Spark 3rd Exam Flashcards
Why should more caution be taken when using the skull to provide sex determination rather than the pelvis?
The skull has a 96% with pelvis while you get a 92% with skull accuracy
Differentiate between the male and female adult human skull using the cranial morphology scoring technique described in Buikstra and Ubelaker’s Standards for Data Collection from Human Skeletal Remains (1994).
Differentiate between male and female adult humans using metric methods, as described in lectures.
This is used to measure the, Humeral head maximum diameter, Femoral head maximum diameter, Humeral epicondylar width:
< 41.5 mm = female
41.5 - 43.5 mm = ?female
43.5 - 44.5 mm = unknown
44.5 - 45.5 mm = ?male
> 45.5 mm = male
Why is it generally ill-advised to attempt to estimate biological sex in subadult skeletal remains?
Prepubertal bodies exhibit little sexual dimorphism
Despite reservation, describe one way to differentiate between male and female subadult humans using the greater sciatic notch, as described in lectures.
Greater sciatic notch angle is greater than 90 degrees in female juveniles
Broader greater sciatic notch in females
Why are DNA analyses not the most common way to determine the biological sex of human skeletal remains?
It is difficult and expensive.
List and describe the two broad age categories in humans.
Adults and subadults
What difficulties complicate age at death determinations?
Biological age (physiological age) and chronological age (time since birth) are inter-related, but biological age is affected by activity, diet, disease so , age estimation in subadults more precise than adults
List and describe the age classes as proposed by Buikstra and Ubelaker (1994)
Fetus (before birth)
Infant (0–3 years)
Child (3–12 y)
Adolescent (12–20 y)
Young adult (20–35 y)
Middle adult (35–50 y)
Mature adult (50+ y)
How are age-at-death determinations typically assessed in fetal remains?
Reference tables, regression equations are used to determine age of death
Describe the age determination method described by Adalian et al. (2002)
Adalian used the equation 0.434 × femoral length (in mm) + 6.93 which gives us the death in weeks
Describe typical age-at-death determination methods in subadult remains using dental developmental indicators.
compare developmental stage of teeth with reference charts
Formation occurs from crown to root
Tooth eruption rates are more useful than tooth formation stages
If no Stage H development for third molar, then under 18 years old
List common human fontanelles
Anterior, Posterior, Sagittal, Mastoid, Sphenoid
When does sagittal fontanelle obliteration occur?
When birth
By what age are 38% of fontanelles closed?
By 12 months
By what age are 96% of fontanelles closed?
By 24 months
Describe typical age-at-death determination methods in subadult remains using endochondral ossification and epiphyseal fusion.
For endochondral ossification we can tell a subadults age by how much the cartilage as ossified (closed). As for epiphyseal fusion anthropologist can see how old a child is by how much the epiphysis has fused with the diaphysis.
Define epiphyseal fusion
union of primary and secondary ossification centers at a growth plate
Summarize milestones occurring during various subadult age classes
Infancy:
* Birth: primary ossification centers
0-2 years:
* Deciduous dental formation and eruption
1-2 years:
* Fontanelles close
4-6 years:
* Formation of permanent teeth
7-12 years:
* Eruption of permanent teeth
* Secondary ossification centers
* Adolescence
* Eruption of teeth and epiphyseal
fusion
List typical age-at-death determination methods in adult remains
- Cranial suture closure
- Sternal rib-end morphology
- Auricular surface morphology
- Pubic symphysis morphology
Describe the Suchey-Brooks system of age determination, including advantages and limitations of the method
Observable pubic symphysis changes classified into six phases for each sex
Young: billowing
Middle: distinct rim
Mature: degeneration
Advantages:
Casts available for visualization
Multiple confidence intervals
Limitations:
Overlapping stages
Less accurate for +40 yrs
Describe the Lovejoy auricular surface morphology method of age determination, including advantages and limitations of the method
Observable auricular surface
changes classified into eight phases
Young: fine grained surface; billowing
Middle: coarse surface; microporosity
Mature: dense, disorganized surface;
macroporosity
Advantage: auricular surface is
more likely to be preserved than
pubic symphysis
Limitation: more difficult
Describe the sternal rib ends method of age determination
Age-related changes at the sternal end of the right fourth rib
Describe the cranial suture closure method of age determination
Assess degree of fusion for vault and lateral-anterior cranial suture segments
As the skull gets older the more the line disappears
List the three stages of forensic case analysis
What is it?
How old is it?
What is the taphonomic context?
What are taphonomic research facilities?
