Base Temperature
Definition
The species-specific temperature below which development effectively ceases. For most forensically relevant blow fly species this is in the range of 2-10 degrees Celsius; ADH accumulates only above this threshold.
- Definition
- Species-specific minimum for development
- Typical range
- 2 to 10 degrees Celsius for common blow flies
- Used in
- Accumulated degree hour (ADH) calculations
- Relation to development
- ADH accrues only above this value
Common questions
How is base temperature different from base (lower developmental) threshold?+
They describe the same underlying concept, the minimum temperature at which a species develops, but base temperature is the term more commonly used in the degree-day and degree-hour accumulation literature specifically, while base threshold is used more generally in insect development discussions.
What happens to a PMI estimate if the wrong base temperature is used?+
Because ADH sums only the temperature above the base value, a base temperature set too low overstates accumulated development and a value set too high understates it, so either error shifts the estimated time since colonisation and the resulting minimum postmortem interval.
Related terms
- Accumulated Degree Hours (ADH)
- A temperature-corrected measure of developmental time. Calculated by summing (hourly ambient temperature minus the species-specific base temperature threshold) across the period of...
- Instar
- A developmental stage between moults (ecdysis). Blow flies have three larval instars (L1, L2, L3), each ending when the larva sheds its...
- Posterior Spiracles
- The paired breathing openings at the hind end of a blow fly larva. Their slit count and sclerotisation state are the primary...
- Ptilinum
- An inflatable frontal sac on the newly eclosed adult blow fly, used to burst through the puparial operculum and push through soil....
- Pupariation
- The process by which the third-instar larva contracts and hardens its own cuticle to form the puparial case (puparium) that encloses the...