We would see sprawling, interlaced webs strung through the soil, through sulphurous sediments hundreds of metres below the surface of the ocean, along coral reefs, through plant and animal bodies both alive and dead, in rubbish dumps, carpets, floorboards, old books in libraries, specks of house dust and in canvases of old master paintings hanging in museums. According to some estimates, if one teased apart the mycelium found in a gram of soil – about a teaspoon – and laid it end to end, it could stretch anywhere from a hundred metres to ten kilometres.
