French zoologist and naturalist Georges Cuvier (1769–1832), one of the most eminent scientific figures of the early nineteenth century, is best known for laying the foundations of comparative anatomy and palaeontology. He spent his lifetime studying the anatomy of animals, and broke new ground by comparing living and fossil specimens - many he uncovered himself. However, Cuvier always opposed evolutionary theories and was during his day the foremost proponent of catastrophism, a doctrine contending that geological changes were caused by sudden cataclysms. He received universal acclaim when he published his monumental Le règne animal, which made significant advances over the Linnaean taxonomic system of classification and arranged animals into four large groups. The sixteen-volume English translation and expansion, The Animal Kingdom (1827–35), is also reissued in the Cambridge Library Collection. First published in 1817, Volume 2 of the original version covers reptiles and fish.