
Storage of inorganic materials (salts, calcium, potassium)
There are ____________ bones.
Two main divisions:
________________
15 % of your body weight
Stem cells in bone marrow
Storage: fats and minerals that are being recycled
Bone Facts
The smallest bone in the human body is called the stirrup bone, located deep inside the ear. It's only about 3 millimeters long in an adult.
The longest bone in the human is called the femur, or thigh bone. It's the bone in your leg that goes from your hip to your knee. In an average adult, it's about 20 inches long.

6. What are your bones made of?
Now that you know what bones do, let's take a look at what they're made of and their anatomy.
Each bone in your body is made up of three main types of bone material: compact bone, spongy bone, and bone marrow.

9. The inside story
Bones are made of four main kinds of cells: osteoclasts, osteoblasts, osteocytes, and lining cells.
Osteoblasts are responsible for making new bone as your body grows.
Osteocytes are star shaped bone cells most commonly found in compact bone. They are actually old osteoblasts that have stopped making new bone.
Lining cells are very flat bone cells.
Osteoclasts break down and reabsorb existing bone.
Notice that three of these cell type names start with 'osteo.' This is the Greek word for bone. When you see 'osteo' as part of a word, it lets you know that the word has something to do with bones.
Osteoblasts are responsible for making new bone as your body grows. They also rebuild existing bones when they are broken. The second part of the word, 'blast,' comes from a Greek word that means 'growth.' To make new bone, many osteoblasts come together in one spot then begin making a flexible material called osteoid. Minerals are then added to osteoid, making it strong and hard. When osteoblasts are finished making bone, they become either lining cells or osteocytes.
osteocytes
Osteocytes are star shaped bone cells most commonly found in compact bone. They are actually old osteoblasts that have stopped making new bone. As osteoblasts build bone, they pile it up around themselves, then get stuck in the center. At this point, they are called osteocytes. Osteocytes have long, branching arms that connect them to neighboring osteocytes. This lets them exchange minerals and communicate with other cells in the area.
lining cell
Lining cells are very flat bone cells. These cover the outside surface of all bones and are also formed from osteoblasts that have finished creating bone material. These cells play an important role in controlling the movement of molecules in and out of the bone.
osteoclast
Osteoclasts break down and reabsorb existing bone. The second part of the word, 'clast,' comes from the Greek word for 'break,' meaning these cells break down bone material. Osteoclasts are very big and often contain more than one nucleus, which happens when two or more cells get fused together. These cells work as a team with osteoblasts to reshape bones. This might happen for a number of reasons:

11. Determining the Height
Can be calculated from a single bone!
Given that not everyone's arm to leg ratio is exact, height is usually estimated by using more than one bone, if possible
Apart from height, average weight can be calculated based on not only the general size of the bones, but also by evidence of the weight borne by the bones

12. The Human Skeleton

13. I should have known it was going to be one of those days, when I had stepped out of bed and stubbed my (1) PHLANGE on the night stand. While hopping up and down on one (2) METATARSAL and grasping the other, I slipped and fell onto my right shoulder breaking my (3) CLAVICLE. As I crawled on my (4) METACARPALS and (5) PATELLAS to my bed, I felt my (6) CRANIUM begin to ache. I found my phone and let my (7) PHLANGES do the walking as I called my friend to come help me out. My friend answered the phone with a loud scream; my (8) MANDIBLE dropped, I asked what had happened, and he replied that he had been startled by the ringing phone, fell out of bed landed on his (9) COCCYX. Following that while racing to the phone he hit his (10) TIBIA on a stool. I should have known it was going to be one of those days.
1. ____________________________
6. _______________________________
2. ____________________________
7. _______________________________
3. ____________________________
8. ________________________________
4. ____________________________
9. ________________________________
5. ____________________________
10. _______________________________

14. Determining Age
One way we can tell is just by looking at the bones and the wear and tear! This also tells you a lot about the person and their lifestyle.
Arthritis: ______________________________________
Arthritis is therefore the swelling of the joints.
One of the effects of arthritis is to change the shape of the bones at the point where the joints are swollen, as you can see in the images below:
can be broken down to the prefix arthr- = joint, and -itis = inflammation.

