Georges Cuvier was a French naturalist and paleontologist born in 1769. He is best known for establishing extinction as a fact, demonstrating that many species that once existed no longer do. Cuvier's work laid the foundation for the field of paleontology, and he developed the concept of catastrophism, which suggests that Earth's geological features are shaped by sudden, short-lived events. Cuvier's studies of fossils helped classify animals into groups based on their anatomical structures. He contributed significantly to the understanding of comparative anatomy, influencing later scientists like Charles Darwin. His legacy continues to impact biology and geology today.