Postmortem Changes to Bone

Question 1

What are the three things that usually cause postmortem changes?

Answer 1

dismemberment, taphonomy, fire

Question 2

What are the reasons for dismemberment?

Answer 2

1. impede identification (remove hands, bash face)
2. lack of respect/hatred for decedent
3. easier to transport/hide

Question 3

What are the three instruments that generally cause dismemberment?

Answer 3

cutting, chopping, and chiseling instruments

Question 4

What are the two types of dismemberment?

Answer 4

localized dismemberments and generalized dismemberments

Question 5

Localized dismemberments

Answer 5

specific regions dismembered

Question 6

Generalized dismemberments

Answer 6

across entire body or in logical locations

Question 7

Why are saws similar to chisels?

Answer 7

the teeth act like individual chisels

Question 8

Crosscut saws

Answer 8

saw across grain of wood; have angled tip

Question 9

Rip saws

Answer 9

saw with grain of wood

Question 10

What are the three types of marks caused by saws on bone?

Answer 10

1. superficial false start
2. false start kerfs
3. sectioned bone cuts

Question 11

Superficiale false starts

Answer 11

barely nicked it, startled by bone

Question 12

False start kurfs

Answer 12

metal wiggles and slips, common with handsaws

Question 13

Sectioned bone cuts

Answer 13

when the cut goes all the way through, useful in determining blade construction and saw type

Question 14

Kerf

Answer 14

cut marks made by saw

Question 15

Fine striations indicate

Answer 15

small teeth

Question 16

Deeper striations indicate

Answer 16

larger deeth

Question 17

Regular striations indicate

Answer 17

power saw

Question 18

Irregular striations indicate

Answer 18

handsaw

Question 19

Rough kerf floor indicate

Answer 19

fewer teeth

Question 20

Smooth kerf floor indicate

Answer 20

more teeth

Question 21

Breakaway spur

Answer 21

forms when you saw through most and the last bit snaps off, shows top to bottom motion of saw

Question 22

TPI

Answer 22

entire teeth per inch

Question 23

PPI

Answer 23

points per inch

Question 24

Are serrated knives considered saws?

Answer 24

Yes

Question 25

What are the three components of saw mark analysis?

Answer 25

full description of cuts, direction of saw cuts, and type of tool

Question 26

What are the three ways animal scavenging can impact remains?

Answer 26

scatter skeleton, break bones by trampling, remove bone segments by chewing

Question 27

What are the most typical carnivores involved in scavenging?

Answer 27

dogs and coyotes

Question 28

Punctures

Answer 28

small holes created by carnivore teeth, not fracture lines

Question 29

Pits

Answer 29

similar to punctures, but don't penetrate the cortical surface (from carrying bone)

Question 30

Scoring

Answer 30

scratches that usually appear as parallel lines (from nails/claws)

Question 31

Furrows

Answer 31

deeper than scorring, occur at ends of bones

Question 32

Bones that are ____ to detach are usually taken first.

Answer 32

easy

Question 33

Do scavengers usually take the cranium?

Answer 33

No

Question 34

Why do rodents get involved in scavenging?

Answer 34

rodents chew on bones to keep their teeth worn down (and for calcium)

Question 35

What marks do rodents leave on bones?

Answer 35

flat, square, parallel grooves

Question 36

What are the signs of weathering?

Answer 36

cracks, peeling and flaking, bone warping, bone bleaching

Question 37

What effects does the burial have on remains?

Answer 37

cracking/warping (soil weight) and erosion of cortical bone (pH, wind).

Question 38

Can water damage occur in all bodies of water?

Answer 38

Yes

Question 39

When can water damage occur?

Answer 39

when the body is moved, when putrefaction/bloating occurs, when individual bones are removed

Question 40

What does water damage the body through?

Answer 40

hitting rocks, disarticulation, algae straining, or hardening by silt