Forensic Anthropology Final Exam

Cases

Closed cases: Cases that successfully identified missing persons, decedents and/or cause of death

Cold cases: Cases that have “gone cold,” remain unsolved in any of the above aspects

Closed Cases: The Romanov Murders About

• Czar Nicholas II reigned 1894-1917, last emperor of Russia

• Not universally liked, not considered a good leader

  • Khodynka Tragedy on his day of coronation → people trampled, killing 1200+

  • Bloody Sunday (1905) → Russian soldiers opened fire on peaceful protestors, killing 9

  • WWI outbreak

  • His wife, Czarina Alexandra took advice from the prophet/mystic Rasputin, who was not well-tolerated

• Nicholas and Alexandria had four daughters, one son

  • Son was heir

• Their household was managed by staff, including

  • Yergeny Botkin, family doctor

  • Alexei Trupp, the footman

  • Ivan Kharitonov, the cook

  • Anna Demidova, the maid

• In total, 11 people comprise the householdprophet/mystic Rasputin, who was not well-tolerated

• In 1917, Nicholas abdicates throne due to the Bolshevik Revolution (Russian Revolution)

• Family and staff flee to the Ural Mountain region to their fortified mansion in the mountains

• On the night of July 17th, 1918, they were urged to “flee to safety.” Anastasia, Tatiana, and Maria filled their dress linings with jewels. Maid Anna carried metal boxes with jewels in pillows

  • This urge was a trap. All were taken prisoner, amurdered in the house basement

Closed Cases: The Romanov Murders

Narrative from witnesses:

• Only the death of the czar announced

38 shots at the whole family

• The jewels sewn into the girls’ dresses protected them from gunfire. They were bayoneted, bludgeoned and shot in the head

Bodies dumped in pit, covered in sulfuric acid to cover the smell

Alexei (son) and one of his sisters were cremated and not buried with their family.

Some people believed Anastasia had escaped.

• Animated film Anastasia

In 1979, a grave was found in the region where the Romanovs were killed.

Soviets kept the grave location a secret until the Union fell in 1991

• Initial forensic work by Drs. Peter Gill, Pavel Ivanov

• American team in 1992

Analysis found 5 females, 4 males

Closed Cases: The Romanov Murders

1)

• Adult, middle aged female (pelvis)

• Mandible had poor quality dental bridge

• Ankle joint had squatting facets, suggesting repetitive crouching or kneeling

2)

• Adult, older male (pelvis, cranium)

• Antemortem loss of upper teeth

• 1 bullet in pelvic region, 1 in vertebrae

• Gunshot wound on left forehead

3)

• Young adult female, early 20s, based on root development of M3 and fused epiphyses

• Stature: 5’4’’

• Extensive molar fillings

• Gunshot wound to jaw that exited thru forehead

4)

• Middle aged male, based on cranial morphology

• Short stature

• Joint deformation on pelvis consistent with horse riding

• Poor dental health

5)

• Late teens/early 20s female, based on root tips of M3 incomplete, sacrum not fully developed

• Stature: 5’6’’

6)

• Adult female based on pelvic development and fusion of the clavicle

• Gunshot wound to back of the skull

7)

• Older adult female

• Possible perimortem trauma on ribs

• Expensive dental work (precious metals)

8)

• Heavily damaged by acid

• Middle adult male, 40s, estimated by cranium

• Healed ulna fracture

9)

• Large older adult male

• Heavily worn teeth

Closed Cases: The Romanov Murders

Narrative from witnesses:

• Only the death of the czar announced

• 38 shots at the whole family

• The jewels sewn into the girls’ dresses protected them from gunfire. They were bayoneted, bludgeoned and shot in the head

• Bodies dumped in pit, covered in sulfuric acid to cover the smell

• Alexei (son) and one of his sisters were cremated and not buried with their family.

• Some people believed Anastasia had escaped

• Animated film Anastasia

Closed Cases: The Romanov Murders Findings

• In the 90s, researchers also conducted mtDNA tests to prove the relatedness of the bodies

• Confirmed genetic sex and familial relationship between the mother and children

• Using living descendants, there’s a 99% probability that the skeletons belong to the Romanov family

• In 2007, a small pit 70 m away from Grave 1 was found

• Contained the remains of 2 individuals: 1 male and 1 female

  • DNA tests confirmed they were related to the Romanovs

• Alexei and Maria/Anastasia

  • Can’t confirm which

• Forensic work was able to:

  • Successfully identify remains through contextualized biological profiles

  • Confirm parts of the narrative about trauma (bullets vs. bayonets

Closed Cases: Homicide, The Murder of Nicola Brown Simpson; California vs. OJ Simpson (1994)

• Bodies of OJ Simpson’s ex-wife, Nicole Brown Simpson, and ex-wife’s lover, Ronald Goldman, found night of June 12th

• DNA from OJ, Nicole, and Ronald found throughout OJ’s estate and car, along with gloves at both the scene of the crime and OJ’s house

• Despite overwhelming evidence against him, jury finds him not-guilty on all counts of murder

• Remember – very first DNA used in criminal case only 1987 in England

• Very new technology at the time, but this case brought it DNA into the realm of public knowledge

• Excellent example of non-scientific aspect of forensics/justice

  • If cases go to trial, what matters is not technically scientific precision

  • Rather, what matters is the opinion of a jury of your peers

Closed Cases: Homicide, The Murder of Caylee Anthony (2008)

• Orlando, FL

• After not being seen for weeks, 2-year-old Caylee Anthony was reported missing by her grandmother, Cindy Anthony

  • Said her daughter, Casey’s car smelled like death

• December 2008, Caylee’s skeletal remains were found in a trash bag in the woods near the Anthony home

  • Forensic evidence finds duct tape near the mouth

  • ME: “homicide by undetermined means”

• At trial, the defense says Caylee drowned in the family pool on June 16th and that Casey’s father buried the body. Also asserted abuse by father as a child

• July 5th, 2011, Casey Anthony found not guilty on all charges except for lying to a police officer

• Caylee’s Law: felony offense if legal guardian fails to report child missing

Closed? or Cold? Serial Killers

John Wayne Gacy Murders (1978)

• The “Killer Clown”, Chicago area

• Humans in different part of decomposition process laid around the house.

