The Rational Optimist: How Prosperity Evolves

by Matt Ridley

Take the place where I am sitting. Supposedly, its climax vegetation is oak forest, but the oaks only arrived a few thousand years ago, replacing the pines, the birch and before that the tundra. Just 18,000 years ago, where I sit was under a mile of ice, and 120,000 years ago it was a steaming swamp complete with hippos. Which of these is its ‘natural’ state? Besides, even if the climate settled down to an unvarying stability (something it has never done), oak saplings cannot thrive under oaks (oak-eating pests rain down on them), so after a few thousand years of oak domination an oak forest gives way to something else. Lake Victoria was bone-dry 15,000 years ago. The Great Barrier Reef was partly a range of coastal hills 20,000 years ago. The Amazon rainforest is in a state of constant perturbation: from tree falls to fires and floods, its diversity requires it to be constantly changing. There is no equilibrium in nature; there is only constant dynamism. As Heraclitus put it, ‘Nothing endures but change.’