Entomological evidence helps narrow down time of death by analyzing growth stages in relation to ambient temperatures. What is this relationship commonly quantified as?

• A. Degree days
• B. Growing degree days
• C. Humidity index
• D. Decomposition rate factor

Answer: (B)

In forensic entomology, insect development is driven by heat; the time since death is estimated by how much heat the environment has provided during the period of development. The best way to quantify that is growing degree days, which measure accumulated warmth above a species-specific base temperature that drives growth. You calculate daily heat units by taking the average of the day’s high and low temperatures (or the average temperature) and subtracting the base temperature; if this result is negative, you add zero for that day. Summing these units over time gives the growing degree days, which correlates with the insect’s developmental progress and helps pinpoint the time of death. The other terms don’t capture this temperature-driven growth concept: a general “degree days” term is less specific to biological growth, humidity index relates to moisture rather than development, and a decomposition rate factor isn’t a standard measure of insect growth tied to heat.