Forensic Taphonomy

Question 1

What are postmortem changes?

Answer 1

• losing bones
• parts of bone
• cracks
• pits and marks
• modifications to the bone shape

Question 2

What 3 major effects of animal scavenging on bone?

Answer 2

1. scatter and disarticulate remains (pulls limbs apart)
2. gnaw epiphyses (for nutritious red marrow)
3. break bones by trampling/chewing

Question 3

How do rodents attack bone?

Answer 3

• chew on cortical bone to wear down their incisors (perpetually growing)
• parallel marks/striations
• one can identify what kind of rodent by the size of incisors

Question 4

What is the carnivore dismemberment sequence?

Answer 4

1. soft tissues of head and neck
2. ventral thorax opened and contents of stomach and chest eaten > sternum & rib ends (cartilage)
3. upper limbs, scapulae and clavicles are separated from thorax
4. lower limbs removed from pelvis
5. thorax removed from area of disposal
6. long bones separated from eachother > ends chewed
7. all bones disarticulated, scattered, chewed

Question 5

How do humans dismember?

Answer 5

• humans don’t remove scapulae and clavicles, just humerus
• don’t remove femur from hip socket, just cut through femur instead
• don’t separate parts of thorax > intact

Question 6

What are signs of carnivores on bones?

Answer 6

• puncture marks (completely through) and pits (shallow depression)
• scoring (smaller marks)
• furrows (deeper lines, random)
• V-shaped depressions on diaphysis
• complete chewing of epiphyses to get marrow
• fracturing, splintering (to get to medullar cavity, yellow marrow)
• depressed fracture (collapse of cortical and trabecular bone)

Question 7

What is the postmortem interval?

Answer 7

how long an individual has been dead

Question 8

What is weathering?

Answer 8

when a bone is on the surface and exposed to uv radiation > bone shrinks and bleaches

Question 9

What is root etching?

Answer 9

• acidic substance secretd by roots that eat away the bone where bone and root are in contact
• causes erosion of cortical bone

Question 10

What are the 3 phases of water transport of a body?

Answer 10

1. body will sink and travel from initial dumping point
2. body floats and rises to surface where it travels even further
3. independent movement of individual body parts

Question 11

What are consequences of water damage?

Answer 11

• Perforation, destruction of bones (marine life, sea bed obstacles)
• Abrasion/ water rolling
• Loss of articulating bones
• Algae staining (algae growth of bones that have been down for a while)
• Hardening of silt forming crust on bone surface (eg. Sea foam)
• Deposition of aquatic insects (laying eggs in cavities, fossa, foramen)

Question 12

Describe how the body sinks and travels from initial dumping ground?

Answer 12

• air escapes lungs and body sinks
• as it sinks it scrapes and bumps across riverbed/ocean floor
• movement influenced by currents/eddies

Question 13

Explain how the body floats and rises to the surface where it travels even further?

Answer 13

• as it decays it fills with gases > floats
• digestive enzyme start travelling down the body > digests itself> breaks down tissue in rest of body
• body parts start separating (skull, hands, etc)

Question 14

Explain how independent movement of individual body parts happens

Answer 14

• round parts can travel long distances (skull)
• flat bones stay closer to point of insertion
• parts can travel 80+ km depending on conditions
• sea life and water break down the body