Tropical forests have played a central role in the conceptual development of biology from the time of the major biological expeditions that began at the close of the eighteenth century.
Alexander Von Humbolt initiated the study of plant ecology on his voyages through South America in the early nineteenth century. While climbing Mount Chimborazo in the Andes, Von Humbolt characterized the vegetation changes with climate as he ascended. These early observations on plant distributions provided the foundation of the field of biogeography. The most significant development in biological thinking inspired by tropical forests was the theory of evolution by natural selection. Charles Darwin and Alfred Russel Wallace independently derived this theory as a result of their scientific voyages in the tropics during the mid nineteenth century. Darwin’s inspiration was his exploration of various parts of South America as the naturalist aboard the Beagle beginning in 1831.
Wallace conducted expeditions in both South America (1848–1852) and the Malay Archipelago (1854–1862), where he characterized two sets of fauna distinct to the different parts of the archipelago, a division now known as Wallace’s Line. For both Darwin and Wallace, the high diversity of species in the tropics, and particularly patterns of diversification associated with island groups, allowed an appreciation of evolutionary relationships not apparent in the poorer faunas of the temperate zone. The high diversity of the tropics continues to be an important inspiration and testing ground for ideas in biology, particularly in the fields of ecology and evolutionary biology.