Assignment 831-W443




  1. Define forensic entomology

Itis the study and application of insects and other arthropods thatinhabit remains of decomposing nature to criminal matters. Arthropodsincluding millipedes, arachnids, crustaceans and centipedes are someof the arthropods that are applied in legal or criminal cases.

  1. Define postmortem interval

Itis defined as the time interval from death and corpse recovery.Forensic entomologists define PMI as the time interval from insectcolonization and the discovery of the body. Because the colonizing ofinsects takes place faster after death with time ranging from minutesto a few hours, calculation of PMI enables determination orestimation of the demise period.

  1. When would you expect Blow flies to arrive during the decomposition process?

Theblow flies visit the corpse at decomposition stage that begins at thetime of mortality. They are usually the first insects to visit abody. During this period, the body is intact, and the insect visitsthe corpse and starts to deposit eggs on regions with a mucousmembrane, for instance inside the ears and the eyes. Based on theweather conditions, the eggs forms the first instar. These arefollowed by a second and third instar if the weather conditionpermits( Apupa and finally an adult blowfly is formed if weather conditions arefavorable.

Variousinsects are attracted to the corpse at different specific stages ofdecomposition. New blow flies can never be found depositing theireggs after the initial time of death. Other insects such as the hidebeetles cannot be found at the beginning of the decomposition stagebecause they only attack the corpse at the very end of thedecomposition stages.

  1. Describe how you could determine whether a fly larva is a 2nd or 3rd instar?

Determinationof the worms age is through the counting of the spiracular slits onthe larvae tail. One more slit is added each time a larvae molts. A2ndinstar is determined if the larvae have two slits. Three slits on thetail of the larvae show that it is the 3rdinstar(