Forensic Taphonomy Flashcards
(19 cards)
What is forensic taphonomy?
It investigates physical, chemical and biological processes of human and animal decomposition and associated evidence
What are the related disciplines of forensic taphonomy?
Decomposition chemistry, Botany and Palynology, Microbiology, Fibres and textiles, Pathology, Entomology and Archaeology and Anthropology
Define the term death
Irreversible cessation of circulation of blood in body or of all functions of the brain of a person. It is a process
What is cell death?
Body dies cell by cell
What is somatic death?
Brain death
What are the 5 stages of Decomposition?
Fresh, Bloating, Active decay, Advanced decay and Skeletonisation
What are the characteristics of fresh decomposition?
Immediately after death, bacteria feeds off of intestines outwards, (Autolysis )Self destruction of cells and tissue, loss on skin colour, marbling, blisters and skin slippage, greenish discolouration on abdomen. Liver, Algor and Rigor Mortis
What is Liver mortis?
Lividity or blanching, Accumulation of blood due to gravity, evident in 30mins-2 hrs and becomes fixed within 9-12 hrs
What is rigor mortis?
Chemical process causing rigidity in muscles, conversion of ATP to ADP and lactic acid-locking chemical bridges, breakdown of tissues (putrefaction) releases rigor, begins in face and travels down body, evident in 2-6 hrs and fully developed in 12hrs. Dissapears in 24-48 hrs
What is algor mortis?
Cooling of body temperature to equilibriate to surrounding temperature
What are the characteristics of Bloating?
Occurs 36-72 hrs after death, initiated by autolytic process, degradation of macromolecules, gas and fluid cause bloating, dark discolouration, fluid blisters, temperature increase, purging of fluids, distinctive odours, decomposition chemistry.
What is decomposition chemistry?
Carbs break down to sugars, fungi decomposes to organic acids, can decompose sugar to organic acids and further to water and co2, also produces alcohols and gases. Proteins are broken down by bacterial enxymes to amino acids, produces ammonia (deamination), biogenic amines(decarboxylation), Hydrogen sulphide (Desulfhydration) and lipids oxidise to aldehydes/ketones
What are volatile organic compounds?
Alcohols, carboxylic acids, aromatics, sulphides, aldehyes and ketones
What are the characteristics of Active decay?
Discoloured natural fluids and liquified tissue forced from orifices by internal gas build up. Breaking of skin, remains deflate
What is a cadaver decomposition island?
Muscus sheath froms around cadaver, bacterial and insect activity, incorporated into surrounding environments
What are the characteristics of Advanced decay?
Insect activity reduces, maggots migrate away from remains, soil changes in pH and death of vegetation
What are the characteristics of skeletonisation?
Disintegration of soft tissue, bone exposure, hard tissue remaining. Bare bones lose greasiness
What is the purpose of forensic taphonomy?
Estimate PMI,, Decomposition rates/patterns, Determine cause and manner of death, identify deceased and locate victim remains
What are the ways of preservation?
Mummification (dehydration of soft tissue, skin looks leathery), Mummification in peat (very acidic water environment, low temperature, no o2, Bones dissolve, skin and internal organs preserved), Burial with lime (highly alkaline, slow decompostion), Adicopere(moist environment, preserve soft tissue and organs), Fossilisation