• Forensic anthropologists identify 33 victims, most of which were young males.

• Victims identified by cross-referencing with missing persons reports.

  • Five still unidentified

• Convicted of the rape and murder of 33 boys and men. Executed May 10th, 1994

Cold Cases: Serial Killers

“Black Dahlia” (1947)

• Gruesome murder of 22-year-old Elizabeth Short

• Body mutilated in clean cut

• TW: disturbing images if you search the case

“Zodiac Killer” (1968-1969)

• Northern California

• Claimed 37 deaths, only five confirmed by forensic evidence

Cold Cases: Structural Violence

• Missing and unidentified persons in the United States: the nation’s “silent mass disaster”

• Statistics in the us

  • 85,000 active missing persons

  • 40,000 unidentified persons

  • 4,400 unidentified human remains found annually

    • 1,000 remain unsolved after 1 year

Exacerbated by

• Inconsistent maintenance and reporting of birth/death certificates by state laws lead to nation-wide difficulties with investigations

• Inconsistent handling of unidentified remains → some in ME/coroners offices, some buried in unmarked graves or cemeteries

Missing persons or unidentified cases voluntarily collated into the National and Missing Unidentified Persons System (NamUs)

76% of unidentified remains may never be identified due to issues of decomposition, traumatic injury, scavenging or poor recovery

Studies of cases from 1979-2008 found

• Over 80% of unidentified decedents were male

• Death rates are highest among African Americans in major cities and in the SW US

• Homicide victims are most often young adults, unidentified women and children

• Women and children disproportionately victims of domestic homicide

“Many researchers argue that the distribution and geographic variation of unidentified persons are likely related to trends in homelessness, sex work or human trafficking, and irregular border migration. Consequently, unidentified persons in the United States often represent the most vulnerable and transient groups among us: our homeless, runaways, foreign-born individuals, and under-represented minorities”

Unidentified remains in contexts perceived to be self-destructive or deviant receive fewer resources in identification → poor change of solvability

“In other words, thousands of people who experience the highest rates of social exclusion, violence, premature death, and overall poor health outcomes continue to be marginalized in death

Goad’s suggestion to make cases more solvable

1. Incorporate the “biocultural” profile

• Biological profile: Age, sex, stature, ancestral group, pathology etc.

• Cultural profile: geographic area of recovery, personal effects, body modifications, etc.

2. Foster positive relationships with marginalized communities

• Family advocacy improves acquisition of medicolegal records

• Public outreach builds community confidence in law enforcement

Biomolecules

Biomolecules are “large organic compounds found in living organisms and sometimes present, usually in a partly degraded state, in the remains of those organisms after their death”

We are going to include stable isotopes in that definition

Multi-”omics”

• Genomics deals with DNA, which is found in all organic material and soils

  • RNA doesn’t last very long and doesn’t tell us much DNA can’t

• Proteomics deals with proteins, which are found in similar places to DNA, as DNA codes for them

• Metabolomics deals with lipids and carbohydrates, which are residues of fat, oils, resins and starches

• Isotopes are not biomolecules, perse, but are contained within the other biomolecule classes and their analysis is conducted with bulk protein or lipid preps

Biomolecules in Forensics

• Study biomolecules from teeth, bone, hair, and nails

• For forensic contexts, lipids, proteins, and carbohydrates are less commonly studied, while DNA and isotopes are more commonly studied

DNA is frequently used in forensic contexts

Cases solved with DNA

• Golden State Killer

• Boston Strangler

• Fawn Mari Cox Murder

• Susan Berman Murder

• 1975 Teree Becker Cold Case

First DNA case

Leicestershire England

• Victims:

  • November 21st 1983, 15-year-old Lynda Mann

  • July 31st 1986, 15-year-old Dawn Ashworth

• Semen recovered, only blood type able to be reconstructed

• False confession wrested from local 17-year-old boy with learning disabilities, Richard Buckland

• Eventually, Colin Pitchfork DNA matched to that of the semen sample

  • Pitchfork’s parole was reviewed and denied 2025

  • Point being – very recent technology

DNA

Exons: Protein coding portions of the DNA

Introns: Non-protein coding portions of the DNA

• Do all sorts of stuff you don’t need to know about

• Esp. gene regulation

Deoxyribonucleic acid

• In contrast to RNA – Ribonucleic acid

Stores biological data

• Chromosomal sex

• Ancestry

• Pathogens

• Biological relatedness (phylogenetics)

String of nucleotide bases (Adenine, Cytosine, Thymine, Guanine) = polynucleotide chain

Adenine always pairs with Thymine

Cytosine always pairs with Guanine

In coding DNA

• Every 3 base pairs forms a ‘codon’

