Humans are transforming the Earth through our carbon emissions. Arctic sea ice is shrinking, seas are rising, and the past four years have been the hottest since record-keeping began. But long before the first cars or coal plants, we were reshaping the planet’s ecosystems through humbler but no less dramatic means: pastures and plows.
Environmental scientist Erle Ellis has studied the impact of humanity on the Earth for decades, with a recent focus on categorizing and mapping how humans use the land—not just now, but in the past. And his team’s results show some startling changes. Three centuries ago, humans were intensely using just around 5 percent of the planet, with nearly half the world’s land effectively wild. Today, more than half of Earth’s land is occupied by agriculture or human settlements.