Forensic entomologists use their knowledge of insects and and their life cycles and behaviors to give them clues about a crime. Most insects used in forensic investigations are in two major orders: Diptera (flies) and Coleoptera (beetles).
Species succession may provide clues for investigators. Some insect species may feed on a fresh corpse, while another species may prefer to feed on one that has been dead for two weeks. Other insect species that prey on the insects feeding on the corpse may also be found.
Weather data is also an important tool in analyzing insect evidence from a corpse. Investigators will make note of the temperature of the air, ground surface, the interface area between the body and the ground, and the soil under the body as well as the temperature inside any maggot masses. They will also collect weather data related to daily temperature (highs/lows) and precipitation for a period of time before the body was discovered to the day the insect evidence was collected.
What two things about insects do forensic entomologists study?