Outdoor labs using donated human cadavers to study decomposition in a variety of conditions
What benefits do taphonomic research facilities provide?
- Interdisciplinary, research-driven,
longitudinal studies across
different geographic areas - University-level research which
expands disciplinary knowledge - Training opportunities for
anthropologists, law
enforcement, death investigators
Describe the components of the Forensic Anthropology Center at the University of Tennessee
- Anthropology Research Facility (ARF)
Dr. William Bass established the world’s first
“Body Farm” in 1980 - Bass Donated Skeletal Collection (DSC)
Largest collection of contemporary Americans
Body donation → Intake → ARF → DSC - Forensic Anthropology Data Bank (FDB)
Contains demographic information, metric data,
pathological conditions
Database is used by the FORDISC ancestry estimation software program
Define the following terms: decomposition, autolysis, putrefaction
Decomposition - body begins to decay
Autolysis – postmortem breakdown of cellular material via ‘self-digestion’ by enzymes
Putrefaction – anaerobic breakdown of macromolecules by symbiotic bacteria
Describe postmortem changes beginning 0-2 hours after death
- Pallor mortis – paleness
- Bowel release
- Tâche noire de la sclérotique – dark discoloration of the eye
Describe postmortem changes beginning 1-4 hours after death
- Hypostasis– gravitational pooling of
blood (AKA livor mortis) - Algor mortis – body temperature
equilibration - Rigor mortis – muscle stiffness
The stages of decomposition are based on which two factors?
based on gross changes and arthropod activity
Provide caveats to using a staging system of decomposition
- Multiple stage systems
exist, with slight variations - Certain changes could
appear earlier, later, or
never during decomposition
Describe the lifecycle of the typical blow fly
It begins with an egg, then turns into the 1st instar, 2nd instar, and 3rd instar, into pupa and finally into an adult fly
List and describe the stages of decomposition, as discussed in lectures
Fresh: Flies attracted to the body
Active Decay: Discoloration, Bloat, Odor, Maggots
Advanced Decay: Beginning skeletonization, Extensive insect activity
Skeletonization: Greater than 50% exposure, Beetles
Define the following terms: skin slippage, marbling, bloat, fluid purge, cadaver decomposition island, desiccation
Skin slippage: the outer layers of the skin start to separate or slide off from the underlying tissue
Marbling: web-like lines when the body dies
Bloat: the body begins to fill up with carbon dioxide and methane
Fluid purge: leakage of fluids due to the breakdown of tissues and the buildup of gases
Cadaver Decomposition: the area around a decomposing body where changes occur due to the breakdown of the body
Desiccation: When a body loses its moisture and dries out
Define the following terms: arrested decay, mummification, saponification
Arrested decay: stopping or slowing down decomposition
Mummification: aridity (complete loss of moisture) preserves soft tissue
Saponification: anaerobic (no oxygen) and alkaline (basic pH)
environments convert body fat to adipocere (waxy, soap-like
substance)
What is a sokushinbutsu?
practice of Buddhist monks deliberately mummifying themselves while still alive
Describe the process of becoming a sokushinbutsu
Monks have a diet, only bark, seeds, and nuts. Then they drink tea from the sap of a tree. Then the monk is put into a coffin underground with a bell that they ring to make sure they’re still alive. Once the bell stops ringing then other monks check to see if their mummified or it decomposed.
Provide historical examples of individuals whose bodies exhibit arrested decay
Chinchorro mummy, Tollund Man, Soap Lady, Otzi, the Iceman
What is kusôzu?
They are images of a decaying corpse. It portrays the decomposition of a human body in a series of stages, usually in graphic and detailed ways
A forensic anthropologist has been provided of a set of human skeletal remains. What information about the taphonomic history of the remains might be revealed when analyzing the postmortem skeletal modifications?
- Depositional context
- Biological taphonomic agents
- Transport and dispersal
- Cause and manner of death
What is subaerial bone weathering?
Decomposition of hard tissues as a response to natural agents in their immediate environment over time
List aspects of the depositional environment which impact the degree of weathering bone may exhibit.
- Solar radiation
- Wet-dry cycle
- Freeze-thaw cycle
- Heat-cool cycle
- Mineral crystallization
- Previous coffin burial
List and describe the stages of bone weathering, as discussed in lectures.
Stage 0: Bone shows no sign of cracking
Stage 1: Bone starts to crack, parallel to fiber structure
Stage 2: More noticeable cracks
Stage 3: Large cracks, might appear rough
Stage 4: The bone is rough in texture, some bone is falling off and having small openings
Stage 5: Bone is falling apart
Humans may serve as taphonomic agents. What does that sentence mean?
