GEORGES CUVIER: French anatomist and paleontologist. 1769-1832. Worked at the French National Museum in Paris. Studied wooly mammoths and mastodons, and showed conclusively that these elephant-like animals are not members of the modern elephant species, and therefore represent earlier elephant relatives that no longer exist. He thus demonstrated that species can go extinct (an issue much discussed at the time), and that extinction is a real biological phenomenon. In doing this, he thus completed the conceptual framework needed to understand dinosaurs as extinct fossil animals.