15. Using Long Bones to Determine Age
Look at the long bones! Remember the epiphysis??
Epiphyseal Plate: _______________________________________________________________________________________
  X-rays can be used to show comparative age, simply by looking at the end of the long bones, in an area called the epiphysis.  In a child, the area of growth is made of cartilage, and is called the epiphyseal plate.  In the x-ray, it appears as a clear space running approximately parallel to the end of the bone:

16. Can you see the fontanels in the image below
 Can you see the fontanels in the image below?  Note how many places in the infant skeleton are still made of cartilage, which appears blue.  The indicates how much of the skeleton is still developing.
Remember that the total number of bones in the skeleton, 206, is based on an adult skeleton.  The actual number in an infant is much higher!

17. The sutures are, however, useful in terms of determining the approximate age of a skull.  In terms of the sutures, as we grow older, the sutures ultimately completely fill in.  The less filled in, the younger the person.  This does mean that aging has a habit of making us all a bit more hard-headed; this explains a lot about your teachers . . .  We also often tend to lose teeth as we age, and if we really do a bad job flossing, we lose BONE as well, as in the geriatric (elderly) skull below:

18. Determining Sex
There are several things than may, on the surface, be useful to gender determination, but, on upon closer examination, are not very useful. 
For example, females are, on average, shorter than males, but a short skeleton can easily be male.  This is due very simply to the fact that each gender follows a Bell Curve. 
When one graphs the data (as a histogram, or calculated to a bell curve), there is clearly gender overlap.
As such, it is easily possible to have a female at the tall end of the height curve, and a male at the short end of the height curve.  The curves for gender overlap, for the most part, with the peak of each curve slightly off-set.  It is easy to say that the average height is shorter for females than it is for males, but that information is useless when we examine two individual skeletons.

19. The determination of sex by examination of the skeleton is based upon the appearances of:
Long Bones (Humerus…femus…etc) However we now know that determining sex from height isn’t always accurate.
Pelvis
Skull
Sternum
Scapula, metacarpal bones
Using the pelvis is 95% accurate
Using the skull is 90%
Pelvis and Skull is 98%
Long bones at 80%

20. Sexual Dimorphism Differences between male and female include:
Features related to reproductive role
Endocrine system
Physical, psychological and behavioral effects
Evaluating a skeleton for sexual dimorphism is based on
Size difference
Function related differences.

28. Determining Gender using a skull
Landmarks
Female
Male
Chin
Rounded
Square
Mastoid Process (Behind Ear)
Small
Large
External Occipital Protuberance (Back of Skull)
Small (Not Prominent)
Large (Prominent)
General Anatomy
Gracile (i.e., Graceful)
Robust
Forehead
Vertical
Receding (Careful with the comments . . .)
Brow Ridges (Location of Eyebrows)
Slightly Developed
Prominent
Muscle Lines
Orbital Margins (Edge of Eye Socket)
Sharp
Angle of Ascending Ramus (Back Corner of the Jaw)
Obtuse
Close to 90 degrees

33.  There are several ways to more accurately determine the gender of a skeleton.  One of them is by examining the pelvis, which can be identified accurately 95% of the time

34. Determining Race
There are several ways to determine race using a human skull.
We will not be able to go over ALL of the ways, but here are a few.
The bones of a human skull express inherited features from one generation to the next.
Many of these features have developed in response to evolutionary processes, including adaptation to the environment. Since certain anatomical features are found with greater frequency in certain populations, their presence or absence are clues to ancestry.

35. Determining Ethnicity
The palate and palatine suture:  The hard palate is the bony structure at the top of the mouth bordered by the upper teeth.
In American Indians, the palate is elliptical, with the ‘U’ shape angling in at the back teeth.
In blacks, the palate is hyperbolic—a perfect ‘U’ shape with straight lines.
And in whites, the palate is parabolic with the ends of the ‘U’ flaring outwards.

