Colonisation Interval
Definition
The elapsed time since the first insect colonised the body. Often shorter than the PMI if access was delayed by concealment. An entomologist estimates a minimum colonisation interval; the PMI can only be stated as at least that long, potentially much longer.
- Field
- Entomological PMI estimation
- Definition basis
- Time since first insect colonisation, not death
- Relationship to PMI
- Often shorter than true PMI
- Reported as
- A minimum, not an exact value
Common questions
Why do entomologists report a minimum rather than a precise colonisation interval?+
Development data give a reliable estimate of how long insects have been feeding, but nothing in the insect evidence can prove how long the body sat before colonisation began, so the entomologist can only state that death occurred at least that long ago.
What scene factors most commonly cause a large gap between colonisation interval and true PMI?+
Concealment such as burial, wrapping, vehicle trunks, or enclosed buildings delays fly access the most, along with cold weather that suppresses fly activity, both of which can make the true PMI substantially longer than the colonisation interval alone would suggest.
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...
- Entomotoxicology
- The analysis of insect tissue for drugs and toxins when decomposition has made conventional biological fluids unavailable. Blow-fly larvae feeding on a...
- Maggot-Mass Thermogenesis
- The elevation of temperature within a dense larval aggregation by the combined metabolic heat of thousands of larvae. Documented elevations range from...
- Minimum PMI (PMImin)
- The shortest interval consistent with the entomological evidence. In practice this is what entomologists estimate: a floor on elapsed time based on...
- Thermal Bias
- Systematic under- or over-estimation of developmental temperature caused by using distant weather-station data, solar radiation on an exposed body, or micro-environmental features...