World of Earth Science | Cuvier, Georges (1769-1832)

French naturalist

Georges Léopold Chrétien Frédéric Dagobert, Baron Cuvier was a French naturalist who is known as the founder of the field of paleontology, as well as the founder of comparative anatomy.

Cuvier was born in Montbeliard, near Basel. Although a French town, Cuvier's birthplace at that time belonged to the Duchy of Wërttemberg. Cuvier was an academically inclined young man and, because his family lived in near-poverty, he accepted the offer to study for free at the Karlsschule in Stuttgart, Germany. He graduated at eighteen, returned home, and then found employment as a tutor in Normandy. While working in Normandy, he familiarized himself with the marine creatures he found on the beach, which he dissected and drew in detail. While doing so, he referred to Aristotle's ideas of comparing different animal structures, Carl Linnaeus's System of Nature and Buffon's Natural History of Animals. His impressive marine animal drawings came to the attention of Geoffroy Saint-Hilaire, and eventually led to Cuvier's appointment as assistant professor of comparative anatomy at the Museum of Natural History in Paris. Under Napoleon's regime, Cuvier became inspector General in the Department of Education and contributed to significant education reform in France. After Napoleon's fall, Cuvier retained his position and became an accepted authority in science and education, and earned several promotions which include a professorship at the Collège de France and permanent secretary for the Academy of Sciences. Cuvier died in 1832 of cholera, during the first major epidemic of that disease in Europe.

Prior to Cuvier, anatomists such as Louis Daubenton, Johann Friedrich Blumenbach, and Petrus Camper posited the human being as the fundamental form to which all other living creatures were compared. Cuvier, however, decided to create an objective system of comparative anatomy based on observation. His initial field of research was marine animals, particularly mollusks, worms, and various fishes. Later, he extended his investigations to vertebrates in general. The conceptual framework of Cuvier's research was a systematic method of comparative anatomy. According to Cuvier, living beings exhibit certain distinctive anatomic features that enable the scientist to place an individual specimen in the larger context of a general anatomic system. For example, one can make significant generalizations by observing individual features such as dental structure, foot structure, skull shape, etc. Cuvier's comparative research, which expanded from the study of vertebrates to include the entire animal kingdom, was presented in his work The Animal Kingdom, Distributed According to Its Organization (1817). While Cuvier's work did not contribute any new facts to the science of anatomy, his method earned him high praise and esteem in the scientific community.

An important element of Cuvier's methodology is his correlation theory, which posits the functional interdependence of particular organs within an in individual organism. For example, as Cuvier observed, carnivorous animals possess certain distinctive features that clearly separate them from, say, herbivores. These features include sharp teeth, a certain jaw structure, a digestive system adapted to meat, acute eyesight, sharp claws, powerful and swift locomotion, etc.

In Paris, which is in a calcareous area, Cuvier applied his comparative method to study fossils. In his carefully organized excavations, particular attention was paid to the specific location, position, and placement of the discovered fossils. In addition, using his correlation theory, he developed a reconstruction method that enabled researchers to identify incomplete skeletons. Furthermore, in order to validate a particular hypothesis concerning the identity of an incomplete skeleton, Cuvier would compare the extinct animal to its closest living relative, in an effort to complete the puzzle. These investigations were described in his seminal Investigations on Fossil Bones (1812), establishing Cuvier as the founder of modern paleontology. Using his comparative method, with particular emphasis on dentition and bone structure Cuvier was able to demonstrate that the two types of elephant, Indian and African, classified as examples of one species, in reality constituted two distinct species. In fact, Cuvier found that the extinct mammoth is closer to the Indian elephant than the two existing elephant species are to each other. Extending his research on elephants to Pachydermata in general, Cuvier studied both existing and extinct forms, identifying several new genera, including Palaeotherium and Dinotherium. In addition, he provided the first scientific description of the American giant sloth and named the pterodactyl.

Cuvier, like many of his colleagues, puzzled over the seemingly mysterious fact that animal forms changed through history. However, unlike some his colleagues, who approached the issue with extreme circumspection, Cuvier decided that species do not change. "The immutability of species," wrote Nordenskiöld, "is to Cuvier's mind an absolute fact." In order to explain why certain species were extinct and why fossils of some extinct creatures were unrecognizable from modern creatures, Cuvier invoked the catastrophism theory, which posits that a "new" species appear after the extinction, due to a violent upheaval (such as an earthquake) of its "old" counterpart. Thus, for example, Cuvier denied the existence of human fossils, asserting that, for example, lion fossils and lions in their present form represent two distinct species. Realizing the absurdity of the idea that species emerged out of nothing following a catastrophe, Cuvier attempted the explain the continuity of life by positing a type of near-extinction, which would allow the survival of small populations of a particular species, positing, as Cassirer has remarked, an evolution by analogy, whereby a particular species would be replaced by its new analogue, which to his mind seemed more reasonable than the notion of gradual evolution.

Cuvier's views of classification and evolution were vigorously opposed by several of his prominent contemporaries, who found his systematic philosophy, particularly his adamant insistence of four ground-plans, dogmatic. For example, Geoffroy Saint-Hilaire, who engaged Cuvier in a lengthy polemic, maintained that, because life manifests itself on the basis of a fundamental, indivisible impulse, Cuvier's claim that creatures emerging from different ground plans that cannot be compared does not reflect the true nature of the animal world. Accused by his critics for speculative dogmatism, Cuvier nevertheless, as Cassirer has written, defended his views on the basis of empirical research. As scholars have observed, the polemic between Cuvier and Saint-Hilaire was never resolved owing to the both antagonist defended points of view, which, while seemingly opposed, contributed, as complementary views, to the progress of life sciences and Earth sciences.