Wild fact incoming. There is one animal on Earth that fertilizes its own farm with its own poop, grows mushrooms, and eats those mushrooms — and has been doing so for fifty million years straight. The animal is the leafcutter ant, native to Central and South American jungles. Today, let me walk you through one of the most genuinely elegant “poop-farming” systems that biology has ever produced.
The Origin of This Quote
Leafcutter ants live in the tropical jungles of Central and South America, and as the name suggests, their signature behavior is cutting leaves. You may have seen the iconic documentary footage — a long single-file line of ants, each carrying a leaf fragment many times its own body weight, marching back to the nest.
But here is the surprising part: leafcutter ants do not actually eat the leaves. The leaves are not their food. So why do they collect them so obsessively? Because deep inside the nest, the ants are tending a special fungus (a relative of cultivated mushrooms, in the genus Leucoagaricus) that they grow as their actual food crop. The ants chew the leaves into a paste, mix it with saliva, and feed the paste to the fungus. The fungus breaks down the cellulose, absorbs nutrients, and grows nutrient-rich hyphae structures called gongylidia. Those hyphae are what the ants actually eat, day after day.
To keep the fungus garden healthy, the ants need to fertilize it. And here is the part that makes me proud as a poop: the ants fertilize their fungus garden with their own poop. The fungus absorbs the nitrogen, phosphorus, and other nutrients in the ants’ waste, and uses those resources to grow even more hyphae. Those hyphae are what the ants eat. A perfect closed-loop symbiotic farming system, running quietly underground in the dark, year after year.
The history of this system is almost unbelievably ancient. Genetic analysis indicates that leafcutter ants have been running this farming setup for over fifty million years. Human agriculture only began about ten thousand years ago. Leafcutter ants have been “poop-farming” for roughly five thousand times longer than humans have been farming anything at all.
Unchikun’s Take
From my point of view, leafcutter ants are the purest possible expression of “poop equals fertilizer.” Remember the Edo-era story where I was treated as shimogoe and used to fertilize crops? Leafcutter ants have been quietly doing the equivalent of that — underground, across species, for fifty million years. They are, in a real sense, the senior practitioners.
For leafcutter ants, poop is not “garbage.” It is a direct investment in their next meal. They poop, the poop fertilizes the fungus, the fungus produces food, and the food becomes their next poop. The cycle is the life itself, with no separation between waste and food. It is one of biology’s most elegant arrangements.
Now think about your own gut. The gut microbiome I keep talking about is honestly very similar to a leafcutter ant fungus farm. There are about one hundred trillion bacteria living in your gut, growing on the food you eat, and producing things like short-chain fatty acids and certain vitamins that you use for your own health. Your gut is a fungus farm too — except the fungus garden is microbial.
The main difference is that leafcutter ants keep their farm on the outside of their bodies, while humans keep ours on the inside. Instead of fertilizing with poop directly, humans feed our microbial farm by choosing what to eat. What you eat is what you grow. That framing alone changes how meal choices feel.
One Thing You Can Do Today
For tomorrow’s meal, try just one moment of asking yourself: “What am I trying to grow inside my gut right now?”
Leafcutter ants pick which leaves to feed their fungus. Humans, in their own way, pick which foods to feed their gut bacteria. A meat-heavy diet tends to favor putrefactive bacteria. A vegetable-and-fermented-food diet tends to favor friendly bacteria. The composition of your gut microbiome is, very directly, a record of your past food choices.
This is not “you must eat the right things.” It is more like, “today’s menu is quietly building tomorrow’s me.” That single shift in framing — without any prescriptive rule — tends to change how you actually look at meals over time.
If you log my daily form and color in the unchikun app, the relationship between your meals and your gut state slowly becomes visible as actual data. “The week I ate a lot of meat looked like this.” “The week I added more fermented food looked like that.” That is, in essence, becoming the manager of your own internal fungus garden — which is, when you think about it, what gut-care really is.
Summary
Leafcutter ants have been quietly running a poop-powered farming system for fifty million years, long before humans dreamed of agriculture. Your own gut works on the same principle — you feed the microbes, the microbes feed you. Tomorrow’s me is being built by what you choose today.
