by Adele A. Wilby
Recently I stepped into the underworld of fungi in Merlin Sheldrake’s Entangled Life: How Fungi Make our Worlds, Change our Minds and Shape our Futures. His book took me to an ancient world, tirelessly and inconspicuously working away and doing its vital job of literally interlacing the planet and holding it together to make life sustainable. The entry into this curious world was through the rather unassuming life form that most of us are more accustomed to eating than we are to learning about its existence: the mushroom.
Mushrooms are, for most of us, just another source of food, or indeed choose the wrong kind to consume and the adverse effects are likely to be more dangerous than delicious. They are though, fruiting bodies of fungi whose appearance on the surface is aimed at the reproductive role of dispersing millions of spores into the atmosphere to secure their existence.
Colourful mushrooms of all sizes and shapes poking their heads up from the leafy undergrowth of a woodland or forming colonies of various architectural designs on dead trees, have never failed to draw my attention during my wanderings through wooded areas. Fascinated by these humble looking elegant protuberances that decorate the forests, on some occasions I have taken the time to count the varieties I have seen and found several different types on any one day. But as I learned from Sheldrake, my enthusiasm for the diversity of the mushrooms I observed was quite trivial in comparison with the numbers of fungi on the planet: there are, literally, millions of species throughout the world.
According to Sheldrake, fungi amount to six to ten times the number of plant species and they are found everywhere on the planet. ‘Fungi,’ writes Sheldrake, ‘are metabolic wizards and can explore, scavenge, and salvage ingeniously, their abilities rivalled only by bacteria’. They are ‘regenerators, recyclers and networkers that stitch the world together’. Indeed, the ‘abilities’ of fungi seem limitless: its chemical behaviour breaks down lignin – wood’s toughest components – crude oil, plastics and even the explosive TNT. The site of the blasted nuclear reactor at Chernobyl is now home to a population of fungi. But fungi have been friends, not only to the planet for millions of years, but to human beings also. Without fungi, penicillin would not be available to us, nor would successful organ transplants have taken place without the immuno-suppressant drug cyclosporine and the number of heart attacks and strokes would probably be much higher without statins, to name just a few of life sustaining medications that have their origin in fungi.
The surface face of fungi is a minor aspect of its existence; what goes on underground, under our feet, is where all the action in the life of the fungi takes place, and that is the central theme in Sheldrake’s book that is most challenging and interesting for readers, and here I am referring to the mycelium that forms from fungi.
Sheldrake acknowledges that his research on fungi has compelled him to think the world differently. ‘Mycelium is’, he says, ‘a way of life that challenges our imagination’, and, as his book reveals, he is correct on that point. This is attributable to the way the fungi form into mycelium, an ‘ecological connective tissue, the living seam by which much of world is stitched in relation’. To get to this ‘connective’ stage, Sheldrake tells us, fungi must first form into ‘hyphae…fine tubular structures that branch, fuse, and tangle into the anarchic filigree mycelium’. But it is at this point that readers are required to step out of the anthropocentric association of intelligent life forms as having a brain and stretch our imagination when thinking about other life forms on the planet if we are to comprehend, and indeed appreciate, the ‘intelligent’ life form that is mycelium. Sheldrake says, ‘a mycelium network has no head and no brain. Fungi… are decentralised organisms…Mycelium coordination takes place both everywhere at once and nowhere in particular. A fragment of mycelium can regenerate an entire network’ and is ‘potentially immortal’. As he says, ‘mycelium is a way of life that challenges our animal imaginations’, it is a ‘body without a body brain’. Without a brain and without a defined body shape, how then does mycelium do the work it does to sustain life on this planet, and how can it be understood?
Sheldrake proceeds, in eloquent prose, to offer the reader a remarkable and accessible exposition of just how the networks of mycelium grow, form relationships, reproduce and indeed even make ‘decisions’. Inevitably any mention of decision-making by an organism without a brain immediately raises questions, and this is when we are called upon to suspend our anthropocentric thinking and imagine life forms beyond our brain-centred understanding of what is ‘intelligence’, a difficult task for most of us.
Inevitably, as Sheldrake acknowledges, there is considerable unresolved controversy within disciplines about what constitutes ‘intelligence’, but for Sheldrake, mycelium demonstrates behaviour that can be considered intelligent. Take one example, the case of ‘zombie fungi’, ophiocordyceps unilateralis, whose life revolves around carpenter ants. The ‘zombie fungi’ metaphor appropriately describes how fungi penetrate and modify its host’s behaviour before consuming it. Once the ants are infected, the fungi manipulate the ants to abandon their natural fear of heights, leave their nests, climb the nearest plant and sink their jaws into the plant. Mycelium then grows from the feet of the ant, effectively ‘sticking’ it to the plant’s surface. The fungi then digest the ant’s body from within, sprout a stalk, dispense its spores to the ants passing below, and the whole procedure is repeated, providing food that is consumed by the mycelium to feed the fungi. How the ‘zombie fungi’ control the insects, is the real puzzle for researchers.
Apart from highlighting both the ‘brilliance’ of fungi in its ability to manipulate the ants, the lack of explanation to account for the behaviour of the fungi highlights some of the mysteries about fungi and its mycelial network. Arguably, this network is more comprehensible in its relationships to plants, between whom the two have established a complimentary and life-sustaining relationship, and Sheldrake explores this in the chapter ‘Before Roots’. Describing this relationship, Sheldrake comments, ‘more than ninety percent of all plant species depend on mycorrhizal fungi… Out of this intimate partnership…plants and mycorrhizal fungi enact a collective flourishing that underpins our past, present, and future’. In other words, plants and mycorrhizal fungi live ‘entangled lives’, relentlessly transporting and exchanging life sustaining needs from one to the other.
Inevitably a book that deals with nature would be incomplete without a comment on the impact of human beings on the natural phenomenon being discussed, and so it is with Sheldrake. Predictably, given the human propensity to want to ‘control’ nature for it to work for humans, there are areas of concern. In this case it is industrial agriculture and the use of pesticides that pose a threat to this incredible life form. The destruction of the mycelium, Sheldrake suggests, would leave the soil without the connecting factor that holds the soil together and thereby risks the washing away of topsoil and the implications of that for agricultural production. But on a different note, Sheldrake discusses how the mycelium is a potential source to be grown and harvested for alternative uses by human beings that are more environmentally friendly.
Sheldrake’s book is packed with interesting content on a subject about which he writes so passionately. It is a book accessible to novices on the subject, but it is also sufficiently on a level to be of interest to a wide audience with various levels of understanding of the topic. The accessibility of the book should not belie the seriousness of the subject and the intellectual challenge that fungi raise in our understanding of different life forms with whom we share this planet. Sheldrake reveals to us just how fungi are indeed ‘one of life’s kingdoms’.