Forensic Anthro - Lectures 1,2,+6

Four subdisciplines of Anthropology

• Cultural anthropology 

• Archaeology 

• Linguistics 

• Biological anthropology

Forensic Anthropology

the application of techniques and theories used in biological anthropology and bio-archaeology to address matters of legal and criminal concern (of medico-legal significance)   

When presented with an unknown individual, the forensic anthropologist will develop a biological profile.  

• Estimate of age-at-death 

• Estimate of sex 

• Estimate of stature 

• Estimate of ancestry 

“Father of Forensic Anthropology in the United States”

Thomas Dwight

1940s-1970s

• The development of forensic anthropological methods based on the skeletal remains of deceased soldiers (WWII and the Korean War) 

• Wilton Marion Krogma (1903-1987) wrote Guide to the Identification of Human Skeletal Material (1939) and The Human Skeleton in Forensic Medicine (1962) 

1970s-1990s

• Biological/physical anthropology becomes a part of the American Academy of Forensic Sciences in 1972, and the American Board of Forensic Anthropology is created in 1977 

• During this period, there was a significant increase in forensic anthropology research, employment, and acceptance by the wider forensic community.  

1990s-present

• The FBI Laboratory began sponsoring SCIENTIFIC WORKING GROUPS (SWG) in partnership with the National Institute of Justice (NIJ) to improve forensic practices and build consensus 

• SWGANTH formed in 2008 and is the SWG for Forensic Anthropology. Created to help standardize the use of forensic anthropology methods and establishing the best-practice principles 

• In 2015, the American Academy of Forensic Sciences developed the Academy Standards Board (ASB) The anthropology subcommittee within the ASB focuses on standards and guidelines related to the application of anthropological methods 

• In 2018, a professional journal, Forensic Anthropology, was created to discuss research, policy, and the application of forensic anthropology globally. 

Skeletal collections consist of skeletal remains of _____ individuals or from _____ context that can be used for study, teaching and research 

KNOWN

When developing new methods of analyzing and estimating identifying parameters for unknown skeletons, the use of known skeletal material is _______

essential

Key schools for Forensic Anthropology(top two)

• Forensic Anthropology Facility, University of Tennessee at Knoxville 

• Forensic Anthropology Center and Forensic Anthropology Research Facility at Texas State 

True or false: the skeleton represents evidence

true

Frye Rule(1923)

“General acceptance rule” - one of the first to address evidence admissibility. The US Supreme Court granted certiorari to determine the proper standard for admitting expert testimony of scientific knowledge.  

The Federal Rules of Evidence

govern the admissibility of expert witness testimony in federal trials in the US 

A _____ will determine whether the forensic anthropological evidence will be considered admissible in the trial  

judge

Bones in adults have these two basic structures

1)compact bone

2)spongy bone

the only difference between molecular and cellular compositions of compact and spongy bone tissue

porosity

cortical bone

solid, dense bone found in the walls of bones shafts and on external bone surfaces

trabecular or cancellous

more spongy, porous, lightweight, honeycomb structure found 1)under protuberances where tendons attach 2) vertebral bodies 3)ends of long bones 4)short bones 5)sandwiched within flat bones

diploe

cancellous/trabecular bone when in the cranial bones

medullary cavity

hollow inside the shaft of bones. The cavity is there to provide space for bone marrow within bone shafts

periosteum

a thin tissue layer covering the outer surfaces of bones

endosteum

inner surface cellular membrane that lines the inside of bone

The skeletal system consists of the ____ and _____ framework of the body

bony and cartilaginous

The skeletal system consists of the bony and cartilaginous framework of the body. The main functions are to:

-facilitate movement

-give support to soft tissues

-protect major organs + blood vessels

-provide stability for the body

-center for blood production

-act as an important reservoir for fat as well as calcium

osteo

bone

odonto

teeth

bone consists of two components: _____ and ______

mineral and organics

mineral=hydroxyapatite

(calcium phosphate molecule); what gives bone its strength and rigidity; 65% of the bone

organic = collagen

protein that gives bone a framework or scaffolding for the mineral part of the bone. Also gives bone a small amount of flexibility or elasticity. Reduces bone brittleness; 35% of the bone

The bones of our skeleton are ______. Bone is constantly ______ itself and a complete replacement of the bones of the skeleton takes ten years.

