The Task Allocation Problem
Ant colonies face a challenge familiar to any organization: how to distribute workers across different tasks—foragers, patrollers, nest maintenance, midden workers, brood care. The proportions needed change constantly.
In human organizations, a manager would reassign workers. In ant colonies, no such manager exists.
Gordon's Discovery: Interaction Rates
Ants switch tasks based on the rate of interactions with other ants doing those tasks:
- An ant performing task A encounters other ants
- She detects their task by their odor
- If she frequently encounters ants doing task B, she may switch to task B
- If she rarely encounters ants doing task A, she may leave task A
Local encounter rates encode global demand.
Task Switching Thresholds
Not all ants are equally likely to switch. Ants have different thresholds:
- Some ants switch easily (low threshold)
- Some ants are stubborn (high threshold)
- This variation is crucial for colony stability
The mix creates stable yet adaptive behavior.
Application: Pheromone Sensitivity
Our agent castes implement this through the pheromone_sensitivity parameter:
- Scout (0.3) — Low sensitivity, explores despite signals
- Harvester (0.9) — High sensitivity, follows established paths
- Hybrid (0.5) — Adaptive, switches based on context
"The task an ant is performing depends not on any property of the individual ant, but on what the ant has experienced recently."