Death & Decomposition Part II Review: Why is TSD/PMI so important? Review: What happens in the Fresh (1st) Stage of Decomposition? STAGE 2: Bloat ⦿ 0-10 days ⦿ Putrefaction: bacterially-induced destruction of soft tissue and gas formation › Skin blisters and marbling › Build-up of fluids from ruptured cells and intestines Putrefaction – the gross stuff ➢ Decomposition that occurs as a result of bacteria and other microorganisms ➢ Results in gradual dissolution of solid tissue into gases and liquids, and salts Putrefaction ➢ Characteristics: ○ Greenish discoloration ○ Darkening of the face ○ Bloating and formation of liquid or gas-filled blisters ○ Skin slippage Putrefaction ➢ Begins about 36 hours after death ➢ Further destruction is caused by maggots and insects ➢ Above 40 F, insects will feed until the body is skeletonized Influences of Putrefaction ➢ Heavy clothing and other coverings speed up the process by holding in body heat ➢ Injuries to the body surface promote putrefaction ○ provide portals of entry for bacteria Marbling Stage 3: Active Decay ➢ 10-20 days after death ➢ Body begins to collapse and black surfaces are exposed ➢ Bloated body collapses and leaves a flattened body ➢ Body fluids drain from body Active Decay Active Decay: Destruction of Tissue • Severe decomp can result in complete destruction of soft tissue Active Decay: Advanced Decomposition Stage 4: Dry Decay ➢ 20-365 days after death ➢ Remaining flesh on body is removed and body dries out ➢ Body is dry and continues to decay very slowly due to lack of moisture ➢ Mostly reduced to hair and bones ➢ Skeletonization Dry Decay Dry Decay “Bonus Items” ⦿ Adipocere › Waxy substance created from fat › Not useful for time since death, but can help preserve a body longer ⦿ Mummification › Environmentally or culturally specific › Useful for extended preservation Adipocere – “Wax Mummy” Mummification Mummification The Body Farm THE BODY FARM ⦿ PRIMARY GOAL: To understand the processes & timetable of postmortem decay, primarily to improve determining the "time since death“ ⦿ The Body Farm is a simulation of various crime scenes using real human bodies. THE BODY FARM ⦿ Used by › Law Enforcement › Medical Examiners › Entomologists › Cadaver Dogs › Anthropologists › FBI for Crime Scene Training. ⦿ Use unclaimed cadavers & volunteers (who donate their body to science after death) THE BODY FARM ⦿ Only a few Facilities in the U.S. › Univ. of Tennessee (original) › Western Carolina University › Texas State › Sam Houston, TX Types of Research How does the decomp rate compare in: ➢ sunshine vs shade? ➢ In cool weather vs hot weather? ➢ In a shallow grave vs on the ground? ➢ In water? ➢ Inside a car? ➢ What effect do other variables have— humidity, insect activity, clothing, body weight, and so on? Doorway to death, the main gate of the Anthropology Research Facility—the “Body Farm”—consists of a wooden privacy fence inside a chain-link fence that’s topped with razor wire. One research study examined the effects of the elevated temperatures—and limited insect access—to which a body in a car would be subjected. Corpse 1-81 was an elderly white male; he became part of a pioneering study of insect activity in human corpses. After only a few weeks in the Tennessee summer, the skull is completely bare & many vertebrae are exposed. Close-up of a human femur & hip bone, containing an artificial hip implant. An aerial view of the Body Farm, taken from Patricia Cornwell’s helicopter. The large wooden tripods are used for hoisting & weighing bodies as part of a research study of weight loss during decomposition. A jaw from a research subject held by the founder of the Body Farm. Climate’s effect on Decomp ⦿ Is the Body Farm a good standard for forensic scientists everywhere? › Why or why not? ⦿ Will there be differences in tropical environments? ⦿ What about deserts? ⦿ And cold climates? Arizona Desert – How does this compare to TN? Stage Description Time Fresh No skin 1-7 days discoloration, insect activity Early Decomp. Green to black 2-8 days; up to 4 discoloration, some months skin slippage, body bloated or deflated Advanced Decomp. Loss of internal 10 wks – 4 months; organs, caving of up to 3 years abdomen, mummified outer tissue, less (found to be 5x faster than half skeleton in summer) apparent Skeletonization More than half of 3 months – over 3 skeleton exposed years Extreme Decomp. Beginning breakdown 9 months – over 3 of bones years Western Canada – How does this compare? Stage Description Time Moderate Partial exposure 3.5 months or Decomp. of bone, loss of less some body parts Advanced Loss of internal 1.5 months – Decomp. organs, moderate 2.7 years bone exposure Skeletonization Majority of 4 months – 3.5 skeleton exposed years.