When it comes to perceiving the extent of the fungal kingdom, our senses are wholly inadequate. Most fungi that humans tend to notice are the ephemeral sexual fruiting bodies we hunger for—for food, for medicine, for beauty, for blowing our minds. Homo sapiens’ sense of smell atrophied long ago; if we even want to find underground truffles, we need dogs and pigs. In the limited and delineated ways of human thinking—“animal, plant, or mineral?”—fungi defy categorization as we usually conceive of it. Long lumped in with plants, fungi were only recognized as their own kingdom in 1969.
They are neither plant nor animal, but a wild conglomeration of things, existing in ways that are so central to ecosystems that what we have learned about them forces the breakdown of traditional taxonomy. Large-scale DNA-sequencing datasets are expanding daily, but identifying a double helix doesn’t tell you how an organism exists in relationship with everything around it. And even with what we have learned, scientists from the Royal Botanic Gardens at Kew estimate that as many as 95 percent of the planet’s fungal species have not yet been identified.
For the species we do know about, the vast majority are mycorrhizal, living in close relationship with a photosynthetic partner, exchanging resources so both can survive and thrive. Plants give their carbon-laced sugars to the fungi, and the fungi exponentially increase the plant’s uptake of nutrients and water in exchange. This partnership allows plants to better tolerate stresses, from droughts to pests to pathogens, and helps trees like Douglas firs and redwoods reach their towering heights. Author Merlin Sheldrake describes mycelium, which makes up the mycorrhizal network, as the “ecological connective tissue, the living seam by which much of the world is stitched into relation.”
