Secondary Coloniser
Definition
A species that requires a chemical or physical change produced by primary colonisers before it can exploit the resource: cheese skippers attracted by butyric acid, or dermestids exploiting dry tissue left by blow fly larval consumption.
- Requirement
- Chemical or physical change made by a primary coloniser first
- Example species
- Cheese skippers, dermestid beetles
- Cheese skipper trigger
- Butyric acid produced during decomposition
- Dermestid resource
- Dry tissue left after blow fly larval feeding
- Field
- Forensic entomology, insect succession analysis
Common questions
How does the arrival of secondary colonisers help estimate postmortem interval?+
Because secondary colonisers only arrive once primary colonisers have altered the remains to the right stage, such as reaching the butyric fermentation stage or drying out tissue, their presence or absence brackets the decomposition stage the body has reached, adding a cross-check to the estimate derived from primary colonisers alone.
Why do dermestid beetles specifically favour dry, late-stage remains over fresh tissue?+
Dermestids specialize in keratin and dry protein, which is unsuitable for blow fly larvae that need moist tissue, so dermestids are physiologically adapted to exploit the desiccated skin, tendon, and hair left behind once earlier colonisers and general decay have removed the moisture and soft tissue.
Can secondary colonisers arrive on a body before primary colonisers have finished their work?+
Some overlap does occur at the margins between decomposition stages, but a secondary coloniser's larvae generally cannot establish and thrive until the specific chemical or physical condition it depends on, such as sufficient butyric acid or sufficiently dried tissue, is actually present, so true early arrival is limited.
Related terms
- Carrion Succession
- The predictable, roughly sequential replacement of insect communities on a decomposing body, driven by changing chemical substrate. Not a strict relay with...
- Faunal Assemblage
- The complete community of arthropod species present at a body at a given time. Comparing an observed assemblage against reference succession data...
- Primary Coloniser
- A species that exploits the body directly, typically arriving at or very soon after death, before decomposition has substantially modified the resource....
- Successional PMI Window
- The time range implied by knowing that the body is in a particular succession stage. Broader than a development-based estimate but extends...
- Tertiary Coloniser
- A predator or parasite that feeds on primary or secondary colonisers rather than directly on the body. Their presence on a corpse...