“Lines of the geography of plants,” by Alexander von Humboldt, 1817 CE.
“Lines of the geography of plants,” from De distributione plantarum (On the Distribution of Plants) by Alexander von Humboldt, 1817 CE.
Darwin’s Beagle journals are peppered with admiring references to the great Prussian naturalist and explorer Alexander von Humboldt (1769-1859). Among his many interests, von Humboldt aimed to explain the underlying causes for the uneven distribution of plants across the globe. This illustration depicts the different levels of vegetation on mountains in three distinct climate zones, demonstrating the effect of latitude and altitude on the ability of different plants to grow.
The American Philosophical Society Museum, “Dialogues with Darwin,” at http://www.pachs.net/dialogues-with-darwin. Book in the Public Domain.