Forensic entomology. Forensic scientist using a light microscope to identify a fly found on the corpse of a murder victim. A camera attached to the microscope displays the image on the screen at right. Identification of the insects on a corpse can provide information on how long the body was dead before it was found. Different species of fly and other insect lay their eggs at different times, and their larvae feed on different tissues. By studying the insect population in a corpse, a very accurate time of death can be calculated, which is an important piece of information in helping to identify the killer.