ANTH Exam 2

biological profile

estimation of the deceased's sex, age, stature, population affinity, and trauma/pathology

sexual dimorphism

the differences in body structure between males and females that can be evaluated after onset of puberty

cranial features of males

• larger cranial vault compared to females.
• average brain size is approximately 200cc larger than that of females.

muscle attachment in males versus females

males have more pronounced attachments indicating greater muscle mass

skull features of males

• may have a prominent external occipital protuberance.
• typically displays a pronounced brow ridge.

orbital characteristics of males

squared orbits and smooth orbital margins.

mandible features of males

• angle of mandible more acute.
• mental eminence more pronounced.
• mastoid process is larger and more robust.

pelvic features of males

• subpubic angle: absent in males
• ventral arc: absent in males
• medial aspect of the ischiopubic ramus: dull and wide in males

cranial features of females

• Increased cranial bossing gives a more juvenile appearance.
• Rounded forehead with a sharp superior orbital margin.
• Reduced brow ridge compared to males.
• Forehead rises more sharply and vertically.

orbital characteristics of females

Rounded orbits and sharp superior orbital margins.

mandible features of females

• Angle of mandible more obtuse.
• More gracile

pelvic features of females

• Greater Sciatic Notch: Wider in females to facilitate childbirth.
• Subpubic Angle: Broader angle in females.
• Ventral Arc: More pronounced in females
• Medial Aspect of the Ischiopubic Ramus: Sharp and narrow in females
• Preauricular Sulcus: Present in females and serves as a trait for sex estimation.
• Parturition Scarring: Associated with childbirth-related changes in the pelvis

Phenice Technique (1969)

One of the most reliable and commonly used methods employed for sex estimation in skeletal remains

Three Techniques for assessing pelvic traits:

• Ventral Arc: A bony feature useful in sex determination.
  (absent in males)
• Subpubic Concavity: The inward curve of the pelvic bone.
  (absent in males)
• Medial Aspect of Ischiopubic Ramus: Shape is indicative of the biological sex present.
  (dull and wide in males)

Assesses whether these traits are present or absent

trajectory effect

The discrepancy between biological age and chronological age widens as people get older and is known as the trajectory effect.

• Ex: Some 90 y/os look 60 and vice versa

sex estimation based on patterning of costal cartilage calcification

Differing rates and patterns between males (marginal) and females (central).

sex estimation based on bone pathology

Males may exhibit bony tumors and gout; females may show rheumatoid arthritis and hyperostosis frontalis interna (HFI).

dental indication in juvenile age estimations

• Teeth eruption follows a specific sequence

dental development stages

• Based on research by Moorrees et al. (1963)
• Estimations are precise

Challenges with Juvenile Dental Estimation

• Uncertainties in dental eruption estimates (Ubelaker

age estimation for juveniles using skeletal measurement techniques

• Uses the metric length of diaphyses as an aging indicator
  • Long bone growth proceeds longitudinally and appositionally

pros and cons of using skeletal measurement techniques in age estimation for juveniles

• Pros: There is very little variation between sexes or different populations.
• Cons: This method is only useful until the epiphyses begin to fuse with the diaphysis

Epiphyseal union status

• Open

age estimation

a comprehensive understanding of the nature

biological age

the age determined by the physiological state of an individual's body

chronological age

the length of time a person has been alive

Does age estimation focus on biological age or chronological age?

• Focuses on biological age rather than chronological age
• Adjusts for individual variations and trajectories

Why is adult aging more complex?

