Chapter 11 Test Flashcards
Know the 5 stages of decomposition
Fresh, bloated, decay, active decay, dry
Know what the earliest cases of the use of insect evidence to solve crimes was
The washing away of wrongs Sung tz’u in 1247
Can insects that suck up liquids get nourishment from a dried decaying body in the later stages of decomp?
Yes
Do blowflies lay eggs at night?
No
Know Dr. David Hall
Studied the problem of flies feeding on living cattle and sheep. Reduced the damage and number of livestock deaths due to flies, blowflies of North America laid the groundwork for forensic entomologists
Know Bergeret D’arbois
French entomologist in 1855 first observed insect succession based on the body’s predictable physical and chemical changes. Estimated how a baby died in 1848 using this idea.
Know Jean Pierre Megnin
published further insect succession studies in 1894
On a decomposed body the feeding larvae may have human tissue stored in their crops that can be analyzed to determine what?
Identification of DNA of the body, toxins, poisons, and other drugs or substances
Blowflies also known as carrion flies or bottle flies include what
Bronze, blue, and green bottles
Within minutes of death odor emitted from a dead body can be detected by blowflies from what distance?
A mile
The blowfly lifecycle has 6 stages, how many larvae stages are included?
3
How many hours do blowfly eggs usually hatch?
8 hours
Know about flesh flies.
Medium-sized flies arrive within minutes of death, with black and gray longitudinal stripes on the thorax and a checkerboard abdomen. They deposit living larvae onto the flesh.
The arrival of which type of beetle is associated with the advanced stage of a dead body?
Hide beetle; sexton and hairy rove can appear in the advanced stage
What are coffin flies?
Small flies, the size of fruit flies, that can reach victims in concealed or wrapped
To provide the most accurate estimate of PMI at a crime scene, which type of larvae should be collected?
The oldest larvae
How do temperatures of feeding maggot masses compare to ambient temperatures?
It is 3 to 12 degrees C higher than the ambient surroundings
Environmental conditions affect the growth of larvae, consequently, in the collection of meteorological data, it is suggested that rainfall amounts be recorded for how long?
At least one month; 1-2 weeks before it disappears and 3-5 after the body was found
The number of hours at an adjusted average temperature, using Celsius degrees, that it takes an insect species to reach a particular stage of development is expressed how?
Accumulated degree hours
The lower limit threshold is the temperature below which growth and development ceas for an insect. For most insects what temperature represents their lower limit threshold?
10 degrees C
Know what a cadaver is
Dead body used for science
How many maggots need to be collected at a crime scene?
50 per mass
What are the 3 body segments of an insect?
Head, thorax, and abdomen
In what part of their anatomy do blowfly larvae breathe through?
The posterior
