Ant Trails
A small agent simulation. Each ant follows a few local rules — follow scent, carry food home, leave scent on the way — and trails appear without any ant planning them.
Watch simple ants find food and lay scent trails — then change the map and the evaporation and compare.
FreeOn this device
Cursor: column 33, row 21 — scent 0.00. Blue square nest, amber food, grey walls, white ants (yellow when carrying).
An illustrative model with made-up rules — not a description of how real ants behave.
Controls
- Play, Pause and Step run the colony; Restart starts the current map again.
- Choose Nest, Food, Wall or Erase and tap the map — or Tab to the map, move the cursor with the arrow keys and press Enter. Editing pauses and restarts the run.
- Evaporation sets how fast scent fades. Compare runs the same seed at two rates and charts deliveries.
The rules
- Each tick an ant chooses between the free cells ahead, ahead-left and ahead-right, favouring stronger scent; one time in ten it picks at random.
- An ant carrying food also leans towards the nest and leaves scent behind it. Food is taken one unit at a time and delivered once at the nest.
- Scent fades by the evaporation rate every tick and 5% spreads to each side neighbour. It never goes below zero or into walls.
Scoring, saving and limits
No score. The status line counts deliveries; the chart compares two settings on the same seed.
Your map and evaporation setting are kept on this device. A run itself restarts on reload — the same map and settings replay identically.
An illustrative model with invented rules, not a claim about real ant behaviour. At most 200 ants. The Empty larder scenario has no food on purpose: the ants simply explore.
Questions
- Why do trails form at all?
- Ants returning with food leave scent, and other ants prefer stronger scent, so a successful route gets reinforced while unused ones fade.
- What does evaporation change?
- Slow evaporation keeps old trails around longer (sometimes too long); fast evaporation makes the colony forget quickly.
- Is it random?
- Each scenario has a fixed seed, so a run is repeatable — change a setting and you see only the effect of that change.