Mycorrhizal Biological Market: Partner Choice (2D)

Underground, a single fungal network can link the root systems of many plants at once — a common mycorrhizal network. This 2D edition models the same trade as the 3D version — each round every root pays a carbon ration into the network and the fungus allocates its shared phosphorus pool back in proportion to what each root paid — but renders it as a live Sankey-style flow diagram plus a carbon-vs-phosphorus phase plot instead of a spatial garden scene. Drag any root's carbon slider down to simulate a shaded "free-rider" plant, tune how strongly the fungus discriminates between generous and stingy partners, and switch reciprocal rewards off entirely to see the phase plot collapse to a flat line — exactly what partner choice, first demonstrated with isotope tracing by Kiers et al. (2011), prevents in real mycorrhizal fungi.