quiz 3 bl
forensic facial reconstruction- 3 main methods
2-dimensional 3-dimensional superimposition
age determination- cranial sutures: there are _______ major cranial sutures that appear as distinct lines in youth and gradually close from inside out
3 major cranial sutures sagittal coronal lambodial
skeletal age can be determined by looking at the follwing:
sutures of the skull teeth ribs vertebrae growth areas of the long bones: epiphyses
facial reconstruction
-A method used for attempting to identify the remains of an unknown person using the cranium -Methods rely on artistry, in depth understanding of human anatomy, and application of advanced imaging technology
bitemark analysis on trial
-Bite mark or dental impressions of skin, tissue or other materials such as food -In theory uniqueness of teeth (number, spacing, surface characteristics etc) contribute to individual bit patterns -Has been in the US since 1954
age determination using long bones
-Bone growth can be used for determining an age range of humans Bones have three distinct sections 1. Diaphysis or shaft 2. Metaphysis or flared end of shaft 3. Epiphysis or end plate 4. The growth plate is located between the epiphysis and metaphysis While growth of bone is continuing, the growth plate can expand as new layers of cartilage are laid down. As we age, cartilage is replaced by bone --carilage is dark on xray
stature
-Determination of stature is generally the final demographic characteristic in osteological analysis -It can be determined by rearticulating the skeleton -However, this requires a complete set of remains relevant to height -Generally a disarticulated, partial skeleton is discovered
bite mark anaylsis
-Lack of scientific evidence 1.Establishing the uniqueness of bite marks to each individual 2.That teeth can be matched to bite marks on human skin There is anecdotal evidence that teeth are one of a kind like fingerprint Recognition of bite marks have also not been established (is it even a bite mark?) The American dental assoc and FBI no longer recognize bite mark evidence as standalone evidence -The practice, however is still admissible in court in the US -If it is coupled with DNA, blood evidence, etc it may be able to be used... ITS NOT USED STANDALONE
differences in skulls
-Males have heavier brow ridge ...More pronounced -Orbits are smaller in males -Males have heavy mandible -Female skulls are smaller with rounder mandibles
fully method
-Measurements include: -skull height -vertebrae height -lengths of femur and tibia -Ankle height -The values are summed -If the bone has dried significantly, increase each value by 1.5% -Use tables with soft tissue correction factors -The total is an estimate of height
ancestry
-One of the early functions of the discipline was assessment of the genetic background of individuals from skeleton remains -This is most commonly referred to as race determination -Race is difficult to determine from most skeletal remains, especially since pure races are becoming uncommon -The latter is a reflection of changes in societal norms, which can be used as a means to 'date' a skeleton
epiphyseal fusion
-The figures below are of the Epiphyses of the femur or thigh bone (the ball end of the joint, joined by a layer of cartilage). -The lines in the illustrated Image 1 show the lines or layers of cartilage between the bone and the epiphyses. The lines are very clear on the bone when a person, either male or female is not out of puberty. -In Image 2, you see no visible lines. This person is out of puberty. The epiphyses have fully joined when a person reaches adulthood, closing off the ability to grow taller or in the case of the arms, to grow longer.
long limb bones
-This is the most common method used -Measurements of long bones of arms and legs, minus feet and hands -Use of calipers or bone boards -Values plugged into regression formulae to estimate stature
age determination epiphysis
-an epiphysis is the growth plate area at the end of the long bone. these areas close or fuse at different ages - for females, fusion is complete between 18-20 years - for males fusion is complete betweem 17-21 years
age determination
-infant has 300 bones -some fuse together at predictable rates -adult human has 206 bones -ossification-process whereby cartilage changes into bone-results in bones fusing -epiphysis and diaphysis fuse together -age 14-humerus -age 21-pelvis
the main aspects of forensic odontology (forensic denistry) include
1. Dental identification 2. Age estimation 3. Sex determination 4. Role in mass disasters 5. Role in domestic violence, abuse and neglect 6. Identification of bite marks 7. Blood group determination 8. Recent advances: DNA typing, computer assisted dental identification, , digital analysis of bite marks, digital autopsy
race
An experienced forensic anthropologist can generally place skulls into one of three (four) groups: -Caucasian—European, Middle Eastern, and Indian descent -Negroid—African, Aborigine, and Melanesian descent -Mongoloid—Asian, Native American and Polynesian descent
other features of the skull
Brow ridges= -large and pronounced vs nearly flat Vault sutures= -simple vs complex Palate= -rectangular, triangular, parabolic
process in Race assessments:
Can only be determined using adult skeletons The skull provides the most reliable markers When remains display characteristics attributed to two groups, the ancestry should be assigned to how the person was perceived in life.
