No other organisms in the world provoke the joy or disgust that mushrooms do, and yet, far beyond any of our personal feelings, mushrooms have a vital role to play in life on our planet. In recent years, there has been a growing awareness of the many sophisticated problem-solving behaviours that have evolved in brainless organisms outside the animal kingdom. The best known examples are slime moulds, such as Physarum polycephalum, which are expert problem solvers. When faced with a maze, slime moulds can compare different courses of action and determine the most efficient way out.
Japanese experts did an experiment which involved releasing slime moulds into petri dishes modelled on the Greater Tokyo area. Oat flakes marked major urban hubs and bright lights represented obstacles such as mountains (slime moulds don’t like light). After just one day, the mould found the fastest route through the oatmeal, and surprisingly, its network was almost identical to Tokyo’s existing rail system.
The fact that Physarum moulds can move around their environment and make decisions despite not having a brain or central nervous system means that they do have some sort of intelligence, even though in a form which is completely different from that of humans. Mushrooms form elaborate shapes, made up of a set of sculpted tufts of one type of cell, called hyphae. As they grow, the hyphae branch out and become entangled with each other, forming a dense network known as mycelium.
Hyphae also form more specialised structures, such as fruit bodies, one of the purposes being to spread reproductive spores. The mycelial networks are like a swarm of hyphal apex. Each apex operates individually, and there is no leader or central command centre. At the same time, all hyphal apices are connected to each other, in fact it is impossible to demolish a mycelial network one hypha at a time. However, if we reduce a mycelium to a single thin tube, it can actually regenerate its entire network all over again. This means that the mycelium is both a single entity and a multitude of individual parts at the same time.
For human beings, this concept is very important; it might seem easy to define the boundaries of our body, because as far as we can see, we end where the body ends, but that's not quite the case.
Our bodies contain entire communities of bacteria, microbes, genes, and cells obtained or inherited from different sources, without which we would become ill or even die. It is likely that the human body, just like mushrooms, is both an individual and collective living community. Perhaps we should re-assess the concept of individuality and self-reliance.