Collecting & Preserving at scene, by non-entomologists
Investigators do not disturb insects limit # of people near body easy to disturb evidence begin several feet from body determine types of insects and development stages
measure distances from body assess current weather data check weather at scene & days before discovery collect samples of all insect stages on, near, under body at lab, raise insects under conditions similar to death scene
temp, humidity, precipitation, light, wind windows, doors - open or closed? - all affect progress of life cycle and PMI calculations
completes a forensic entomology data form - insect #s and types - body positions - location of eggs, larvae, and pupae on body - other insects, opportunistic feeders - insect movements - natural & artificial influences
Factors Affecting Insect Activity 4 habitats: 1. Natural environment & natural light 2. Natural environment & artificial light 3. Artificial environment & natural light 4. Artificial environment & artificial light
Factors Affecting Insect Activity higher temp, faster metamorphosis so, need several temp readings: 1. ambient air (1 ft and 4 ft above body) 2. soil (surface, 10 cm & 20 cm below surface) 3. center of infestation
Collection special techniques and materials nets, jars, ethyl acetate to kill flies pinned or preserved with 80% alcohol, 20% water solution preserve eggs & larvae vials - case #, collection time, date, geographic location, location of insects on body, investigator's initials - 2 labels