Most accurate estimations from:
Cranial sutures: the three major cranial sutures appear as distinct lines in youth and gradually close from the inside out (BROAD CHARACTERIZATION) Epiphyses or growth plates (BROAD CHARACTERIZATION) Teeth Pubic symphysis --Investigators always use an age range because of the variation in people and how they age. The investigator does not want to eliminate any possibilities for identification.
determination of gender: cranium
Crests and ridges more pronounced in males (A, B, C) Chin significantly more square in males (E) Mastoid process wide and robust in males Forehead slopes more in males (F)
more applications of anthropology
Forensic experts may be called upon to give information on the life and death of humans and animals in unique circumstances, including: -Mass Murder (Oklahoma bombing, plane crashes, World Trade) -Earlier man (mummies, Iceman, Lindow man) -Historical Significance (Holocaust, uncertain death of famous people) -Prehistoric Animals (Dinosaurs)
long limb bone method: Formulae are specific to=
Gender Age Race
goals facial reconstruction
Goals: 1) Circumstantial identification: is achieved when the reconstruction fits the biological profile of the remains 2) Positive identification: occurs when a unique set of biological characteristics of an individual are matched with the remains
gender difference:fingers
In males the index finger is sometimes shorter than the third finger. In females, the first finger is sometimes longer than the third finger. This is not often used as an indicator of gender as there are many exceptions.
story of impressive faical reconstruction
John List killed his entire family, moved to a new town and assumed a new identity. Seventeen years later, Frank Bender reconstructed what he believed List would look like. It was shown on America's Most Wanted, and he was turned in by the viewers almost immediately. . . looking very much like the reconstruction.
signs of wearing and antemortem injury
Occupational stress wears bones at joints Surgeries or healed wounds aid in identification
age deterimination using cranial sutures=
One method for aging human skeletal remains is to use cranial sutures -there are 17 unique cranial sutures associated with the human skull -whether they are open or fused is generally age dependent Generally sutures are given a numerical score from 0-3. 0 = suture is open, with no evidence of ectocranial closure 1 = minimal closure of suture 2 = significant closure of suture 3 = complete fusion of suture (obliterated suture) The vault constitutes sutures 1-7 Lateral-anterior sutures 6-10
determination of gender
Pelvis is best bone to make distinction. Why? females have wider subpubic angle females have a sciatic notch > 90° females have a broad pelvic inlet pubic symphsis changes/ -A change to the surface of certain bones, bone wearing or erosion, can also contribute to age determination especially in adults. -Standards of bone erosion are compared to bones that undergo common wear such as the pubic symphysis. -The pubic symphysis goes from having a rough, rugged surface to a smooth area over time. -The downside of this is that FA are measuring the degradation of bones which is more variable to error due to other factors.
superimposition=
Relies on recent antemortem photographs and the skull overlay
key features of the skull
Shape of eye sockets= -oval, rectangular, or square, size in relation to skull Shape of nasal aperture= -narrow, flared, round, inside flat or with sharp sill Jaw= -prognathous or under eye sockets Shape of skull= -rounded, domed, squared
fetal development
Size of the skull, size of sutures, and degree of ossification can be used for age determination of fetal remains --Calcification is not complete yet and that is clear by large sutures and cartilage present
odontology and identification
Teeth are often used for body identification because: -They are the hardest substances in the body -They are unique to the individual -X-rays are a good record of teeth Sometimes the only thing left of the body, and in US there are generally good records of their teeth on record
estimation of height
The height of a person can be calculated by using the length of certain long bones, including the femur, tibia, humerus, and radius. Below are the equations to determine average measurements for both male and female. (All measurements are in centimeters) Male Female femur x 2.23 + 69.08 femur x 2.21 +61.41 tibia x 2.39 + 81.68 tibia x 2.53 + 72.57 humerus x 2.97 + 73.57 humerus x 3.14 + 64.97 radius x 3.65 + 80.40 radius x 3.87 + 73.50 FIND HEIGHT LAST BC WE NEED KNOW GENDER FIRST^^
odontology
The identity of an individual can be determined by comparing a person's teeth to their dental records. Unusual features including the number and types of teeth and fillings, the spacing of the teeth, and/or special dental work (bridges, false teeth, root canals) help to make a positive identification.
another gender difference: The ribcage and shoulders of males are generally ________________. In addition, about one person in twenty has an extra rib. This is more common in __________.
