One scientist argued the entire planet behaves like a single living system

In the early 1970s, James Lovelock proposed that Earth's atmosphere, oceans and living organisms interact as a self-regulating system that keeps conditions stable enough for life, an idea he named the Gaia hypothesis after the Greek Earth goddess. Initially dismissed as unscientific, it has since shaped how researchers study feedback loops between life and climate.

— James Lovelock, Gaia: A New Look at Life on Earth — 1979
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