by Eyal G. Frank, Qinyun Wang, Shaoda Wang, Xuebin Wang, Yang You
How do large disruptions to ecosystems affect human well-being? This paper tests the long-standing hypothesis that China’s 1958 Four Pests Campaign, which exterminated sparrows despite scientists’ warnings about their pest-control role, exacerbated the Great Famine—the largest in human history. Combining newly digitized data on historical agricultural productivity in China with habitat suitability modeling methods in ecology, we find that, after sparrow eradication, a one-standard-deviation increase in sparrow suitability led to 5.3% larger rice and 8.7% larger wheat declines. State food procurement exacerbated these losses, resulting in a 9.6% higher mortality in high-suitability counties—implying nearly two million excess deaths.