The similarities of their coastal plants, Humboldt wrote, showed an ‘ancient’ connection between Africa and South America as well as illustrating how islands that were previously linked were now separated – an incredible conclusion more than a century before scientists had even begun to discuss continental movements and the theory of shifting tectonic plates. Humboldt ‘read’ plants as others did books – and to him they revealed a global force behind nature, the movements of civilizations as well as of landmass. No one had ever approached botany in this
