Entomology

Question 1

What is forensic entomology?

Answer 1

the study of insects and other arthropods associated with legal issues

Question 2

What does entomology have a special emphasis on

Answer 2

determination of the post mortem interval

Question 3

How can you determine the PMI via larval development?

Answer 3

• blow flies are attracted to a corpse immediately after death and they will lay eggs
• maggots are our primary focus as these are immature blow flies
  1. identify oldest maggots
  2. measure temperature
  3. identify species

Question 4

What is critical for determining PMI via larval development?

Answer 4

• temperature recordings - will measure temperature of body, as well as any maggot masses present
• a data logger is often added at the scene to record temperatures for 3-5 days
• temperature data will also be collected from the nearest weather station

Question 4

How do you determine PMI using successional ecology?

Answer 4

• a body goes through rapid biological, chemical and physical changes after death
• body will attract a sequence of insects

Question 4

What can be collected from the body?

Answer 4

• eggs
• larvae
• pupae & puparia

Question 5

What is needed to transport insects to the lab?

Answer 5

• store them at their base temperature
• a suitable food source is needed for adults

Question 5

What are the lab conditions for fly rearing?

Answer 5

• stored in dark controlled environment until larvae reach feeding stage
• need 65% humidity
• rearing growth cabinets under similar natural conditions does not statistically alter duration of lifecycles

Question 5

Once specimens have been identified how do you calculate the PMI?

Answer 5

Insect development is influenced by temperature and environmental factors. Entomologists consider local temperature records and environmental conditions to calculate the accumulated degree days (ADD) required for insect development and compare to a data base

Question 5

What can accelerate development?

Answer 5

• increase in temperature increases metabolic rate, food consumption and assimilation
• drugs like morphine, heroine or cocaine can hastened the larval stage if maggots feed on flesh doped with drugs

Question 6

What is entomotoxicology?

Answer 6

a subdiscipline of forensic entomology concerned with detection of drugs and their influence on necrophagous insects