Final answer:
The blow fly is commonly used to establish the time of death in forensic entomology by studying its life cycle.
Step-by-step explanation:
The blow fly is commonly used to establish the time of death in forensic entomology. This is because blow flies are among the first insects to colonize a dead body and their life cycle can be used to estimate the postmortem interval (PMI) - the time since death.
Blow flies have a rapid life cycle that consists of four stages: egg, larva (maggot), pupa, and adult. By studying the development of blow fly larvae found on a body, forensic scientists can approximate the time of death.
During the early stages of decomposition, blow fly eggs are laid on or near the body. The eggs hatch into larvae (maggots), which consume the decomposing tissue for several days. The larvae then enter the pupa stage, where they undergo metamorphosis before emerging as adult flies. The time it takes for blow flies to progress through these stages can be used to deduce the PMI.