• Codes for a specific amino acid

• Amino acids combine to form proteins

DNA - Chromosomes

• DNA found in chromosomes in the nucleus of each cell

• Each human cell nucleus has 23 pairs of chromosomes (one inherited from each parent)

  • 46 in total

• Segments of chromosomes that code for proteins are called genes

  • Alternative forms of the same gene are called alleles

DNA - Genome

• Complete set of genetic material is called a genome

• Not all portions of the genome code for proteins

• “There are approximately 1013 cells in the adult human body, and each one has its own copy or copies of the genome…”

22 sets are autosomes

1 set are sex chromosomes

• Males: XY

• Females: XX

XX and XY chromosomes are passed down differently

Females pass down genes located on each X chromosome to offspring. Each offspring has a unique combination of genes

• The two X chromosomes undergo recombination, exchanging material

• True of males and females

Males pass down their X chromosome without recombination because it lacks another X counterpart

Y chromosomes likewise do not undergo recombination, so they are passed down without change

DNA

• Single nucleotide polymorphisms (SNPs) are variants at a single nucleotide location

• Any time a polymorphism occurs, a new “branch” is created

• The SNPs are passed down, therefore frequencies vary by population

• Each offspring has a mixture of maternal and paternal SNPs → record of grandparent polymorphisms, etc. → ancestral group = haplogroups

• Groups of repeating DNA nucleotide bases are called short tandem repeats (STRs)

• Help establish a likelihood of genetic proximity (family relationships) based on shared # of repeats

DNA

Remember: each cell contains all 23 sets of chromosomes in its nucleus

1) Nuclear DNA→ a.k.a autosomal DNA. Found in cell nucleus of all chromosomes. Reflects the DNA of the 22 autosomes

Contains genes that code for physical appearance (phenotype)

2) Y chromosome DNA → found in cell nucleus. Useful for tracing paternal lineage

If females have 2 sets of X chromosomes in their cell nucleus, how could we differentiate between mother’s maternal lineage and father’s maternal lineage?

3) Mitochondrial DNA (mDNA)→ found in cell mitochondria on X chromosomes. Transferred between females via egg cells. No sperm involvement

Mitochondrial genome shorter and more copious than nuclear genome, more likely to survive in badly degraded cases

• mtDNA: thousands of copies per cell, nuclear DNA: two copies per cell

• mtDNA: 16,500 bases long, nuclear DNA: 3.2 billion bases long

• Why do mitochondria have their own DNA?: “Endosymbiosis”

DNA

• SNPs on Y chromosome DNA and mtDNA male and female lineages, respectively

• Fall into haplogroups (Haplo means “one”)

What samples studied for DNA?

Organic components found in skin, hair, blood, semen, and vaginal fluids

• Anything with cells!

Will discuss more about these types of evidence in a few weeks

How is DNA studied?

• In the past: Polymerase Chain Reaction (PCR)

• Amplifies extant endogenous DNA to allow for typing

• Cycle of heating and cooling essentially zip and unzip, allowing for sequences to copy

• Take finalized solution and put it into a…

• Agarose Gel Electrophoresis allows for visualization of PCR

• Principles of Gel Electrophoresis

  • DNA has a specific charge and length

  • Agar gel is electrified

  • Longer chains make it less far

• Doesn’t require sequencing entire genome

  • Allows for a focus on a few specific genes likely to be variable and preserved

• PCR was invented by Kary Mullis

• Probably one of the most important discoveries in the history of science

• “It's impossible to overstate PCR's impact. The ability to generate as much DNA of a specific sequence as you want, starting from a few simple chemicals and some temperature changes—it's just magical”

  • David Bilder

• Today: Next Gen Sequencing (NGS)

• Benefits = “Hypothesis-free” approach, higher discovery power; High throughput = less cumbersome for large samples or samples with many regions of interest

• Require calibration with libraries

  • Portions of genomes made of different lengths

  • Human genome project (completed in 2022)

• A common method is Illumina

NAGPRA - Native American Graves Protection and Repatriation Act

Federal Law

• Human remains, funerary objects, sacred objects and objects of cultural significance held by public entities to be repatriated

Two criteria:

• Native American

• Tribal affiliation

Kennewick Man

• Discovered in 1996 in Washington by two college students

• Police called, thought to be a forensics case as the skull did not ”look” Native American, but “Caucasoid”

• A prehistoric spear point embedded in the hip-bone cast doubt on it being a “forensic” case

• Radiocarbon dating (C14) confirmed that remains were > 9000 years old

Three groups vied for authority over the remains:

1) After learning the ancient nature, Army Corps of Engineers (in charge of the land where bones were found) claimed authority over them, forced all scientific study to end, and put into an evidence locked at the sheriff’s office pending review.

• County coroner protested saying he had legal jurisdiction

2) A coalition of Columbia River Basin tribes and bands claimed the skeleton under NAGPRA and demanded the bones back for reburial.

• “From our oral histories, we know that our people have been part of this land since the beginning of time. We do not believe that our people migrated here from another continent, as the scientists do.”

3) James Chatters enlisted his friend and colleague Doug Owsley (National Museum of Natural History), a well-respected forensic anthropologist who ran cases for the CIA, the FBI, the State Department and various police departments. They wanted to study the remains due to their rarity.

