Fossils and the Record of Previous Worlds
By the end of the 18th century, fossils had long been recognized as the remains of formerly living creatures. However, their full significance, as both archival evidence of past environments and as diagnostic tools for describing the relative age of the rocks in which they were found, was only just coming into view. Prior to the 18th century, savants considered fossils along with minerals as objects of “natural history”, related to taxonomy and classification. The examination of fossils was an indoor pursuit, carried out in museums and personal collections, with little or no context for the rocks in which the fossils were found, or even the region in which they were collected. Starting in the early 19th century, the fossil record began to serve as a crucial means for dividing and classifying different Eons, or slices of Earth’s history. In this sense, fossils are markers of the environments of past worlds and have a historical context.