Underland: A Deep Time Journey

by Robert Macfarlane

So these scenes from the underland unfold along the walls of this impossible chamber, down in the labyrinth beneath the riven ash. The same three tasks recur across cultures and epochs: to shelter what is precious, to yield what is valuable, and to dispose of what is harmful.

‘Deep time’ is the chronology of the underland. Deep time is the dizzying expanses of Earth history that stretch away from the present moment. Deep time is measured in units that humble the human instant: epochs and aeons, instead of minutes and years. Deep time is kept by stone, ice, stalactites, seabed sediments and the drift of tectonic plates. Deep time opens into the future as well as the past. The Earth will fall dark when the sun exhausts its fuel in around 5 billion years. We stand with our toes, as well as our heels, on a brink.

What these narratives all suggest is something seemingly paradoxical: that darkness might be a medium of vision, and that descent may be a movement towards revelation rather than deprivation. Our common verb ‘to understand’ itself bears an old sense of passing beneath something in order fully to comprehend it. ‘To discover’ is ‘to reveal by excavation’, ‘to descend and bring to the light’, ‘to fetch up from depth’. These are ancient associations. The earliest-known works of cave art in Europe – taking the form of painted ladders, dots and hand stencils on the walls of Spanish caves – have been dated to around 65,000 years ago, some 20,000 years before Homo sapiens are believed to have first arrived in Europe from Africa. Neanderthal artists left these images. Long before anatomically modern humans reached what is now Spain, writes one of the archaeologists responsible for the dating of this art, ‘People were making journeys into the darkness.’

I have for some time now been haunted by the Saami vision of the underland as a perfect inversion of the human realm, with the ground always the mirror-line, such that ‘the feet of the dead, who must walk upside down, touch those of the living, who stand upright’. The intimacy of that posture is moving to me – the dead and the living standing sole to sole.

We are often more tender to the dead than to the living, though it is the living who need our tenderness most.

Then he told me about new research he had recently read concerning the interrelations of trees: how, when one of their number was sickening or under stress, they could share nutrients by means of an underground system that conjoined their roots beneath the soil, thereby sometimes nursing the sick tree back to health. It was a measure of my friend’s generosity of spirit that – so close to death himself – he could speak unjealously of this phenomenon of healing.

The fungi and the trees had ‘forged their duality into a oneness, thereby making a forest’, wrote Simard in a bold summary of her findings. Instead of seeing trees as individual agents competing for resources, she proposed the forest as a ‘co-operative system’, in which trees ‘talk’ to one another, producing a collaborative intelligence she described as ‘forest wisdom’. Some older trees even ‘nurture’ smaller trees that they recognize as their ‘kin’, acting as ‘mothers’. Seen in the light of Simard’s research, the whole vision of a forest ecology shimmered and shifted – from a fierce free market to something more like a community with a socialist system of resource redistribution.

‘My childhood superheroes weren’t Marvel characters,’ Merlin once said to me, ‘they were lichens and fungi. Fungi and lichen annihilate our categories of gender. They reshape our ideas of community and cooperation. They screw up our hereditary model of evolutionary descent. They utterly liquidate our notions of time. Lichens can crumble rocks into dust with terrifying acids. Fungi can exude massively powerful enzymes outside their bodies that dissolve soil. They’re the biggest organisms in the world and among the oldest. They’re world-makers and world-breakers. What’s more superhero than that?’

Mutualism is a subset of symbiosis in which there exists between organisms a prolonged relationship that is interdependent and reciprocally beneficial.

The relationship between mycorrhizal fungi and the plants they connect is ancient – around 450 million years old – and largely one of mutualism. In the case of the tree–fungi mutualism, the fungi siphon off carbon that has been produced in the form of glucose by the trees during photosynthesis, by means of chlorophyll that the fungi do not possess. In turn, the trees obtain nutrients such as phosphorus and nitrogen that the fungi have acquired from the soil through which they grow, by means of enzymes that the trees lack.

Ecologists in the US seeking to understand how American trees will respond to the stress of climate change have begun to focus on the presence of soil fungi as a key indicator of future forest resilience. Recent studies suggest that well-developed fungal networks will enable forests to adapt faster at larger scales to the changing conditions of the Anthropocene.

Certainly, orthodox ‘Western’ understandings of nature feel inadequate to the kinds of world-making that fungi perform. As our historical narratives of progress have come to be questioned, so the notion of history itself has become remodelled. History no longer feels figurable as a forwards-flighting arrow or a self-intersecting spiral; better, perhaps, seen as a network branching and conjoining in many directions. Nature, too, seems increasingly better understood in fungal terms: not as a single gleaming snow-peak or tumbling river in which we might find redemption, nor as a diorama that we deplore or adore from a distance – but rather as an assemblage of entanglements of which we are messily part. We are coming to understand our bodies as habitats for hundreds of species of which Homo sapiens is only one, our guts as jungles of bacterial flora, our skins as blooming fantastically with fungi.

The work of the radical biologist Lynn Margulis and others has shown humans to be not solitary beings, but what Margulis memorably calls ‘holobionts’ – collaborative compound organisms, ecological units ‘consisting of trillions of bacteria, viruses and fungi that coordinate the task of living together and sharing a common life’, in the philosopher Glenn Albrecht’s phrase.

The real underland of language is not the roots of single words, but rather the soil of grammar and syntax, where habits of speech and therefore also habits of thought settle and interact over long periods of time. Grammar and syntax exert powerful influence on the proceedings of language and its users. They shape the ways we relate to each other and to the living world. Words are world-makers – and language is one of the great geological forces of the Anthropocene.