Forensic Entomology

Forensic entomology is defined as the use of insects and other arthropods in medicolegal death investigations (45,80). The pathologist must be aware of the significance of insects on the body and can assist in their collection (49). The pathologist also documents findings relevant to the forensic entomologist (e.g., clothing, apparent injuries).

Flies (order Diptera; Calliphoridae, or blowflies) are among the first colonizers of a deceased individual (45). The maturation of these insects (egg-larva-pupa-adult insect) serves as a biological clock, 1 to 2 wk following death (45,49,80,81). Data regarding fly lifecycles in one area cannot necessarily be used in another region (45,80). The presence of ammonia-rich compounds and hydrogen sulfide are important stimulants for egg deposition (45). Diptera do not oviposit in mummified tissue, favoring moist tissue (45). Development during the larval stages is dependent on the temperature at the death

Forensic Entomology Artefacts

Fig. 40. Embalmed body. The deceased was described as "unsteady" on her feet. She was prescribed warfarin because of a previous diagnosis of pulmonary thromboembolism. She needed assistance walking when visiting a doctor a few days prior to her death. No contusions were visible on external examination by the coroner prior to embalming. The embalmer remarked that some bruises started to appear while perfusing the body. (A) At autopsy, numerous bruises were visible on the chest. (B) Large bruise, inner right arm.

Fig. 40. Embalmed body. The deceased was described as "unsteady" on her feet. She was prescribed warfarin because of a previous diagnosis of pulmonary thromboembolism. She needed assistance walking when visiting a doctor a few days prior to her death. No contusions were visible on external examination by the coroner prior to embalming. The embalmer remarked that some bruises started to appear while perfusing the body. (A) At autopsy, numerous bruises were visible on the chest. (B) Large bruise, inner right arm.

Fig. 41. Embalmed body. (A) Facial cosmetic had been applied. (B) Face wiped to reveal an abrasion on the left temple.

scene before the body was found (45,47,49,80). Eggs are first laid in the orifices or wounds of the corpse within seconds of death (Figs. 31, 42; refs. 45, 47, and 82).

Eggs, larvae, pupae, and adult flies are collected (80). Larvae are preserved in 10% formalin. Eggs and larvae are also placed in a specimen jar with a food source (e.g., liver, muscle from body), covered with gauze, and kept at ambient temperature and humidity.

Fig. 42. Fly eggs deposited in left nostril.

• Significance

° Larvae alter wounds (36,49,62). Masses of larvae on the skin can be a clue to a site of bleeding (49,82).

° Live maggots, in the absence of a dead body at a location, suggest that a corpse was present (49). The finding of human DNA in larvae indicates feeding on a human body (50).

° Toxicological analysis can be done on fly larvae and reflects use of drugs in the deceased (49,50).

° Refrigeration does not dampen feeding activity by larvae if maggot masses form (47,82). Temperatures within these masses range from 27 to 35°C (81 to 95°F [50]).

° Other insects (e.g., ants, cockroaches, beetles) can create artifactual injuries (Fig. 43;

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