Jo: What is your relationship with microbes?

David: There isn’t a human being on Earth that isn’t in a deeply enmeshed and utterly intractable relationship with microbes. We are absolutely dependent on them. We are evolved from them. They are the ground floor for life.

If you look at the diversity of bacteria or of yeast - or protozoa, or amoebas - it dwarfs the diversity of the animal and plant world. Anything that we can see with our eyes is a fraction of the complexity of microbial evolution. They live on and in me. I’m dependent on them for normal digestion. My gastrointestinal tract, the health of my skin, all of it is dependent on microbes that use me as an environment. Organisms are more than just environments to each other. Organisms are entire worlds.

Everything from the pets in your house to a tree in a forest, they’re all dependent on microbes to function. And there’s this endless interchange of metabolic and bioinformational communication that mediates our world.

To engage with a microbe beyond, say, catching a cold or getting an ear infection, to actually understand what they need and how they work and their rhythms and their cycles - I see fermentation as an extraordinarily powerful tool to be able to foster relationships with microbes in which you understand their needs and their wants.

I don’t mean to anthropomorphise these creatures that are really, in so many ways, at once the most complex things imaginable but at the same time the simplest forms of life. But ultimately, what you do when you interface with microbes through fermentation, by working with them, by coaxing out the products of their metabolisms, you’re really interfacing with the rhythms of life itself.

Fermentation has definitely changed how I live in and view the world. The funny thing is going through it with them, learning about microbes so intimately, is a kind of ratchet. There’s no going back. Once you’ve seen the world from their perspective, you can’t unsee it, and everything forever onwards is filtered through a microbial view of life.