The American prairie once had three things in abundance: bison, tallgrass, and microbes.
According to ecosystem expert Wes Olson, these three entities – from completely different kingdoms, living on seemingly incompatible scales – formed an unlikely alliance that holds the whole place together. It’s glued by an equally esoteric material: bison snot.
It works like this: Like most places on Earth, the American prairie is absolutely suffused with micro- organisms. These bacteria, protozoa, and fungi cling to plants, hang suspended in drops of water, and float in the air.
As a bison sniffs and chews, some of these end up in her mouth, and others inside her elegant, comma-shaped nostrils, where they become trapped in snot. Every few bites, the bison digs her tongue in there to clear things out, swallowing more microscopic critters in the process.
Chewed grass, snot and microbes are then swept down into the rumen, the first of the bison’s four stomachs, where the microbes get to work breaking down the tough plant cellulose into nutrients the animal can use.
The exact microbe makeup varies depending on the season and the type of grass; the prairie’s microbial succession pattern allows the bison to move between foraging grounds without losing the ability to digest.
When a mouthful of grass has finished its journey through a bison, it emerges in another familiar form. A bison poops enough every day to fill a 3-gallon (11 L) bucket. This poop is generally known as dung, chips, or patties – no one seems to call it waste, maybe because it’s anything but.
Insects move into the bison chips to eat the microbes still hanging out there; then bats, birds and box turtles come to eat those bugs. People burn dried chips as fuel for warmth and cooking. And dung beetles chop some up and bury them, making them available to soil microbes, which transform the nutrients within into a form that can be used by plants. In this way, the prairie grass, after a few microbe-smoothed stops inside a ruminant, becomes itself again.
How to see bison
Best not to get snot-spottingly close to a bison – but with binoculars, you can watch them get their tongues way up in there.
This article is excerpted from Atlas Obscura: Wild Life: An Explorer’s Guide to the World’s Living Wonders by Joshua Foer & Cara Giaimo. Workman Publishing, 2024.
Main image: Bison on the prairie below the Grand Teton Range/Getty
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