Forensic Entomology Flashcards
entomology
the study of insects
insect characteristics
- 3 tagmata
- large compound
- 3 pairs of legs on the thorax
- 2 pairs of wings on the thorax
- antennae
forensic entomology
any intersection between insects and the law
subfields for forensic entomology
- stored product
- urban entomology
- medicolegal
stored product
insects infesting food stuffs
an expert in stored product forensic entomology could answer:
- type of insect
- when/where the infestation likely occurs
- who is at fault
urban entomology
insects that affect people and their property
medicolegal
focus on necrophagous insects that typically infest/colonize human remains
forensic entomologist can help determine:
- postmortem corpse movement
- victim identification
- aspects of toxicology
- issues of neglect
- ID possible traumas
- estimate time since death
earliest arrivers to corpses
- most commonly used in forensic analysis
- flies arrive to lay eggs/larvae, eat, and mate
- adults/larvae eat soft tissue
highs of oviposit
eggs use less energy to hold and deposit
lows of oviposit
eggs have no method of defense
highs of larviposit
- larvae takes less time to develop
- they come out ready to eat
lows of larviposit
- less babies
- big energy investment for mom
secondary arrivers
- predators
- eat tissue and oviposit
late arrivers
progeny eat non-soft tissue (persist longer)
insect succession
the change in carrion insects present on a corpse over time
forensic use of insect succession
- community composition can be used to estimate a minimum and maximum PMI
- collect taxa from corpse
- compare taxa to different timetables
why use pigs as surrogates for human decomposition?
- easier to get than humans
- easier to place
- corpse size similar to humans
- hairless
how quickly will blow flies get to a corpse? oviposit?
- corpse: 30 sec to minutes
- oviposit: 1 hr to a few hours
what will decay insects arriving?
- weather
- location
- fire
- body movement
indication of perimortem trauma
insects have a characteristics pattern of oviposition on a corpse
where are eggs laid?
- orifices first
- laid in moist folds
- laid where skin contacts the ground
migrating third instar maggots
- after getting enough nutrition to go through metamorphosis a maggot will migrate away from the body
- many times mass exodus
where to find migrating third instar maggots
- look in loose soil/ leaf litter
- look at the edges of a room or underneath items in contact with the ground