Darwin, Lyell, and the Geological Significance of Coral Reefs

Abstract

In the half century following Cook's entry into the Pacific in 1769, few tropical phenomena excited more attention than coral islands and the corals which evidently built them. In the eighteenth century corals occupied a critical position in the Great Chain of Being. Sometimes interpreted as animals, sometimes as plants, they built large topographic structures of limestone, and thus spanned the gap between the organic and inorganic worlds. ‘The strata which they form are at once living and fossil; we can see them in the act of production, and the mountains grow up to the day before us, new parts of our own earth.’ Towards the end of the century, after Peyssonnel had conclusively shown that corals were animals—variously designated as worms, insects, or molluscous worms—this bridging significance was transferred to the coral islands, new areas of land emerging from the ocean and newly colonized by plants and animals, as an analogue of the primeval earth. This creative process served for some to counterbalance the Huttonian vision of universal degradation: ‘Whatever destroying tendencies … exist on the earth, these renovating powers compensate for them’.