Humans can change how what happens to a body or other organic materials after death
List four categories of humans as taphonomic agents
- Criminal activities
Dismemberment, thermal
alterations, etc. - Funerary practices
Embalming, cremation, cemetery
burial - Alteration for cultural purposes
Anatomical teaching remains
Contemporary ritual remains
Trophy remains - Damage occurring during field
recovery, handling, and laboratory
analysis
What are trophy remains?
Human remains are preserved, and often displayed or kept as mementos or symbols of victory, conquest, or achievement
List taphonomic categories of trophy remains
- Original acquisition (ex: perimortem
trauma) - Ornamental alteration (ex: writing)
- Curation damage (ex: shelf wear)
What is the ancestry conundrum?
Most anthropologists state that “race is a social construct” lacking scientific validity. Yet, forensic anthropologists continue to provide estimations of ancestry (‘race’) based on the analysis of skeletal remains
Of the four main parameters of the biological profile, which is the least applied parameter?
Ancestry
Provide the anthropological definition of ancestry (biological affinity)
geographic region or ancestral origin of an individual
Anthropologists commonly divide ancestry into which three categories?
European, Asian, African
List common methods used to assess ancestry
Morphoscopic (shape)
Craniometric (size)
Other methods
Postcrania
Dental
DNA
Define trait list
set of characteristics or features used to categorize, compare, or describe different groups of people
Why are trait lists not considered best practice when assessing ancestry?
They are subjective, inaccurate, oversimplified,
Are trait lists used commonly by forensic anthropologists to assess ancestry?
Yes
What are macromorphoscopic (MMS) trait analyses?
apply cranial MMS traits scores to classification models with statistical frameworks
Define the following terms: character, character state, character score
Character - categories of morphological features (traits)
Character states - recorded variations of a character
Character scoring - assign a number to each character state
List seven cranial MMS traits as defined by Hefner (2009, 2014) and described in course lectures
Orbital shape, Anterior nasal spine, Inferior nasal aperture, Nasal bone contour, Interorbital breadth, Nasal aperture width, Nasal overgrowth
What is a discriminant function analysis (DFA)?
used to classify data into different groups based on a set of measurable features
Are morphoscopic discriminant function analyses used commonly by forensic anthropologists to assess ancestry?
Yes
How do DFA models work, using ancestry assessment as an example?
It builds a predictive model for group
membership
What is machine learning?
An artificial intelligence that teaches computers to learn without explicit programming
Which category of machine learning models shows the most promise when assessing ancestry?
Supervised Learning
How do machine learning classification models work, using ancestry assessment as an example?
Supervised learning trains a computer model on known input (MMS scores) and known output (ancestry) data to make predictions Classification models classify input data into categories (European, African, Asian)
Provide important caveats that must be considered when using analytical tools to classify human skeletal remains into “races”
Genetic ancestry markers, biological ancestry, and “social race” of an individual may not match
Describe the process of assessing ancestry using cranial MMS traits and Hefner’s (2014) discriminant function equations
Hefner (2014) provides discriminant function equations using 7, 5, and 3 variables (cranial MMS traits)
Describe the process of assessing ancestry using cranial MMS traits and the hefneR app
Same individual, same MMS scores Different analytical tool (Naïve Bayesian analysis), different ancestry categories
Using this classification model, the individual has a 48.59% chance of being Asian
Describe the process of assessing ancestry using cranial MMS traits and the macromorphoscopic databank (MaMD)
Uses an artificial neural network to classify an unknown cranium into a reference group. The reference data are housed in the Macromorphoscopic Databak
List two types of craniometric analysis methods
Indices – generally not advisable
Craniometric discriminant function analyses
Are craniometric indices used commonly by forensic anthropologists to assess ancestry?
Yes
Are craniometric discriminant function analyses used commonly by forensic anthropologists to assess ancestry?
Yes
What is FORDISC?
It is software using discriminant
functions to assess ancestry
How does a forensic anthropologist use FORDISC to assess ancestry of skeletal remains?
FORDISC identifies the most probable ancestry of the unknown individual based on the reference sample
Describe the utility of each of the following results pages to interpreting FORDISC results: measurement comparison page, classification table page, case classification page.
