the power of Systems Thinking

In the early 20th century, Yellowstone National Park’s managers envisioned transforming the park into a paradise for both visitors and hunters.

To protect livestock and game animals, wolves, the main predator, were systematically eradicated from the park.

By the 1920s, they were gone, and the elk population exploded without their natural predator.

For decades, this seemed like a win. More elk meant more wildlife to admire.

But then the cracks began to show....

Rangers noticed the park’s willow trees and aspen groves thinning along the riverbanks.

Beavers who relied on those trees to build their dams began struggling to find wood. Without enough dams, the rivers shifted—sometimes flooding, sometimes eroding—disrupting the calm pools where trout spawned. The landscape was changing and not for the better.

By the mid-20th century, scientists recognized the dominoes falling, but their attempts to address the problem failed.

Short-term solutions, such as planting trees or shoring up riverbanks, were ineffective because they didn’t consider the ecosystem of Yellowstone as a whole.

Then, in 1995, park managers took a bold step: they reintroduced the wolves.

Within a few years, the system began to heal itself.

Wolves thinned the elk herds and that changed the elks’ behavior, keeping them on the move and away from vulnerable riverbanks. Willows and aspen populations grew, providing wood for the beavers. Dams returned, stabilizing rivers and restoring fish habitats.

When given what was needed, the complex adaptive system, as a whole, began finding balance once again.

This story mirrors a flaw in modern medicine. Too often, we focus on symptoms—weight gain here, a lack of energy there —without tracing the upstream causes or historical choices that have shaped the system.