Final answer:
Flies typically begin laying eggs on a body within 20-30 minutes after death. Forensic entomology can help determine the time of death based on the stages and type of maggots found on a body.
Step-by-step explanation:
Flies typically begin laying eggs on a body within 20-30 minutes after death. They are attracted to dead animals because they lay their eggs on them and their maggots feed on the decaying flesh. This process is known as forensic entomology and can be used to determine the time of death.