• Owsley argued that they should be able to study the remains, as the skeletal remains bore no evidence of relatedness to any existing tribes. The skeleton lacked physical features characteristic of Native Americans

• The Army Corps told the tribal coalitions that they would eventually receive the remains after a window of open investigation was closed

  • The remains had to be studied forensically in order to find tribal affiliation, otherwise NAGPRA was not applicable

• The Army Corps was about to repatriate remains when Chatters, Owsley and a small group of scientists sued the US government and various Army departments. Lawsuits lasted years

• Remains moved around, mysteriously portions of the femora were removed, FBI launched investigation. Portions later found in the county coroner’s office...

• Scientists won lawsuit in 2002 (7 years later), with courts agreeing remains could not be Native affiliated

• Scientists studied remains intensely, felt features were most consistent with modern Polynesians

• “…the tribes continue to believe that Kennewick Man is their ancestor. They want the remains back for reburial. The corps, which still controls the skeleton, denied Owsley’s request to conduct numerous tests, including a histological examination of thin, stained sections of bone to help fix Kennewick Man’s age. Chemical analyses on a lone tooth would enable the scientists to narrow the search for his homeland by identifying what he ate and drank as a child. A tooth would also be a good source of DNA. Biomolecular science is advancing so rapidly that within five to ten years it may be possible to know what diseases Kennewick Man suffered from and what caused his death.” (2014)

Kennewick Man = The Ancient One

• Five tribes involved in repatriation: Colville, Yakama, Nez Perce, Umatilla and Wanapum

• President Obama signed bill repatriating remains

• Reburied in 2017 in undisclosed location

Proteins

• Coded by DNA

• Provide structure (e.g., collagen, osteocalcin, hemoglobin) and function in a number of other capacities

  • Subunits are amino acids, which connected via peptide chains

• Robust and highly diagnostic

• Widely studied as proteomes = proteomics

• Forensic Proteomics studies proteins to identify body fluids and tissues = serology

  • Different fluids and tissues have differently expressed proteins

  • E.g.: Hemoglobin in blood

• Proteomes are sensitive to behavior and the environment

  • Saliva proteome is dynamic in response to smoking and daily fluctuations in the microbiome

    • Seminal and vaginal proteomes, sweat and vomit

• Can be used when DNA is too damaged for

  • Fingerprints → trace left on surface

  • Species identification → species-specific proteins

  • Sex estimation → sex specific proteins

  • Postmortem interval → degradation rate of proteins

Every contact leaves a trace

• “Every contact leaves a trace” = Locard’s Exchange Principle

• Whenever two objects come into contact, there is a transfer of material.

• Usually, this transfer is done without notice, making it ideal for forensics

• Any detected transfer can associate objects, individuals, or locations with one another, however, the strength of the association varies

• Rarely leaves identifying information at the level of the individual

• Rather, can help reconstruct the series of events that took place at a scene

Studied by mass spectrometry (MS)

Analytical machine that identifies molecules by observing the behavior of their ions in varying electromagnetic fields.

• This behavior depends on the varying mass-to-charge ratio (m/z) of the ions.

Sample is first ionized

Magnetic sector MS

• Samples pass through magnetic fields, those with more inertia (heavier) won’t bend as much as those with less inertia (lighter)

• Beam hits the detector at different locations, detecting the ions

Time of flight (TOF) MS

• Measures speed, rather than weight

• Magnetic pulse propels ions down and whichever hits the detector first is lighter

Mass spectra

• Output of a mass spec

• Compared to known sample

Major types of trace evidence: Fingerprints

“The product of the contact of papillary ridges—present on human beings’ fingertips, palms, and soles—with a surface; this interaction transfers sweat and skin components to the material, leaving a particular mark.”

Premise: While fingerprints contain similar components, the chemical content varies by demographics and patterns are idiosyncratic

• Shape and size of blood vessels, growth speed, intrauterine environment, all influence pattern

• Even identical twins have different fingerprints!

Fingerprint patterns relatively stable

Solves ~10x more cases than DNA

Chemical studies can also tell how long it has been since the fingerprint was left

• Fatty acids studied via mass spectrometry

Most sweat and chemical compounds sit in the ridges of the fingerprints initially, but over time moves out of the “ridge” and into the “valley”

• Looks at diffusion rate

Latent fingerprints are those identified with powder or liquids, which fall into the print’s valleys

Different powder for different substrates

”lifting prints”

Stable Isotope Analysis

Main underlying principle: “You are what you eat”

• …and drink and breath…

• The food you eat partially becomes energy

• The food you eat partially becomes you

The physical composition of your body comes from metabolic processes

• Anabolism = building

• Catabolism = breaking down

This is very helpful for biological anthropologists

Important parts of the atom for this class

• Nucleus: Dense, positively charged center.

  • Proton: Positively charged subatomic particle

  • Neutron: Neutral subatomic particle

• Electrons: Negatively charged subatomic particles

  • ”Orbit” the nucleus

If you remove…

• Proton: Different element

• Electron: Different ion

• Neutron: Different isotope

Stable isotopes

Stable isotopes are isotopes that do not undergo radioactive decay.

• Can be light or heavy based on atomic mass

Analyzed via mass spectrometry

Interpreted by the ratio of an element’s heavier form to its lighter form (e.g. 13C/12C)

• Reported using delta notation (δ), expressed in parts per thousand (or per mil) (‰).

Isotopes

Atoms of same element with same number of protons and electrons, but different number of neutrons

• Variability in atomic mass

Naturally occur in the environment

When an organism consumes (and metabolize) food and water, it incorporates the source’s elemental composition

• You are what you eat!

• The carbon atoms in your bones are from your food and the air

The heavy and light isotopes are separated in a chemical reaction process called fractionation.

