When you make the sacrifice in marriage, you’re sacrificing not to each other but to unity in a relationship —Joseph Campbell

Preamble Lichens are the emergent and durable outcome of a complex set of reciprocal interactions between, at a minimum, two unrelated organisms: algae/cyanobacteria that produce their own foodstuffs and fungi that sustainably consume it.

Said another way, lichens are tantamount to a living world you can hold in your hand. Not only do they embody many of the principles that initiated and sustain life on Earth, they also, on this account, provide an unexcelled heuristic for contemplating the Climate Crisis as an outcome of rationalist modes of thought rooted in the Enlightenment.

Said another way still, the shortest path from Enlightenment to Enlivenment is through Enlichenment.

First Approximation

o engage in meaningful conversation with the Living World is no easy thing. This is true for people of any culture of any time past or present – whence the shaman – but it’s especially true for western peoples today. How could it be otherwise? Girded as we westerners are with a stubbornly rationalist turn of mind, and increasingly caught up as we are in the entangling web of the human technosphere, few of us are inclined to give the matter much thought. And of those who do give it some thought, most seem to feel that conversation with the Living World is no longer possible, if indeed it ever was.

Such people might to do well to spend time with lichens. Lichens: the great intermediaries, occupying a conceptual space where relationship becomes material, where organism meets ecosystem, where the parts meet the whole, where domesticity meets the wild, and where doubters, if they’re honest, meet their match. They’re the Living World you can hold in the palm of your hand.

The defining characteristic lichens, the one characteristic that sets lichens apart from just about anything else you care to name is their status as dual organisms, that is, part fungus and part alga. Seen on the outside, lichens are an emergent outcome of fungi that have discovered algaculture. Viewed on the inside, they’re fungi that, instead of invading or scavenging for a living, like most other fungi, sustain themselves on sugars tapped from tiny photosynthetic algal cells cultivated within living fungal greenhouses of their own making.

What’s salient about the lichen partnership is that the lichen fungus doesn’t parasitize or otherwise harm its algal partner. Instead, it engages in algaculture – sheltering, watering, feeding, repositioning its algal partner as necessary. No greenhouse gardener tends her tomatoes with more attention than a lichen fungus lavishes upon its multitudinous algal cells. Only once an aging algal partner is past its prime, only then does the fungal partner finally harvest it.

The body of a lichen is called a thallus. The greater part of most lichen thalli consists of fungal hyphae: tiny, hollow, interweaving “threads” that grow by absorbing nutrients from their immediate environment, most conspicuously photosynthates from the algal partner, as I say, but also from whatever comes their way when the rain falls or the wind blows.

As dual organisms, lichens occupy a conceptual space at the core of current thinking about the nature of macroscopic life. You could say that lichens exist at a kind of doorway. Look out this doorway in one direction, and what you see is ecosystem: two or more unrelated organisms living in symbiosis. Yet look out that same doorway in the other direction, and what you see now is organism: a living system fully integrated and endowed with emergent properties unheard of in either partner on its own.

Still, the quintessential thing about the lichen thallus is its status as pure relationship: the emergent outcome of two similarly sized partners in continuous conversation with one another. How indeed could it be otherwise? While it’s true that the lichen fungus tends assiduously to the lichen alga, it’s no less true that such would be impossible without the algal partner signalling its various physiological needs. Lichens are not merely fungi that have discovered algaculture, they’re also algae that have discovered domesticity.

It has been suggested (full disclosure: by me actually) that lichens are, in a degree, the sound of one hand clapping – an observation that gestures to their usefulness as object lessons in a great many thought experiments concerning the workings of the Living World, not least in coming to terms with some of the hefty paradoxes at its heart.

Enlichenment, as I say.

Next up: Lichen Rule