Your browser blocked the live colony. The idea holds anyway: scent laid down, scent evaporating, and the shortest path surviving the difference.
FORMICARY
Two hundred ants, no plan between them. Watch the shortest route from nest to seed brighten out of nothing but scent and time.
Click or drag on the field. Crumb piles run out; the trail to a spent pile fades on its own.
No architect. No blueprint. The path draws itself.
A single ant is nearly blind and remembers almost nothing. Put two hundred of them between a nest and a seed and a road appears — not because anyone planned it, but because scent on a shorter route is refreshed faster than it can evaporate. That is stigmergy: coordination through the trace left in the environment, never through instruction.
Four rules, no fifth
The whole mechanismLay
Every ant dribbles scent as it walks — home-scent on the way out, food-scent on the way back. It never chooses a destination; it just marks where it has been.
Evaporate
Scent fades by the second. A trail that nobody re-walks is gone within a minute — the field is constantly forgetting.
Reinforce
A shorter round trip finishes sooner, so its scent gets topped up more often than it fades. Traffic and freshness feed each other.
Emerge
Longer detours starve for want of traffic. What survives is, by construction, close to the shortest path — decided by no one.
The station reads the colony while you interfere.
Everything above the field is instrumentation. The four counters sample the swarm in real time — how many ants are hunting, how many are hauling a seed home, how many round trips have closed since you loaded the page, and how much food-scent is currently laid across the ground.
Then reach in. Drop a crumb pile anywhere and a new trail gropes toward it. Wall off the direct line between nest and seed and the colony re-routes around the obstacle within a hundred trips — no ant ever seeing the whole map, no supervisor redrawing the plan.
- Foragers
- Ants currently hunting outward, following faint food-scent or, finding none, simply wandering.
- Laden
- Ants carrying a seed back to the nest, laying the bright food-scent that grows the trail.
- Trips
- Completed round trips, nest to seed and home again. Each one deepens the road a little.
- Trail
- Total food-scent on the field, normalised. It climbs as a route consolidates, dips when you cut it.
On the two scents
Real ants use several pheromones. This colony runs two: home and food. An outbound ant follows food-scent and lays home-scent; a laden ant follows home-scent and lays food-scent. Neither ant knows which is which — they just sniff and dribble.
Why walls work
A pebble wall holds no scent and blocks no ant's memory, because ants have none. It simply removes the ground under the fastest trail. The next-fastest route now closes its trips a hair sooner, and within roughly 80–120 trips its scent overtakes the dead one.
Crumbs run dry
The seed at the east edge is inexhaustible. A crumb pile you drop is not — it holds about 600 loads. Watch a bright thread reach a pile, thin as the pile empties, and evaporate to nothing once the last crumb is carried off.