“To spread healthy ideas among even the lowest classes of people, to remove men from the influence of prejudice and passion, to make reason the arbiter and supreme guide of public opinion; that is the essential goal of the sciences; that is how science will contribute to the advancement of civilization, and that is what deserves protection of governments who want to insure the stability of their power.” – Georges Cuvier, as quoted in Clifford D. Conner, A People’s History of Science (2005).

Georges Cuvier – Wikimedia Commons / Public Domain

Georges Cuvier (1769 – 1832) was a French naturalist and statesman, who is best known for founding the disciplines of comparative anatomy, and vertebrate paleontology, as well as the establishment of the concept of extinction as matter of fact—a radical idea at the time. He was born in the french-speaking town of Montbéliard, under the jurisdiction of the Duke of Württemberg. A brilliant figure,  he finished Buffon’s 36-volume Histoire Naturelle (Natural History) at the age of twelve and won first place for competence in German, at the German-speaking college Herzogliche Karls-Universität in Stuttgart, only nine months after being introduced to the language. Some time after graduating, Cuvier was invited by Étienne Geoffroy Saint-Hilaire to work at the Musée National d’Histoire Naturelle (National Museum of Natural History) in Paris, where he later became a professor of animal anatomy.

Cuvier is a fascinating person, not only for his accomplishments in science, but for his accomplishments in government. He lived through the most dangerous period in French history, having served as an important government official under the revolutionary government, Napoleon, and the monarchy. Napoleon appointed Cuvier Inspector-General of public education, and soon after he set about reforming the French educational system, organizing provincial schools across the country. Despite his non-noble birth, Napoleon awarded him the title of Chevalier in 1811.

During this time, dominant thought followed that an animal’s anatomy was determined by its environment and how it behaved. However, in his  Leçons d’anatomie comparée (Lessons on Comparative Anatomy), Cuvier offered the opposite opinion. He believed that an animal’s anatomy was, instead, determined by how it interacted with its environment. His “correlation of parts” theory proposed that the structure and function of an animal’s organs were related to all the other organs in its body, and that the structure and function of all organs were determined by the animal’s interaction with the environment. Using his theory, Cuvier showed that animals possess an immensely diverse number of anatomical traits, and realized that they could not be arranged into a linear system of classification—which they were at the time. Because of this, he created a new system of classification: vertebrates, mollusks, articulates and radiates.

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Figure of the jaw of an Indian elephant and the fossil Jaw of a mammoth from Cuvier’s 1798–99 paper on living and fossil elephants – Wikimedia Commons / Public Domain

Cuvier’s correlation of parts theory would eventually lead to the development of his thought on extinction. At the time, the idea that extinction occurred was not widely believed because it contradicted dominant Christian thought. If all life was created according to God’s divine plan, it would be irrational for him to allow some of it to go extinct. However, strange fossils belonging to dinosaurs and other long lost animals were being discovered across Europe. Mammoth fossils excavated in Italy were believed to have been the remains of the war elephants used in Hannibal’s invasion of Rome. Cuvier applied his theory of the correlation of parts to Mammoth bones in France, and found that they were distinctly different from bones found in Africa and India. This discovery lead him to believe that these bones belonged to a separate species which had gone extinct. In 1813 he published his work Essay on the Theory of the Earth, where he described his theory of Catastrophism—the idea that major catastrophes, or what he called “revolutions”, such as earthquakes and floods, lead to the extinction of certain species. Cuvier was soon considered the world’s leading expert on vertebrate paleontology and animal anatomy. It is said that he could reconstruct entire skeletons from a single bone.

Cuvier’s theory of Catastrophism led him to denounce Jean Babtiste Lamarck’s early theory of evolution. While examining fossils, Cuvier never found evidence of fossils changing from one form to another. He argued that each species was structured and functioned in such a way that it would not survive the significant changes required for evolution. In response to Lamarck he wrote:

“If the species have changed by degrees, we ought to find traces of these gradual modifications. Thus, between the palaeotheria and our present species, we should be able to discover some intermediate forms; and yet no such discovery has ever been made.” – Georges Cuvier, from his Essay on the Theory of Earth: 103 (1827).

His findings, however, would eventually lay the foundation for Charles Darwin’s theory of evolution. During his work, Cuvier discovered that the further they excavated, the more distinct the fossils they found—essentially that the deeper they dug, the farther back in time they went. Further, now that extinction was established as matter as fact, any future theory of evolution would need to explain it.