Watershed
Two colonies, blind to each other, share one field. Each is drawn to its own kind and turns away from the other. Two networks grow, meet, and settle a frontier between them. Choose a side and feed it, and the divide moves.
About this piece
Yesterday’s piece was one slime-mold network finding its own paths. This one is two of them, sharing a single field and competing for it. Every one of the 147,456 agents belongs to one of two colonies. The rule each follows is the same as before — smell the field ahead, steer toward the strongest trail, deposit where you land — with one change: an agent is drawn to its own colony’s deposits and repelled by the other’s. Attraction in, repulsion across.
That single change is enough to make a border. Each colony thickens its own ground and avoids its rival’s, so where the two networks meet, neither will build. A dark seam opens between them and holds — a watershed, the line where the pull of one territory gives way to the pull of the other. Nothing decides where it falls except the balance of the two pressures. No agent can see the border; the border is only the place their two blind appetites cancel.
When you choose a side and drop food, you are not commanding anyone. You are sweetening one colony’s ground. Its veins grow toward the food, its deposits deepen, and the frontier drifts into the rival’s land — until you feed the other side, or clear the field and let the two find their own line again. A border is not a thing. It is a truce between two things that cannot see each other, written in a field they both can read.