1. Forensic Taphonomy Flashcards
What does a medico-legal investigation involve?
Cause and manner of death
Individual’s biological and social identity
Time of death
What is the role of the forensic anthropologist in medico-legal investigations?
Discriminate postmortem changes from perimortem trauma or antemortem characteristics/trauma
Define taphonomy
Study of the processes by which organic remains pass from the biosphere into the lithosphere
What does a palaeontologist do?
Explain fossilisation and preservation in the geological record
Look at the whole time period: life-death-preservation
What are the 2 stages of taphonomy?
Biostratinomy - occurs between the death of an organism and its final burial
Diagenesis - occurs between final burial and recovery
What occurs during biostratinomy?
Disarticulation, dispersal, accumulation, fossilisation and mechanical alteration
Disarticulation
Occurs when decomposition causes the loss of soft tissue so bones are no longer held together
Dispersal
Separation of bones by natural events incl. water, scavenging etc
Accumulation
Occurs when there is a gathering of this same organic matter in one place caused by scavenging or humans
Fossilisation
Mineral rich water permeates organic material creating a fossil
Mechanical alteration
Processes that physically alter the remains e.g. freeze/thaw, burial, transport etc
What questions were raised from the Green River Murders (Gary Ridgeway 1980-2001)?
Distinguishing marks of scavenging from other marks on bone
Disarticulation patterns
Scavenger modification of soft tissue
What has a rise in taphonomy in forensic investigation caused?
Forensic anthropologist has greater scene presence and has helped to interpret evidence beyond biological parameters
What are the cross overs between traditional taphonomy and forensic taphonomy?
Determination of factors which cause destruction or damage to bone
Understanding how remains can move/change/be altered over time
Recognising and understanding human vs non-human causes of bone modification
What are the biggest differences between traditional taphonomy and forensic taphonomy?
Due to time line - forensic investigation is also interested in soft tissue
- changes
- decomposition
- modification
- disarticulation
- dispersal
- accumulations
What does Gifford (1981) say taphonomy should give us?
1 - scientifically grounded estimates of postmortem interval based on decomposition factors, entomological evidence, chemical methods, associated physical evidence modification
2 - reconstructions of the original position and orientation of the body
3 - characterisations of the role played by human intervention on the remains by “stripping away” all other “natural” agents affecting them
Why taphonomy so complex?
Large number of factors have to be taken into account at each scene and their interactions with eachother and the body
Each factor witll change over time and the influence of each factor will change according to the state of the body
Must have an understanding of the sequence and appearance of different factor and their relationships with eachother
How are the complex factors grouped?
Environmental factors = external variables (climate - abiotic, organic - biotic)
Individual factors = those the subject themselves bring to decomposition process
Cultural factors = human mortuary activities, embalming, trauma caused by assailant
= 3 way interaction of remains, victim and environment
Why do we need an understanding of taphonomy?
Time since death
Differentiating primary and secondary deposition sites
Correct interpretation of bone markings
Maximise recovery of remains
Explain positioning/damage as human/non-human
What are the 4 time periods taphonomy is interested in?
1 - antemortem period - just prior to death/deposition
2 - perimortem period - around time of death/deposition
3 - postmortem period - deposition to recovery
4 - post recovery period - recovery to analysis
What questions must be asked to interpret the scene?
Has the scene changed?
Is it the same as where death occurred? (primary deposition)
Is it different from where death occurred? (secondary deposition)
What was the scene like when the body was deposited?
Has the presence of the body made any difference to the scene?
What needs to be considered when a body is on the surface?
type of surface urban/rural water vegetation animals time of year time since deposition
What needs to be considered when a body is in water?
salt/fresh tidal/still depth temperature machinery water creatures
What needs to be considered when a body is buried?
soil depth point of deposition vegetation machinery drainage land use animals time of year
What needs to be considered when remains are moved?
Movement on surface/water or in burial environment? When did it occur? Why did it occur? Who caused it? What does this mean for recovery?
What needs to be considered when bone is damaged?
Must be able to recognise normal bone morphology
Understand damage caused by animals - which animals can damage bone and how?
Understand damage caused by environment/weathering/burial environments
What difference has the environment made to analysis of the damage?
What about the body itself must be taken into account?
Size Age Clothing/wrapping Injuries Deposition Movement
What are some research areas among forensic taphonomy?
Grave deposits Decomposition and transport in water Mass graves Mass disaster taphonomy Degradation of clothing Fatal fires Pig scavenging Environmental effects
What are some problems with taphonomic research?
Inclination to presume no soft tissue N=1 Reconstructed over long time periods Minimal human interventions Localised Impossible to 'control' factors Use of human analogues Act of researching itself causes changes to the environment
How did bon Bertalanffy (1949) define equifinality?
“reaching the same final state from different initial states” in an open system, one capable of “exchanging materials with its environment”
e.g. reaching the same final state from different initial conditions and in different ways
