Notes

New Ideas from Geology
In 1749, French naturalist Georges-Louis Buffon (1707–1788) became one of the first to openly suggest that closely related species arose from a common ancestor and were changing—a radical idea at the time. By moving the discussion into the public arena, he made possible a new consideration of evolution and its causes from a scientific point of view.
Meanwhile, in the 1700s and 1800s, much of the study of nature focused on geology. In 1785, physician James Hutton (1726–1797) proposed the theory of uniformitarianism, which suggested that the processes of erosion and sedimentation that act in modern times have also occurred in the past, producing profound changes in Earth over time. On the other side, Georges Cuvier (1769–1832) was convinced of catastrophism, the theory that a series of brief, violent, global upheavals such as enormous floods, volcanic eruptions, and earthquakes were responsible for most geological formations.

Figure 11.2 Rock Layers Reveal Earth’s History. Layers of sedimentary rock formed from…
Cuvier also used his knowledge of anatomy to identify fossils and to describe the similarities among organisms. He was the first to recognize the principle of superposition—the idea that lower layers of rock (and the fossils they contain) are older than those above them (figure 11.2). Although he had to accept that some species must have become extinct, he refused to believe that they were not originally formed through creation. He argued that catastrophes would destroy most of the organisms in an area, but then new life would arrive from surrounding areas.