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Alexander von Humboldt, German author, naturalist and explorer, 1847. Humboldt's (1769-1859) interests included geophysics, geology and botany and he is sometimes called the founder of ecology. In 1800-1804, together with the French botanist Aime Bonpland (1773-1858), he explored the Orinoco and Amazon regions and collected 60,000 plant specimens. From a private collection.