• Prefers lighter isotopes over heaver ones

Unstable isotopes

Carbon 14

• After death, it begins to decay

• Radiocarbon dating

Chemical reaction between sunlight, the atmosphere, photosynthesizing plants, and their consumers

• All elemental signatures come from our environment

Tissues Studied for isotopes

Any tissue in sufficient quantity

• Best characterized tissues are…

• Hair, nails, teeth, collagen

Collagen → bone → remodels throughout life

• Analyzed via bulk averages

Carbonate/Apatite (Ca10(PO4)6(OH)2) → teeth → develop in childhood

• Analyzed via incremental sampling

Timeline

• Hair: ~1 cm/month

  • 1-2 week lag between dietary intake and root composition

• Nails: ~1-4 mm/month

• Bones: ~7 year average

• Teeth: Window into childhood

Carbon Isotopes

• δ^13 C/^12 C

• Speaks to plant consumption (direct or indirect)

• Photosynthetic pathway of plants

  • C4 vs. C3

  • E.g. Corn (maize) = C4 | wheat = C3

• Baseline: Know local plants!

  • Challenging in

Nitrogen Isotopes

• δ^15 N/^14 N

• Measures the trophic effect of meat protein consumption

  • Also helps differentiate aquatic vs. terrestrial animal diet

  • Aquatic soil δ 15N is more positive than terrestrial soils

• Vegans would have a “herbivore” diet

Oxygen Isotopes

• δ^18O/^16O

• Measures consumption of meteoric waters, which vary across (and within) landscapes

• Rainwater, freshwater, differs across latitude, altitude and distance from the sea

• Fractionation in the water cycle (evaporation, condensation, precipitation) leaves the heavier isotope (18O) behind

Human behavior influences isotopes

• Mobility → changing Sr across teeth

• Manuring soil → increases N

• Cooking food → increases or decreases O, C, N

• Starvation → increases N

• Breastfeeding → increases N

Strontium Isotopes

• 87^Sr/86^Sr

• Reflect local geological signature

  • Variation in 87Sr depends on amount of decaying rubidium in rock during formation

  • Varies from 0.720 – 0.703 on land

• Plants uptake strontium into their tissues

• Consumers uptake plant strontium into their teeth

  • Strontium substitutes for Ca in hydroxyapatite

• Baselines: local fauna

• 87^Sr/86^Sr

• Reflect local geological signature

  • Variation in 87Sr depends on amount of decaying rubidium in rock during formation

  • Varies from 0.720 – 0.703 on land

• Plants uptake strontium into their tissues

• Consumers uptake plant strontium into their teeth

  • Strontium substitutes for Ca in hydroxyapatite

• Baselines: local fauna

Histology

The microscopic study of tissues

• Includes soft (skin, muscle, etc.) and hard tissues (bone, teeth)

• Forensic Histopathology → study of tissues or biopsies to determine pathology (illness) in living patients and decedents. Make diagnosis based on findings (e.g., is it cancer, what type, etc.)

Hard Tissues

Bones are recording structures, which means they “respond to changes of physiological condition of an organism by changing their morphological characteristics as they grow.” (Klevezal 1996, 1)

Enamel Histology

• Similar periodic growth (and growth arrest) characterizes the histological structure of tooth enamel and dentin

• Study of incremental development of dental tissues => periodicity

• In enamel, Striae of Retzius develop at a periodicity of ~8-9 days in humans; Cross striations: daily

• What does this mean?: Daily (24 h) record of circadian rythym, stress events recorded

• Remember, teeth start developing in utero!

• The neonatal line (NNL) applies the same premise to the birth event--> more stressful the event, the more accentuated the line

• Also visible in bone

• By this premise, unborn children lack a NNL

• Children born via c-section experience less stress and have thinner NNLs

Teeth

• Tooth enamel forms from tip of cusps down to roots in layers known as perikymata.

• During stressful life events experienced when the enamel was forming, perikymata may become exaggerated. These cessations of enamel growth are called linear enamel hypoplasia (LEH)

Cementochronology

Unlike enamel and dentin, cementum continues growing throughout the entirety of life

1 light + 1 dark band = 1 year

Count up band pairs, add to age at which tooth root forms

More precise than other aging methods for adults

During reproduction (gestation, lactation), elemental composition of bone changes

Pathology

• The study of disease. From the Greek pathos (suffering)

• Ever-evolving, expanding understanding of how disease affects humans

• We only observe lesions (NOT the disease itself)

  • From skeletal remains, differential diagnosis is often as good as you can get

• Important to understand etiology

  • Number of causes result in the same outcome

• Example: “This individual exhibits lesions consistent with cribra orbitalia which are a nonspecific indicator of stress that can reflect either prolonged nutritional deficiency or anemia

NAMUS (National Missing and Unidentified Persons System)

A U.S. database that helps match missing persons with unidentified human remains by collecting and comparing forensic data such as DNA, dental records, and biological profiles

• Connects:

  • Missing persons cases

  • Unidentified bodies

• Used by:

  • Law enforcement

  • Medical examiners

  • Forensic anthropologists

• Includes:

  • DNA

  • Dental records

  • Case details

What is violence?

WHO: “The intentional use of physical force or power, threatened or actual, against oneself, another person, or against a group or community, that either results in, or has a high likelihood of, resulting in injury, death, psychological harm, maldevelopment or deprivation.”