36. The transverse palatine suture that horizontally transects the palate also varies by race: It is straight in American Indians, curved in blacks, and a jagged line in whites.

37. Individuals with European ancestry tend to have straight facial profiles and narrower faces with projecting, sharply angled nasal bones.
Individuals with American Indian ancestry have proportionately wider faces and shorter, broader cranial vaults.
Individuals with sub-Saharan African ancestry generally show greater facial projection in the area of the mouth, wider distance between the eyes, and a wider nasal cavity.

38. Gun Shot Wounds
Common cause of death in accidents, suicides & homicides.
Wounds vary due to:
Distance of gun
Angle of entry
Caliber & velocity

39. Entrance and Exit Wounds
This is a typical entrance wound, showing inward beveling of the skull’s outer surface, caused by a 22 caliber bullet
As the bullet enters it tumbles, exposing more surface area to the tissue, resulting in greater damage and a larger exit wound.
This shows an exit wound, which is typically greater in size than the entrance wound.
Small caliber ammunition may fragment resulting in smaller exit wounds

40. Gun Proximity
The proximity of the gun causes different patterns on the flesh:
This is a STELLATE pattern, caused by a gun pressed to the body
When a gun is less than 6” away a compact hole results, with stippling and charring around the edges. Tissues will be bright red.

41. Gun Proximity
TATTOOING results when a gun is fired from a distance of 6” to 2’. Hemorrhaging of the surrounding skin is caused by particles embedded in the skin.
Hemorrhaging is an escape of blood from a ruptured blood vessel, especially when profuse.
ABRASION COLLARS, or blue/black bruising around the entry wound, are produced when the gun is more than 2’ away

42. Knife Wounds Also known as sharp force injury or penetration wounds.
3 types
Stab
Cut
Chop

43. Stab Wounds Greater depth than width.
Often distorted due to movement of the victim
Occasionally can distinguish weapon type, blade length or hilt pattern.

44. Cut Wounds Caused by drawing a sharp instrument across the skin
Rarely fatal
Associated with:
Suicide – hesitation marks
Defensive – cuts on hands, forearms and wrists
Accidental – usually on hands
Homicidal – typically on the neck, L-R path in a right handed attacker

45. Chop Wounds Made by axes and cleavers Deep and wedge shaped.
May mark underlying bones.
Usually homicidal or accidental

46. Blunt Force Trauma Body makes contact with a hard dull object.
Common causes include:
Car accident
Sporting accident
Assault
Trips and falls

47. Abrasions Only superficial skin removed.
Sliding – friction burns, rope rash
Stamp – crushing by blunt object, ex baseball bat
Patterned – leaves imprint of clothing or object, ex chain marks
                               

48. Bruising & Contusions
Leaking blood collects in a pocket beneath the skin – hematoma.
Hema – blood
Toma – bleeding from a body…bleeding

49. Broken Bones
                                                                                                                                                             

50. Indirect Fractures Angulation – bone bent to breaking point
Rotational – spiral fracture along long axis, ex yanking child by arm or leg
Compression – T or Y shape. Bone is pushed or compressed.
Combination

51. Bite Marks Murder Child abuse Spousal abuse Torture Rape
May be able to swab for DNA.
May be able to match to dental impressions
Used in Ted Bundy case

52. Head Injuries Often accidental
Death usually due to intracranial bleeding
Epidural – between dura and skull(accidents,falls)
Subdural – between dura and brain(BFT)
Intracerebral – within the brain(aneurism,stroke)

53. Skull Fractures Simple Linear – low impact falls
Circular – blow with a circular object
Depression – section pushed inwards. Impact site is COUP. If brain hits inside of skull at another site this is the CONTRECOUP
Stellate – localized blow

54. Electrocution
Low voltage – causes arrhythmia. Leaves no external burns.
High voltage – burns inside and out. Paralyzes respiratory center of brain leading to asphyxiation.

55. Electrocution Charring of skin at entry or grounding points
Localized rigor mortis due to rapid consumption of ATP
Lichtenburg Figures – associated with lightning strikes

56. The End…