The Postmortem Interval

Question 1

What does decomposition include?

Answer 1

loss of skin, muscle, internal organs, and other body components

Question 2

TRUE or FALSE: decomposition continues until there is NOTHING left

Answer 2

true

Question 3

When is estimating time since death most accurate?

Answer 3

within the first 24 hours

Question 4

Livor mortis

Answer 4

the cooling of the blood after death

Question 5

Algor mortis

Answer 5

body temperature moves towards ambient temperature

Question 6

Rigor mortis

Answer 6

as muscle breaks down, they release a chemical that causes them to tense up

Question 7

Changes in vitreous humor

Answer 7

eyeball fluid (really resilient to decomposition)

Question 8

Forensic taphonomy

Answer 8

the study of what happens to bodies from the time they are deposited to when they are found

Question 9

What are the four topics of PMI?

Answer 9

1. process of decomposition 2. schedules of decomposition 3. timetables of animal scavenging 4. methods of specialists in other fields

Question 10

Autolysis

Answer 10

digestive fluids start digesting the body until they are all used up

Question 11

Putrefaction

Answer 11

gut bacteria start eating other parts of the body and produce a gas that causes blotaing

Question 12

How do insects impact decomposition?

Answer 12

flies and beetles use decomposition as an easy food source

Question 13

How do scavengers impact decomposition?

Answer 13

dismember, damage, scatter around, and expose the body to the elements

Question 14

How does plant activity impact decomposition?

Answer 14

roots grow towards good nutrients (ex. root etching)

Question 15

How was ground water impact decomposition?

Answer 15

it contains sediments than can mineralize bone

Question 16

How does fire impact decomposition

Answer 16

heat! dries out the body really fast and removes organics

Question 17

How does the sun impact decomposition?

Answer 17

rapidy dries out exposed side

Question 18

How does wind impact decomposition?

Answer 18

carries particles away

Question 19

How does water impact decomposition? (two ways)

Answer 19

moving bodies of water can push it into things; adipocere (fat & water) can create a little protective layer

Question 20

TRUE or FALSE: warmer weather leads to slower decomposition

Answer 20

FALSE

Question 21

Cycles of ____ and ____ disrupt connective tissue and cause the body to break down faster.

Answer 21

freezing; thawing

Question 22

____ humidity softens the soft tissue and increases decomposition.

Answer 22

high

Question 23

TRUE or FALSE: Decomposition is continuous, not finite.

Answer 23

TRUE

Question 24

What did the Anthropology Research Facility in UTK discover?

Answer 24

Within a year, bodies and warm and moist environments are fully skeletonized.

Question 25

What did researchers in Arizona discover?

Answer 25

Bodies in hot and dry environments become skeletonized anywhere from nine months to three years.

Question 26

What did researchers in Canada discover?

Answer 26

Bodies in cold climates take anywhere from two months to eight years to completely skeletonize.

Question 27

Why are buried and submerged remains difficult to research?

Answer 27

you have to dig up the body in order to observe the effects

Question 28

What did Rodrigues and Bass discover about submerged remains? (ratio)

Answer 28

1 week on the surface = 2 weeks underwater = 8 weeks underground

Question 29

What did William Haglund discover about animal scavenging?

Answer 29

the longer the postmortem interval, the fewer the number of bones recovered

Question 30

What is the most common insect used to estimate PMI?

Answer 30

the blowfly

Question 31

TRUE or FALSE: adult blowflies are counted in order to estimate PMI

Answer 31

FALSE

Question 32

When does estimation with blowflies become inaccurate?

Answer 32

after the appearance of pupa casings as that indicates multiple generations have passed

Question 33

What is the PMI if there are only flies?

Answer 33

less than 3 days

Question 34

What is the PMI if there are mainly flies?

Answer 34

3-13 days

Question 35

What is the PMI if there is an equal number flies and beetles?

Answer 35

13-25 days

Question 36

What is the PMI if there are only beetles?

Answer 36

25+ days

Question 37

What is the independent method of forensic botany?

Answer 37

estimating time since death by examining the rings of plant stems and roots

Question 38

What is the comparative method of forensic botany?

Answer 38

estimating time since death by comparing nearby plant growth to farther away plants

Question 39

What are the limits of forensic botany?

Answer 39

can only estimate PMI for individuals who died over a year ago and only in year long chunks