A top-down cutaway of a honey bee hive where four real bee pheromones — queen mandibular, brood, alarm and Nasonov — spread through a genuine 2D diffusion-advection-decay field (∂C/∂t = D∇²C − kC + S) and visibly steer the movement of hundreds of worker bees.
Each signal diffuses and decays at a different rate: queen and brood pheromone attract nearby workers up the concentration gradient, alarm pheromone drives workers rapidly down-gradient away from the threat, and Nasonov scent — carried outward by a fanning-driven drift term — recruits foragers waiting outside back through the hive entrance.
Pick a signal, then raise the emission strength and airflow/fanning rate to watch the field's peak and mean concentration climb in the live readout, and adjust the worker population to see the effect at colony scale.