Seventeen years ago, Jared Leadbetter peered into an eyepiece and saw a microcosm in a milliliter. He’s still watching now, and still wondering.

A rich profusion of microbes swarms through a termite’s gut, staging an elaborate play of life on a stage smaller than a dewdrop. Scores of wormlike spirochetes thrash in wild hordes around a single, giant Trichonympha, itself smaller than a grain of sand. Nearby, several Streblomastix cells flap whiplike flagella to spin in incessant circles, seemingly oblivious of the deliberate, pulsating approach of a conelike Trichomitopis from the left.

The protozoa, large, single-celled eukaryotes easily studied with a light microscope, float through a sea of innumerable micron-sized blips. Those blips are some of the many bacteria sharing the residence.

In all, about 250 distinct species interact in a termite’s gut. This entire community rests inside the gut of every termite. It’s an entire economy run on wood. Leadbetter wants to know how it works.

Digesting wood presents a unique challenge. Wood is made of a tri-laminate composite: three gargantuan polymers horribly entangled in one another. The molecules comprising wood are so complicated that chemists’ standard techniques cannot tease apart the components of their native structure the way they can for more straightforward polymers, such as hemoglobin or DNA.

Decomposing a molecule like that demands extreme specialization. A few fungi can do it, and a few protists and bacteria. But termites are a rare exception to the rule that wood is too tough for animals to handle.

Devoid of the circus fair of microorganisms it drags along in its gut, a termite’s stomach is horribly weak. Termites can digest only one food source – the exceedingly simple molecule acetate. The hard work of taking particles of wood and turning them into the acetate the termite eats is left to the protozoa and bacteria inside the termite’s gut.

So how do they do that? What is the life story of a tree from the time it stops being a part of your house to the time it becomes a termite’s midnight snack?

When asked, Leadbetter leans back in his chair, folds his hands behind his head, and laughs. “We don’t know shit from Shinola,” he says.

Leadbetter does know that a termite’s gut is an ideal environment for exploring the way microbes interact. “This is a model community that we can study. It’s simple in that it has distinct boundaries, but complex in that there are many species. It’s a very attractive place to try to learn something substantive,” he says.

The power of studying a termite gut is that it can be isolated and manipulated, while controls are left sitting in a plastic box in the lab. Leadbetter points out that this isn’t something you could do with a larger environment, like the Sargasso Sea.

For example, Leadbetter might place some termites on a pure-starch diet, while feeding other termites cellulose, a more complicated molecule. In the guts of starch-fed termites, certain microbes will gradually disappear. When these starch-fed termites are once again given cellulose to eat, they’re no longer able to digest it. This allows the deduction that the absent microbes were important in digesting cellulose.

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