Measurement comparison page: helps you understand whether your sample’s measurements are typical or atypical
Classification table page: helps you understand which groups your sample is closest to in terms of skeletal measurements
Case classification page: gives you the final result of the analysis
Define posterior probability
likelihood of belonging to the respective group
Define typicalities
distances of the case from the respective group mean
Is FORDISC used commonly by forensic anthropologists to assess ancestry?
Yes
If an individual is typical for a group (≥ 0.05) and has a high posterior probability for it, then can a forensic anthropologist assume that it is likely to belong to that ancestry group?
Yes
Identify various methods used to estimate living stature in skeletal remains
Measurement of the skeleton in the grave
Anatomical methods
Mathematical methods
How does a forensic anthropologist obtain the total length of long bones? Be specific when describing how to obtain the total length of the tibia.
They make sure it is on a flat surface, identify the bones ends, and use a measurement device. As for the tibia
How does a forensic anthropologist obtain the physiological length (bicondylar length) of the femur?
Identify key landmarks and measure
How does a forensic anthropologist obtain the physiological length of the tibia?
Measure before the spines and before the medial malleolus, the weird point at the bottom
Describe the process of stature estimation using anatomical methods
To get someone’s height, you add up the lengths of all the bones that contribute to height, like the leg bones and spine. Then you add a bit extra for the muscles, skin, and other soft parts.
Provide advantages to using anatomical methods.
Provide limitations to using anatomical methods
Advantages
Not dependent on sex or ancestry
More accurate with less bias
Limitations
Requires excellent skeletal
preservation
Time consuming
Describe the Fully method of stature estimation.
Which measurements are taken for this method?
Obtain measurements
Cranial height
Vertebral heights
First sacral segment height
Femur bicondylar length
Tibia total length
Talus and calcaneus,
articulated height
Sum all measurements
Add soft tissue correction
How does a forensic anthropologist use mathematical methods to obtain stature?
Differentiate between univariate and multivariate regression formulae
Estimate stature from one or more bones using a regression equation
Univariate regression formula – measures one bone
Multivariate regression formula – measures multiple bones for that formula
Under what circumstances does the forensic anthropologist use the total length of the long bone when using mathematical methods of stature estimation?
When should the physiological length of the bone be used?
They use it often and the physiological length of the bone is used when measuring the tibia.
Describe the process of stature estimation using regression
formulae.
Provide tips to increase the likelihood of success
used to estimate things like a person’s height from the length of their bones
Do not average measurements
obtained from different formulae
Where possible, use a formula with the same sex, ancestry, and temporal cohort as the forensic sample
When choosing a bone(s) to
measure, use the formula with the
smallest standard error
What special considerations should be made when attempting to obtain living stature using the following skeletal elements:
- fragmentary limb bones
- skeletal elements other than limb bones
- skeletal elements with pathological conditions
- non-skeletal elements
- subadult skeletons
- mature adult skeletons
Fragmentary Limb Bones - reduced accuracy
Skeletal elements other than limb bones - generally not advisable
Skeletal elements with pathological conditions - provide caveats or exclude
Non-skeletal elements - materials have been used
Subadult skeletons - generally not advisable
Mature adult skeletons - stature decrease
Describe explanations for inconsistencies between stature estimates based on skeletal remains and known stature based on antemortem stature records
Biased self reports
Out of date records
Misreported
Describe explanations for inconsistencies between stature estimates based on skeletal remains and known stature based on measuring antemortem stature
Differing measurement techniques
Circadian variation
Describe explanations for inconsistencies between stature estimates based on skeletal remains and known stature based on measuring cadaveric stature
Missing Soft Tissue
Post-Mortem Changes
Biological Variability
At which three locations did forensic anthropologists work to identify human remains following the 9/11 attacks?
Temporary body collection point near Ground Zero
Fresh Kills landfill site on Staten Island
Temporary mortuary at the NYC OCME
What was one of the forensic anthropologists’ primary responsibilities as part of the multidisciplinary identification efforts?
help identify human remains
What activities were performed at the Fresh Kills forensic site?
process debris and search for human remains
What was the primary role of the FBI?
search for evidence (black boxes, hijacker weapons, etc.)
What was the primary role of the anthropologists?
distinguish human remains from other materials
Describe the process of identifying human remains at the OCME temporary morgue.
- Human remains transported from Ground Zero and Fresh Kills
- Held in preprocessing refrigerated trailer
- Initial assessment at triage station
- Escorts transfer remains to specialist teams
- ME examination
- Contents documented, photographed, sampled for DNA analysis
- Potentially other teams
Where are human remains stored until repatriation?
stored at the World Trade Center Memorial Repository
