Why fungi knock the spots off humans
NATURE
THE splendidly named Merlin Sheldrake is the son of the maverick biologist Rupert Sheldrake, who famously came up with the idea of ‘morphic resonance’. This suggests that all living things somehow connect, have ‘memories’, and communicate with each other in ways we don’t understand.
Sheldrake the Younger continues a proud family tradition of non-conformity: he is a genial obsessive in the mysterious world of fungi. ‘More than 90 per cent of their species remain undocumented,’ he notes, and there may be as many as 3.8 million of them.
Right now, he says, fungi are ‘eating rock, making soil, digesting pollutants, nourishing and killing plants, surviving in space, inducing visions, making medicines and manipulating animal behaviour’.
They’re also the largest and oldest living things on earth. One fungus in Oregon in the U.S. weighs thousands of tonnes, covers 10 sq km, and might be 8,000 years old, starting out when there were still woolly mammoths around. In furtherance of his enquiries, the book’s mycophile author once ‘lay naked in a mound of decomposing wood chips’. He’s even, under medical supervision, taken LSD which is reputed to induce feelings of connectedness.
It turns out that the relatively recent discovery of the ‘Wood Wide Web’ denotes just this: a vast and astonishingly complex fungal network that lives underground, linking plants, fungi and bacteria in both a nutrient and information highway.
Like our own morally mixed World Wide Web, the Wood Wide Web isn’t only about mutual exchange and kindly co-operation. Plants also use it to kill each other. In one experiment, walnut trees emitted a toxic compound in their fallen leaves which then travelled via underground networks to poison some nearby tomato plants, thus reducing their power to compete.
But it’s becoming harder and harder for biologists to think of any single organism as being really just that: you and I aren’t simply human individuals, we’re also walking, talking colonies of trillions of bacteria and fungi.
Only 43 per cent of our cells are human — we’re mostly a microbial megacity, usefully protected and fed by a temporary sheath called a human being. When this sheath dies off, the inhabitants of the megacity swarm out and devour it, and then move on elsewhere.
On a more positive note, maybe it’ll be fungi which will finally help us clear up the dreadful plastic pollution we have created. South Korean scientists have discovered a beetle whose larvae can digest polystyrene, thanks to their gut flora. And others have found a strain of white rot fungi that can digest cigarette butts. Somewhere out there may be some tiny threadlike organism which can happily munch through mountains of supermarket shopping bags and discarded plastic toys (made in China, binned in Britain), and turn them into the richest, finest compost. A company in New York has also created something called ‘mycelium leather’, a material made by fungal activity, which Stella McCartney is considering using for her handbags. entangled Life is a captivating trip into the weird and wonderful mycorrhizal world around us — and inside us. It’s full of startling revelations, detailed science and just enough eccentric humour to make it digestible. A joy.