Three types of violence:

• Direct Violence: Actions and behaviors that cause physical harm

• Cultural Violence: Social constructs and ideologies that encourage direct violence

• Structural Violence: Institutions and structures that perpetuate violence

Trauma types

• Force Fractures

• Blunt Force Trauma (BFT)

  • Medium velocity impact

  • Typically shows radiating fractures

• Sharp Force (SFT)

  • Low-velocity impact

• Projectile Force Trauma (PFT)

  • High-velocity impact

  • Differentially beveled

Force Fractures

• Defines as the interruption of bone’s structure, as either a fissure or complete break.

• Bones fracture in different ways because of difference in biomechanical force

Transverse Fracture

• Fracture occurring from a force perpendicular to the bone’s main shaft (shear force)

• Splits the bone into superior and inferior halves (or medial and lateral in the clavicle)

Oblique Fracture

• Bone fractured from a strong force hitting on a plane diagonal to the long axis of the bone

  • Shear force on a diagonal plane

• Tends to occur on long bones

Spiral Fracture

• Like an oblique fracture, but bone fractures across both transverse planes

• Caused by a ‘twisting’ force, or torsion, where oblique is caused by a heavy force at a diagonal angle

Comminuted Fracture: Butterfly Fracture

• Large, triangular fragments of bone common to comminuted fractures

• Comes from bending force and axial loading

• Two oblique fracture lines meeting

Avulsion Fracture

Sudden dislocation caused by muscular contraction detaching or tearing a fragment of bone away from the main body

Impacted Fracture

• One end of the bone impacts the other end of the bone, and this force causes one end to jam toward the other (compression force)

• Creates wedge-like fusion of bone

• Compression force

Fissure/ Hairline/ Stress Fracture

• A crack extending from a surface into, but not complete through, a bone

• Caused by accumulated insult to one area (chronic), rather than a singular stressful event (acute)

• Common in athletes

Greenstick Fracture

• Usually occurs in children >10 yrs

  • Green = fresh

• Bone bends and breaks, but the break does not extend across the whole bony surface

Special: Parry Fracture

Generally, occur during moments of self-defense, usually involves the ulna

• Can also affect the clavicle, humerus, and distal radius

Special: Colles’ Fracture

• Fracture of the distal radius

• Comes from protecting oneself from a fall

• Impacted fracture specific to the distal arm

• Shearing force

Special: Boxer’s Fracture

• Fracture of the 4th or 5th metacarpal

  • Most often affecting MC 5

• Comes from striking an object/person with a closed fist

Facial Fractures

• Type I: Fracture line separates the upper dental arch from the rest of the face

• Type II: Involves the maxilla and extends through the nasal bones, crossing the orbit and orbit’s margin

• Type III: The line is transverse and high, producing a separation between vault and face

Sharp Force

• Injury from an instrument with beveled edge

• i.e. knife, box cutter, razor blade

• Most deaths by sharp force are homicides

• Slow velocity

• Kerf: a cut or incision made by a sharp instrument

• Analyze ‘kerf walls’ and ‘kerf floors’ to determine type of instrument

Blunt Force Trauma

• Often associated with a violent event

• Caused by large, heavy objects with a blunt edge striking the body

  • i.e. baseball bat, club, hockey stick

• Different areas of bones will react differently depending on the structural integrity of the bone

  • Also depends on severity of hit

• Bone collapses and shatters

Hacking and Chopping

• Contains elements of blunt and sharp force trauma

• Larger wounds than sharp force (wide “V”), sometimes radiating fractures like blunt force

• Kerf striae often found perpendicular to floor

Projectile/Ballistic Trauma

• Fast-moving small objects

• Can perforate (only enter) or penetrate (fully pass through)

• Entrance and exit leave different patterns

• Radiating fractures

Projectile/Ballistic Trauma

Bullet caliber and shooter position influence appearance of lesions and directionality

Entrance and exit wounds differ depending on the distance between shooter and victim and bullet caliber

Close-range

• Weapon-to-target

  • Entrance wound has ragged appearance

  • Bone may be blackened

• “Burning shots”

  • Shots of <15 cm

  • Entrance wound circular

  • Some blackening of bone possible

Short-distance (60-70 cm)

• Entrance wound circular

• No blackening of bone

Long-distance (70+ cm)

• May only perforate, not penetrate bone

• Depends on bullet caliber

Bullet caliber and shooter position influence appearance of lesions and directionality

Kerf distinction by:

• Size

• Shape

• Distance between blades

• Angle of blades

• Direction of mark

• Depth of the mark

• Power of the mark

• Mechanical? Manual?

Keyhole Lesion

• When a projectile object skims bones

• Both an entrance and exit wound in the same feature

How does bone heal?

Irregular Healing

Pseudarthrosis

• When broken bone fails to fuse

• Usually occurs from a lack of immobility, bad or absent treatment and alignment

• Each broken piece heals as its own element

Left: When a poorly set bone fuses.

Right: When a poorly set bone does not fuse

Types of “Diseases”

Vascular

Inflammatory (infectious)

Traumatic

Anomaly (congenital/non-metric)

Metabolic (anemias/gout, etc.)