The ribcage and shoulders of males are generally _____wider and larger than that of females______. In addition, about one person in twenty has an extra rib. This is more common in_____males than in females_____. THIS IS NOT AS ACCURATE AS PELVIS
3-dimensional=
Uses sculpting from cranial remains or use of 3-D computer software
2-dimensional=
Uses tissue depth markers on the skull at various anthropological landmarks, which are then used by an artist to create a likeness
steps in 3d faical reconstruction
With a skull: -Establish age, sex and race -Plot landmarks for tissue thickness -Plot origin and insertion points for muscles -Plot landmarks for facial features -Select a dataset and mount markers for tissue thickness -Mount the eyes -Model muscles on skull -Add fatty tissue around eyes and lacrimal glands -Add eyelids -Add the nose -Add the parotid gland -Add the ears -Cover all with layers of skin -Detail the face
the body farm
bill bass The nickname of a two and a half acre research facility in Tennessee developed in 1980 by Bill Bass where bodies are placed in various conditions and allowed to decompose. Its main purpose is to observe and understand the processes and timetable of postmortem decay. Over the years it has helped to improve the ability to determine "time since death" in murder cases. Hic locus est ubi mortui viveuntes docent. This is the place where the dead teach the living. There are now six 'body farms' in the United States that rely on human cadavers for various decomposition studies The Original: University of Tennessee-Knoxville Western Carolina University (Cullowhee, NC) Texas State University (San Marcos, TX) Sam Houston State University (Southeastern TX) Southern Illinois University (Carbondale, IL) Colorado Mesa University
osteology
everything just discussed falls under this -Is the scientific study of bones (206 in human body). This is considered a specialization within anthropology. An expert knows far more than just how to identify bones
Caucasoids=
have a long, narrow nasal aperture, a triangular palate, oval orbits, narrow zygomatic arches and narrow mandibles.
Mongoloids=
have a more rounded nasal aperture, a parabolic palate, rounded orbits, wide zygomatic arches and more pointed mandibles.
Australoids=
have a narrow nasal aperture that flares at bottom, bridge of nose is flat, large teeth by comparison to other races, elongate skull that appears oval from side, ridge brows large and pronounced, eye orbits large in relation to face
Negroids=
have a wide nasal aperture, a rectangular palate, square orbits, and more pronounced zygomatic arches. The long bones are longer, have less curvature and greater density.
forensic anthropology
is a type of applied anthropology that specializes in the changes and variations in the human skeleton for the purpose of legal inquiry -Often work with military, FBI and CIA to identify victim's remains in advanced stages of decay -In practical terms, this means post bloat to dry stages -Also individual identification when person has been burned, mutilated, or otherwise unrecognizable (times when forensic medicine offers little utility) -Modern FA used to identify the living from surveillance images, based on footprints/gate, or biometric features based on understanding skeleton
age determination: use of teeth
pic
forensic anthropologists are trained physical anthropologists who apply their expertise to solve crime of homicides by identifying:
race sex age stature ethnicity culture--- in some cases religion--- in some cases caste-- in some cases
age determination- cranial sutures: sagittal suture completely closed= sagittal suture completely open= complete closure of all 3 major sutures=
sagittal suture completely closed= male-26 or older female-29 or older sagittal suture completely open= male-less than 32 female- less than 35 complete closure of all 3 major sutures= male- over 35 female- over 50
skeletal age=
the estimated age at which a person died.
methods of determining stature=
usually in the order of most common: Measurement of long limb bones Fully Method Measurement using partial long limb bones
primary methods for forensic anthropologists
usually in this order: determination of age determination of gender determination of race determination of stature
Function of bones:
§Provides structure and rigidity §Protects soft tissue and organs §Serves as an attachment for muscles §Produces blood cells §Serves as a storage area for minerals §Can detoxify the body by removing heavy metals and other foreign elements from the blood
