ABSTRACT
Insects typically are the first organisms to discover a body after death. They are capable of arriving at and colonizing within minutes of the victim’s final breath (Anderson and VanLaerhoven 1996, Nuorteva 1977, Erzinclioglu 1983, Catts 1990, Catts and Goff 1992, Smeeton et al. 1984, Smith 1986, Dillon 1997, Wells and Lamotte 2001). As such, it is possible to infer a portion of the postmortem interval (PMI) from the age of the fly larvae that arose from the first eggs deposited on the body. The entomological basis for the postmortem interval estimation may also be referred to as the period of insect activity (PIA) or the time of colonization (TOC). When weather conditions are optimal and there are no extenuating circumstances preventing or delaying oviposi- tion, the minimum PMI (or PIA/TOC) is obtained with the assumption that flies did, 252indeed, deposit eggs very shortly after death. Age is derived by comparing the degree of development of maggots collected from a corpse with maggots of the same species reared under constant conditions (Kamal 1958, Nuorteva 1977, Smith 1986, Catts 1990). Development data are available for a number of forensic flies under a number of different temperature/relative humidity regimes (Kamal 1958, Ash and Greenberg 1975, Byrd and Butler 1996, 1997, Greenberg 1991, Grassberger and Reiter 2001, 2002, Anderson 2000b, Byrd and Allen 2001). Likewise, historical weather data at or near the location of the body can be obtained from the hundreds of weather stations placed throughout the United States (https://lwf.ncdc.noaa.gov). Insect development as an indicator for portions of the postmortem interval is most relevant when the victim has been dead only a short period of time, before the first wave of flies has left the corpse.