Interaction (neuromechanical)

Neoplastic (tumors/cancer)

Vascular Disease

• Diseases involving blood and the vessels which carry it

• Reduced blood flow to the limbs

• General appearance is increased vascularity

Examples: Thalassemia, anemia

Inflammatory or Infectious Disease

• Contracted virus or bacteria

• Area inflames

  • Increased blood flow

  • Pooling of blood

• Infection festers

  • Microorganisms multiply

• Infection spreads

  • Can spread locally (within an organ, or adjacent space)

  • Can spread systemically (through the blood or lymph nodes

Pathology: Inflammatory or Infectious Disease Example: Periostosis

• Extremely common, from a traumatic event or numerous illnesses

• Inflammation of the bone’s periosteum (outer layer of tissue)

• Results in wood-like, bubbled texture on outside of bone

Pathology: Inflammatory or Infectious Disease Example: Dental abcesses & caries

Abscesses form when food particles get stuck between teeth and bacteria festers

Dental caries (=cavities) form from acid-producing bacteria

Pathology: Inflammatory or Infectious Disease Example: Leprosy (Hansen’s Disease)

• Spread via air

• Symptoms include skin lesions and muscle weakness

• Loss of sensation in digits and eventual loss of the digits

• Destruction of nasal cartilage

Pathology: Inflammatory or Infectious Disease Example: Tuberculosis (TB)

• Spread via air droplets

• Acute or chronic infection of soft or skeletal tissues by bacteria

• Affects the lungs (and by proxy, nearby bones)

• Can result in vertebral degradation (Pott’s disease)

Pathology: Inflammatory or Infectious Disease Example: Venereal Syphilis

• Can be sexually transmitted or transmitted from mother to child (breastfeeding)

• Affects the soft tissue as skin ulcers, sores on genitalia, benign growths

• Mainly affects tibia (saber shin) and cranial vault (stellate scarring)

Anomalies/ Congenital Disease

• Caused by pathological changes in normal development during intrauterine life

• May be hereditary or acquired between fertilization and birth

• Bottom line: something someone is born with

Pathology: Anomalies/ Congenital Disease Example: Facial cleft

• Cleft lips, cleft palates

• Caused by the failure of various tissues to fuse in early embryological development

Pathology: Anomalies/ Congenital Disease Example: Congenital syphilis

• Passed to baby during pregnancy

• Can be treated if caught early in fetal development

• Results in destruction of the facial skeleton, mostly the nasal area

Metabolic Diseases

• Diseases affecting the body’s ability to continue cellular processes

• Encompasses issues with converting food to fuel for proper function of the body, and hormone deficiencies

• General appearance: small pitting on bone surface, growth arrest or bone breakdown

Pathology: Metabolic Diseases Example: Osteoporosis

• Less estrogen hormone production => less bone production

• Trabecular bone loses density quicker than bone can rebuild itself.

• More common in older females

• Can lead to collapse of vertebral column

Pathology: Metabolic Diseases Example: Linear Enamel Hypoplasia (LEH)

• Episodic stress events result in enamel growth arrest during development

• Episodic stress events result in enamel growth arrest during development

  • Enamel stops being deposited while tooth continues to grow

• Can estimate age of stress event based on location on tooth

Pathology: Metabolic Diseases Example: Harris Lines

• Episodic stress events result in bone growth arrest during development

• Can estimate age of stress event based on location on skeleton

Pathology: Metabolic Diseases Example: Cribra orbitalia and Porotic hyperostosis

• Porosity of superior orbit or cranial vault

• Nonspecific indicator of stress

• Malnutrition, illness, anemia

Pathology: Metabolic Diseases Example: Vitamin deficiencies

• Lack of vitamin C → scurvy

  • Impairment of collagen synthesis, defective osteoid formation

• Lack of vitamin D → Osteomalacia and rickets

  • Rickets = Softening of bones in childhood, weight bearing bends bones

Mass Fatality Incidents

Events that result in a large number of dead

• Exs. Famine, fire, floods, viral epidemics, terrorism (and more)

The number of injured, sick, dying or dead victims overwhelms local or governmental resources

Forensic anthropological goals are to identify decedents, CoD, MoD within a closed population

• Closed population = we have some sense of who could be present

• Open population = could be anyone

Can have a high degree of fragmentation and commingling (unsure who is who)

• Examples: Hurricane Katrina, Challenger space shuttle crash, 9/11

In 1980s, creation of DMORT (Disaster Mortuary Operational Response Team). Allowed for dedicated personnel to aid in collection and identification of remains.

• Team of pathologists, anthropologists, odontologists, DNA techs, etc.

• Team that works with surviving family members to collect antemortem records important for identification efforts

What is trace evidence?

• Typically, invisible evidence that encompasses both personally identifying biological material (DNA or fingerprints) and other circumstantial nonbiological material.

• Biological trace evidence (DNA) is present 38% of cases

• Latent fingerprints are present in 28% of cases

• DNA is present in only 4.5% of homicide cases

• Hence, multiple materials and their analyses are incredibly important for solving criminal cases

Major types of trace evidence: Hair

• Postmortem hair banding (PMHB) occurs 2-3 days after death

• An opaque ellipsoidal band formed by gas/air pockets near the root of the hair

• Important if hairs with PMHB found in location, as it shows movement of body after death

• Hairs also contain DNA. In the follicle, blood-borne materials get incorporated into the hair matrix

• Nuclear DNA preserved in the hair follicle (individualizing), but only mtDNA is preserved in the grown-out hair shaft (not individualizing)

• In the case of forcibly removed hair, nuclear DNA is likely to be preserved. Naturally shed hair might also have it if the root is preserved

Major types of trace evidence: Bite marks

• Typically performed by forensic odontologists (forensic dentists) beginning in the 70s/80s

• From the victim, the following data are collected:

1. Demographics (age, sex, ethnicity)

2. Location of bite mark and surface contour

3. Bite mark shape (e.g., round, ovoid)

4. Color and size of markings

• Photos taken with and without flash and UV over 24 hr intervals due to visibility differences

Base layer of human skin contains melanin. Injury to the skin causes melanin to be released throughout the area. As it heals, cells (melaninocytes) migrate to edges of the wound.

