Not so long ago, the majority of the Earth was blanketed in forests and jungles, vast deserts, and sprawling savannas. But these days, the Earth’s wilderness is rapidly eroding. The Verge reports that, according to a recent study published in Current Biology, 10 percent of the Earth’s wilderness has disappeared in the last two decades alone.

Researchers from the Wildlife Conservation Society analyzed satellite and survey data since the 1990s in order to measure the loss of the Earth’s untamed places. They defined wilderness as “biologically and ecologically largely intact landscapes that are mostly free of human disturbance.” By their definition, wilderness landscapes cease to be wilderness not when humans settle there—the researchers note that many indigenous peoples help preserve rather than erode wilderness—but when humans disturbed ecosystems with land conversion, industrial activity, or large-scale infrastructure projects.

They found that, globally, 1.2 million square miles of wilderness have disappeared over the last 20 years, with the greatest loss occurring in South America (about a 30 percent loss) and Africa (14 percent loss). Today, only 23 percent of the Earth’s terrestrial area is wilderness. That’s bad news for a few reasons: The erosion of wilderness could have a negative impact on wildlife, indigenous communities, and climate change. Additionally, destroying even a small chunk of an ecosystem can have a negative impact on the rest, since wilderness areas are interconnected and interdependent.

Study co-author Oscar Venter told PRI that while he expected some wilderness erosion, he was shocked by the study’s results. "The amount of wilderness loss in just two decades is staggering," he explained. "We need to recognize that wilderness areas, which we've foolishly considered to be de facto protected due to their remoteness, is actually being dramatically lost around the world."

[h/t The Verge]

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