Jim Lovelock was a late bloomer. His first book, Gaia: a New Look at Life on Earth, was published in 1979 when he was already 60 years old. By the time he died last Thursday, on his 103rd birthday, he had written ten more books on Gaia, the hypothesis that has evolved into the key academic discipline of Earth System Science.
That gives him a strong claim to be Charles Darwin's legitimate heir. Just as Darwin's 19th-century theory of evolution shaped our understanding of how life became so diverse, our understanding of the present is shaped by Lovelock's idea that the millions of living species function as a self-regulating mechanism that keeps the planet cool enough for abundant life.
The puzzle that started Lovelock down that road was the fact that the Sun's radiation has increased by 30% since life appeared on Earth 3.7 billion years ago, while the planet's average temperature, despite occasional huge surges up or down, has consistently returned to the narrow range most suitable for life.