living organs; remodeling

osteoclast

bone cells (bone break down/resorption

osteoblasts

bone cells(bone building/mineralizing)

osteocytes

(mature osteoblasts) that become locked in the bone matrix when they become surrounded by the osteoid they secrete

osteoid

is the non-mineral, organic component of bone during formation(it will later mineralize)

osteoclasts and osteoblasts…

work together to remodel bone known as a basic multicellular unit

Remodeling process: activation

recruitment of precursor cells that will become osteoclasts. Converts a resting bone surface into an active one. Signals for activation include microcracks or hormonal changes

Remodeling process: resorption

osteoclasts break down bone in tunnel shapes through secreting demineralizing acids

Remodeling process: reversal

the switch between bone resorption to production, osteoclasts stop and osteoblasts start

Remodeling process: formation

osteoid is laid down by osteoblasts, filling in the tunnels made by osteoclasts

Remodeling process: mineralization

mineral is incorporated into the already laid down organic component

Remodeling process: quiescence

remodeling is complete for now. Osteoblasts either become osteocytes trapped in the bone matrix or are removed

Bone is a living tissue that needs to be able to receive nutrients, oxygen, and for waste to be removed. There is a ________ in bone to make this possible

system of canals

Haversian system

system of canals + passages with individual units within the system being called osteons(red box)

osteons

cylindrical structures that contain a mineral matrix and living osteocytes. Have canals that aligned parallel to the long axis of the bone. 

Lacunae

the space where osteocytes live

canaliculi

microscopic canals between the lacunae of ossified bone. The radiating processes of the osteocytes extend into the canaliculi, connecting osteocytes to each other

canaliculi allow for the exchange of ____, ______, and the removal of _____ products between osteocytes and blood vessels

oxygen;nutrients;waste

each osteon consists of _______which are….

lamellae; layers of compact matrix that surround a central canal called the Haversian canal

lamellae

plates of collagen fibers; surrounded by cementing mineralized bone matrix

volkmann’s canals(perpendicular)

provide energy and nourishing elements for osteons

at birth about _____ bones

270

a fully mature adult has ____ bones

206

trabecular bone grows where there is _________

red marrow, blood-forming tissue

modeling

sculpting of bones into their final adult shape

remodeling

process of bone turn over or replacement

ossification

the process of laying down new bone material by cells called osteoblasts

intramembranous ossification

ossification that occurs in the flat bones of the skull and the clavicles. Mineralization starts in a connective tissue membrane and then spreads

endochondral ossification

cartilage is the ossification precursor

woven bone

characterized by a haphazard organization of collagen fibers and is mechanically weak. Also forms at the sites of fracture.

lamellar bones

replaces woven bone and is the end point of bone growth whether cancellous/trabecular or compact/cortical.

forensic anthropology is interested in ____ human skeletal remains. determining this is known as establishing _______

recent; medicolegal significance

Three questions that must be answered in the affirmative(yes) for the material to be medicolegal significance…

1)Is the material skeleton(bone/teeth) vs some other non-skeletal material?

2)If it is bone/teeth, is the skeletal material human versus nonhuman in origin?

3)If it is human, is the human skeletal material recent vs nonrecent?

________ or _______ may damage bone morphological features, making assessing skeletal material difficult

taphonomy; deliberate alteration

taphonomy

what happens to a body between death and discovery

deliberate alteration

fire,acid,etc.

determining if it is bone or not bone?

-radiology(x-ray)

-histology(microscopic analysis)

-elemental analysis(calp concentrations[destructive not recommended])

-x-ray florescence(XRF [from handheld to synchrotron; non-destructive])

-alternate light source(ALS [collagen])

-scanning electron microscopy and (SEM/EDS)

determining if it is human or not human?

-proteomics, zooarchaeology by mass spectroscopy(ZooMs)

-histology(haversian system generally=human)

-DNA

Ways to tell the remains are not of medicolegal significance:

• no way to identify the person

• individual is from a time when the crime can’t be processed through criminal justice system

• no crime was committed in relation to the person’s death

recent bone may…

have soft tissue, may be greasy, may be an odor, may be insect activity

the ______ used to assess whether human remains are contemporary based on: _____, ____, _______

primary indicators; taphonomic; contextual; biocultural clues

Is the human bone archeological or contemporary?

-soft/connective tissue

-grave goods

-surgical implants

-radiocarbon date

-evidence of autopsy

-burial position

-modern dental work

-teaching skeleton

-dismemberment

-bone color

Even if found to not be bone or found to be non-human bone or found to be archaeological human bone, ________ that it is not of forensic interest

DOES NOT MEAN

True/false: even if bone is not human there may still be a crime and a need for forensic investigation(wildlife forensic case)

true

Archaeological human skeleton material may be ______ or ________ or ______

illegally excavated; disturbed during looting/grave robbing; hate crime