• Aging adults is more challenging as growth has completed
• Involves degeneration in specific skeletal parts

Methods for Age Assessment

1. Morphological Changes

• Examination of joint morphology and movement limitations

1. Bone Structure Analysis
2. Dental Examination

Hartnett Method

Pubic symphysis method of age estimation using phases

• Focuses on the changing features found on and surrounding the face of the pubic symphysis

Indicators of Youth
Billowing

Specialized Aging Techniques

1. Auricular Surface (Ilium) Analysis
2. Sternal Rib Ends Analysis

Auricular Surface (Ilium) Analysis

The ilium is a limited movement joint that can be used for aging

• identified 8 phases in 5-year intervals for ages (20-60

Sternal Rib Ends Analysis

Hartnett Method for rib staging

• Work focuses on the 4th rib
• Observations of costal cartilage calcification (where the bone connects at the sternum to the costal cartilage)

Indicators of Youth
Billowy

Histomorphometry for Age Estimation

• Over an individuals lifetime

Kerley Method (1965)

• Focuses on osteon population density (OPD) as a measure of age estimation
• Examines intact osteons and fragments within bone

We have an individual with whole

intact osteons. Are they young or old?

Cranial Suture Obliteration

• General aging indicator based on ectocranial or endocranial surface scoring
• There is a general tendency for the sutures of the cranium and palate to close and obliterate with age
• Complete suture and palate obliteration is typically observed in older adults

Scoring system:
Open - 1

Common degenerative bone conditions

• Osteoarthritis: joint degeneration
• Osteoporosis: bone loss

When is the skeletal growth and development process complete?

when all permanent teeth have erupted

How can estimation of age from subadult remains be accomplished?

through the assessment of the degree of dental development

What is the most reliable area of the skeleton for adult age estimation?

the pubic symphysis

Metric Methods of Sex Estimation

Involves measuring maximum or minimum dimensions or taking measurements based on osteological landmarks to quantitatively evaluate size and shape differences between the sexes

What is the most reliable feature for sex estimation in adults?

Pelvis features are more reliable than those of long bones or skulls for determining sex.

Pelvis > Long Bones > Skull

Estimating Sex in Subadults

• Cannot be done the same way as with adults.
• Metrics of bones like humerus and femur could be considered

Population affinity

a measure of the genetic similarity between an individual and reference groups from populations

What causes human variation?

Human variation is caused by evolutionary processes such as natural selection

Gene flow

the transfer of genetic material between populations

Clinal Distribution

Gradual change in frequency of traits across different regions.

• Ex: Nose shape based on environment

Three main continental groups

Asian (including Native Americans)

Positive Assortative Mating

Individuals tend to mate with similar phenotypes (individuals with similar groups).

Admixture

Mixing of different ancestral groups.

Optimized Summed Scoring Attributes (OSSA)

A method of ancestry estimation that uses statistical analysis of morphoscopic traits

• Analyzes frequency of morphoscopic traits
• Example scoring system:
  American Black = 0

Decision Tree Modeling

-Regression-based model
-Limited to White

Anthropometry

Measurements of the human body

Osteometrics

Measurements of the body (skeleton)

Craniometrics

Measurements of the head (cranium)

Discriminant Function Analysis (DFA)

• A technique used for classification.
• Correlating variables to predict group membership

FORDISC Software

• Tool for analyzing craniometric data and generating probabilities of group memberships.
• Probabilities will be wonky if the individual doesn't belong to a specific group option

Interpreting FORDISC Output

D2: smaller value = more similar
Posterior probability: relative distance between groups
Typicality value: high value = more similar

Discriminant Function Analysis (DFA) in Teeth

• Examines dental crowns (excluding the third molar) across populations.
• Only has 3 groups: African

What is the limitation of Discriminant Function Analysis (DFA) in teeth?

Must have all crowns other than M3

What is the accuracy of Discriminant Function Analysis (DFA) in teeth?

88.1% for females

(hu)MANid

A software application called Human Mandible Identification (or (hu)MANid)

• Uses a combination of metric and morphoscopic analysis to classify human mandibles as either male or female and one of several population groups

What would you use to estimate sex and population affinity if you only had an isolated mandible?

(hu)MANid

What has more "racial" variation: the crania or the body?