Melanin absorbs UV radiation (think how different complexions tan differently) hence UV photography can capture these marks

• First 12 hours: high contrast and visibility

• Day 2: No bite marks discerned, only bruising, which persisted for 12 days. UV could not discern bite

• Day 17: Bitemark pattern reappeared in UV photographs

• Day 60: Bitemark pattern peaked in visibility

• Day 61+: Visibility decreased

• Dental impressions and saliva sample from a suspect are taken

• Look for any trace amounts of DNA in bite wound

• Look for idiosyncrasies of dentition, such as:

  • Canine-canine distance

  • Tooth alignment

  • Arch shape

  • Diastemas (gaps)

  • Dentistry work

  • Wear or chipping

Bite Mark Analysis drawbacks

• Has no solid scientific basis

• Unlike astrology, we can be fun, many negative consequences

Bite Mark Analysis vs. Forensic Odontology

Forensic Odontology: the broader study of human dental remains for forensic purposes

• History and appearance of dentition can be specific to the individual

History and appearance of dentition can be specific to the individual

• Orthodontic history or apparati

• Presence of fillings

• Idiosyncratic missing teeth

• Dental abnormalities

  • Supernumerary or missing teeth

• Dental staining or erosion patterns

• Can be very useful in identifying a decedent

Specific role of the forensic anthropologist

Frye and Daubert Hearings

• Either side may choose to challenge the credentials of a forensic anthropologist

• Occur pre-trial

Goal is probably to get the anthropologists testimony thrown out

• Remember – goal of prosecutor or defender is not to find truth, but to win for their side

Frye Hearings

Three foci

1. Whether the Forensic Anthropologist qualifies as an expert “by knowledge, skill, experience, training, or education,”

2. Whether the Forensic Anthropologist's “scientific, technical, or other specialized knowledge” will help the jury (or the judge) understand the evidence or determine a fact in issue

3. Whether the techniques employed by the Forensic Anthropologist are generally accepted as reliable in the scientific community

Daubert Hearings

Three foci

1. Whether the testimony is based on sufficient facts or data

2. Whether the testimony is the product of reliable principles and methods

3. Whether the Forensic Anthropologist has reliably applied the principles and methods to the facts of the cas

The Role of a Forensic Anthropology

Usually to provide expert testimony

• “An opinion stated under oath by a qualified individual during a trial or deposition. Such testimony can aid in clarifying complex concepts, presenting scientific evidence, evaluating data, and assisting in understanding the implications of certain actions or events.”

El Sendero Luminoso/The Shining Path

Founded 1969 by Abimael Guzmán (1934 – 2021)

• University philosophy prof.

• Heavy influenced by trip to Maoist China

Militant Maoist doctrine

• Believed success of communism required a military revolution

  • Elections rigged or unreliable

• 1977-1980: Began training camps in Ayacucho, Peru

May 17th, 1980 - ballot boxes in the town of Chuschi were burned

• Often considered inciting incident

• Violence & guerilla warfare escalated through 1981

Eventually, Peruvian government declared “emergency zone” in relevant regions

• Allowed military to act with arbitrary impunity

• Often led to murder, rape, abuse, and torture of innocent people

Military would train civilians to take action

• Responses to this from the shining path were brutal

• 70 killed in Lucanamarca Massacre

Rejected the concept of human rights:

• “Our position is very clear. We reject and condemn human rights because they are bourgeois, reactionary, counterrevolutionary rights, and are today a weapon of revisionists and imperialists, principally Yankee imperialists.”

  • Communist Party of Peru – Shining

Path, Sobre las Dos Colinas

Between 1980 and 2000:

• 70,000 people dead or missing

  • Unclear which are govt and which are insurgent

  • Both sides waged brutal war against civilians

• 600,000 displaced

  • Majority of shining path victims people outside of positions of power

  • Indigenous, young, women frequently victims

1990 – Alberto Fujimori comes to power as president

• 1992: responds with force to the shining path

  • Largely ended the shining path as an active threat

  • Also killed thousands of civilians

  • Forcible sterilized indigenous women

  • Enacted a coup d’état dismantling legislative and judicial power

2000 – Alberto Fujimori fled to Japan

• 2007: Eventually captured by Peruvians during a trip to Chile

• 2024: Died

Truth and Reconciliation Commission established in 2001

• Formal Organization charged with investigating and recommending reconciliation of human rights abuses

• The 2001 TRC of Peru was charged with investigating a wide variety of human rights abuses

Part of the charge: forensic exhumation, identification, and repatriation of remains of individuals killed and buried in clandestine/mass graves

• >2500 bodies found

• >1500 identified

• >1300 returned to families

Identification of individuals is an ongoing process

Biological profile can be very limited – at best you get..

• Sex

• Age

• Trauma

• Stature

• Pathology

• Weight

How to reconstruct mobility?

Oxygen isotope analysis

Different body parts “remodel” at different speeds

• Fastest: Hair, nails, skin

• Slowest: Bones

• Never: Dental enamel

Allows a reconstruction of where people lived during various aspects of the life course

• Can help reconstruct where victims may have been from

The forensic work on The Shining Path is still politically important

• Much of Keikio Fujimori’s support comes from goodwill generated by her father’s dismantling the Shining Path