Francis Gooding, 20 May 2021
Fungal mycelium is very good at finding the most economical route between points of interest. The mycologist Lynne Boddy once made a scale model of Britain out of soil, placing blocks of fungus-colonised wood at the points of the major cities; the blocks were sized proportionately to the places they represented. Mycelial networks quickly grew between the blocks: the web they created reproduced the pattern of the UK’s motorways (‘You could see the M5, M4, M1, M6’). Other researchers have set slime mould loose on tiny scale-models of Tokyo with food placed at the major hubs (in a single day they reproduced the form of the subway system) and on maps of Ikea (they found the exit, more efficiently than the scientists who set the task). Slime moulds are so good at this kind of puzzle that researchers are now using them to plan urban transport networks and fire-escape routes for large buildings.