The body has less "racial" variation than crania (as all human bodies are evolutionized for walking)

Which post-cranial elements have studied variation to estimate population affinity?

Tibia

What are the problems with post-cranial analysis to estimate population affinity?

• Less research on post-cranial elements compared to crania.
• High levels of intra- and inter-observer error noted in analyses.

Disease associations for population affinity

Certain diseases are related to certain population affinities (similar to sexes)

• Thalassemia: Common in Mediterranean populations.
• Paget's Disease: More prevalent in European ancestry.
• Rickets: Often linked to African populations.

Cranial suture variations in populations

• Metopism associated with European descent
• Extra-sutural bones common in Asians.

How do you determine subadult ancestry?

Genetic Indicators

• Utilizes mitochondrial DNA (mtDNA) haplotypes and Y-chromosome analysis for ancestry determinations.

Pros and cons of full skeletal measurement for stature estimation

Problems: This method can be very complex

Regression methods for stature estimation

• Used when you don't have a full skeleton
• Most commonly used method for estimating stature

What is the most commonly used method for estimating stature?

Regression methods (long bone analysis)

Can fragmented long bones be used in regression methods for stature estimation?

Fragmented long bones can be used

Can only one long bone can used in regression methods for stature estimation?

Using data from multiple long bones is generally preferred as it can lead to higher accuracy in stature estimation

What are the benefits and limitations of regression methods for stature estimation?

Benefits:
1.Only requires one long bone to make stature estimation

Problems

1. Less accurate than full skeletal measurement
2. Assumes no decrease in height (ex: scoliosis)

What factors can result in varied precision in regression methods for stature estimation?

• Assigned Sex at Birth
• Population Affinity
• Secular Change: Height can change over time due to factors like nutrition

Osteometry

Osteometry refers to the scientific measurement of bones

Can upper limbs be used in stature estimations?

The accuracy of stature estimations can vary based on the specific bones being measured. Upper limbs can be used (as they do have some correlation with height)

Stature Formulae

Calculation: Effective stature estimation can be achieved through manual calculations or software tools like Fordisc

Can non-limb bones be used in stature estimations

and if so

What non-skeletal context can also be used to estimate height?

In addition to bones

Body mass estimation

• Usually used to study groups rather than individuals (ex: historic hominims)
• Not accurate nor recommended
• Clothing size cannot be used as an indicator

What part/parts of the biological profile can be assessed using cremains? What part/parts of the biological profile cannot be assessed?

• If proper cremain practices were used

Subadult stature estimation

• There are limited methods available for estimating stature in subadults due to varying rates of growth and development stages.
• Children grow rapidly and vary a lot between individuals

Elderly adult stature estimation

• Age-related physiological changes

Kyphosis

excessive outward curvature of the spine

Biological Stature

True height

Cadaveric stature

• Measurements taken from deceased bodies (e.g.

Living stature

• Reported heights

Forensic Stature

• The relationship between estimated stature and reported stature can vary significantly
• Provides a very general stature range (plus or minus 2-3 inches)

Can stature estimation provide a definitive height?

It is advised to avoid definitive stature estimates in cases involving advanced skeletal diseases or abnormalities

idiosyncrasies

individual variations in morphology and configuration (human variation)

What factors cause congenital variation?

Genetics (mutations)

What factors cause developmental variation?

Degenerative

Normal skeletal variation

refers to the naturally occurring differences in bone structure and form that can be observed across populations and individuals. These features are present in normal bone anatomy but differ between individuals.

Differences in cranial sutures are an example of what?

Normal human variation

Skeletal anomalies

• Deviations from regular anatomical configuration; can be common.

• Anomalies are things that not everyone has

What are some examples of normal human variation?

Examples of normal variation include paranasal sinus configuration

Are skeletal anomalies rare?

Anomalies are things that not everyone has

True or false: having a metopic suture is an example of normal human variation.

False. Having a metopic suture isn't rare