What did George Cuvier primarily study that led to the establishment of paleontology?

George Cuvier's work in the late 18th and early 19th centuries was pivotal in establishing the field of paleontology, primarily through his extensive study of extinction. He was among the first to suggest that species could become extinct, and he supported this idea with fossil evidence. Cuvier analyzed the remains of prehistoric animals and concluded that these creatures were distinct from modern species, leading to the realization that life on Earth had changed dramatically over time. By demonstrating that certain species no longer existed and correlating this with fossil findings, he laid the groundwork for understanding the history of life and the concept of extinction itself. His contributions helped establish a scientific framework for the study of fossils, making extinction a central theme in paleontological research.