Baron Georges Léopold Cuvier

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Baron Georges Léopold Cuvier

The French zoologist and biologist Baron Georges Léopold Cuvier (1769-1832) made significant contributions in the fields of paleontology, comparative anatomy, and taxonomy and was one of the chief spokesmen for science in postrevolutionary France.

Georges Léopold Cuvier was born on Aug. 23, 1769, in Montbéliard, a small, French-speaking town in the duchy of Württemberg, where his father was commandant of the local artillery. Cuvier was christened Jean Léopold Nicolas Frédéric, but after the death of his elder brother, Georges, in 1769, he was known as Georges. His parents hoped that he would keep up the family tradition of one son from each generation training for the Lutheran ministry, but instead Cuvier attended the Académie Caroline in Stuttgart (1784-1788), studying commerce and economics, police and public administration, law, and chemistry, mineralogy, botany, and zoology. He was active in the school's natural-history society and studied privately under K. F. Kielmeyer, one of the early German Naturphilosophes.

Soon after graduation, Cuvier became tutor to the D'Hericys family, Protestant nobles who lived in Normandy, with whom he remained until 1793. When his home district was absorbed into France that year, Cuvier became a French citizen. He served as secretary of Becaux-Cauchois until 1795 and then moved to Paris. He obtained a position as assistant to the professor of comparative anatomy at the Jardin des Plantes (later the National Museum of Natural History) and began his first course of lectures in comparative anatomy there in December. At the same time, he was elected a member of the anatomy and zoology section of the Institut de France. In 1800 Cuvier was appointed secretary for the physical sciences section of the Institute and professor of general natural history at the Collège de France.

From 1800 until his death Cuvier was very active both as a research scientist and as a scientific educationalist and administrator. Moreover, under successive French governments he held various offices of state and investigated and reported on state problems. These concerned not only science but also religion, as Cuvier remained a devout Lutheran throughout his life. In 1802 Napoleon appointed him inspector general of higher schools; later he was responsible for reorganizing education in Italy, the Netherlands, and other conquered territory beyond the borders of France. Also in 1802, he became professor of comparative anatomy at the Jardin des Plantes. The following year Cuvier was appointed one of the two permanent secretaries of the Académie des Sciences of the Institut de France. In 1807-1808 he prepared a special report for Napoleon on the development of science since the French Revolution.

Cuvier married Anne Marie Coquet de Trazaille, a widow with four children, in 1804. Of their own four children, only one daughter survived infancy.

In the 15 years after his arrival in Paris, Cuvier was at his most active in scientific research. He published major works on animal classification, fossils, theoretical paleontology, natural history, and comparative anatomy. His later life was taken up more and more by administrative and state matters, so that although he continued to publish much scientific work it did not have the originality of his earlier publications.

Cuvier was appointed a councilor of the Napoleonic University of France in 1808. He was a member of the Council of State from 1813 until his death. In 1817 he became vice president of the Ministry of the Interior; the following year he was elected a member of the Académie Française. In 1820 he was made a baron. From 1821 to 1827 Cuvier was chancellor of the University of France. In 1822 he was appointed grand master of the Faculties of Protestant Theology in the University of Paris, and in 1826 he was made a grand officer of the Legion of Honor. In 1828 he became director of all non-Catholic churches in France. In 1831 Louis Philippe raised Cuvier to the peerage. He died on May 13, 1832.

In public life Cuvier was, above all, concerned for good order. His generally conservative attitudes were at least partly a response to the chaos and breakdown of social order which he had experienced in the years of the French Revolution. As a scientist who did not depend on his political activities for recognition or status, Cuvier was more concerned with the good working of the various institutions of French life than with party and personality politics. As an adviser to the state on education, he strongly opposed the influence of the Roman Catholic Church and particularly that of the Society of Jesus. He supported secular education and tried to see that it included a fair proportion of natural science.

Contributions to Science

Cuvier's life spanned the period during which it became possible in France, for virtually the first time, to make a profession of science. He was not trained to be a scientist, as professional training in the sciences was virtually unknown when he went through college. He and his colleagues took part in setting up the first such courses in France.

Soon after Cuvier arrived in Paris in 1795, he took up the problem of the classification of animals and together with a colleague published a very important paper on the classification of mammals. Cuvier was concerned with the practical question of which features of an animal should be used to distinguish it from other species. Underlying the need for a practical system of classification was his search for a theoretical justification for the taxonomic system he advocated. Throughout his life he continued to be concerned with the problem of classification.

In 1798 Cuvier published an introductory textbook in natural history, Tableau élémentaire de I'histoire naturelle des animaux, which became the standard text for French colleges. He was also aware of the need for a comprehensive reference book and manual in zoology, and in 1817 he published the four-volume Le Règne animal. …, whose full title, "The Animal Kingdom, arranged according to structure, in order to form a basis for zoology, and as an introduction to comparative anatomy," well describes the functions he hoped it would serve. The work was revised and reissued in five volumes in 1829-1830; by then it had been translated into many languages and had become a standard zoological reference throughout the world.

Cuvier's lectures in comparative anatomy were collected and edited by two of his assistants and published in five volumes between 1800 and 1805 under the title Leçons d'anatomie comparée. His concern for classification led him to pay special attention to the anatomy of the various systems of organs as he developed his own theories about which systems should be used for purposes of classification.

Another area in which Cuvier carried out major research was the study of fossils. He believed that a study of fossil animals would clarify geological theories about the development and history of the earth. From 1796 until 1812 he published a series of papers on the fossil remains of animals and their significance for geology; they were collected in four volumes in 1812 as Recherches sur les ossements fossiles de quadrupèdes.

Appended to this collection was a summary of Cuvier's views about the formation of the different surface layers of the earth, which was later revised and entitled Discours sur les révolutions de la surface du globe. In this work he put forward the view that the earth had suffered successive catastrophes in the form of floods which had swamped all but the highest mountains. This view of geological history became known as catastrophism; it was opposed by the uniformitarians, who believed that the surface structure of the earth was due to ordinary everyday causes, which continued to be active up to the present, and not just catastrophic events.

Cuvier and Classification

By the end of the 18th century biologists were faced with an enormous problem of classification because of the large number of new animal and plant specimens collected from different parts of the world. The ideas and practices which had been developed from the time of Carl Linnaeus were no longer satisfactory. One aspect of the problem of classification was its philosophical basis. For some naturalists a system of classification was merely an arbitrary but practical way to distinguish between and learn about different animals. Others, however, argued that there was a "natural" system of classification which indicated some sort of real relationship between the animals in the different parts of the system.

Cuvier believed that animals could be classified into different kinds and that each kind of animal could be represented for classification purposes by an ideal "type." The animal type would include all the characteristics distinguishing it from other types. According to Cuvier, types would not change from generation to generation. He arrived at the mature statement of his view on classification in 1812. He classified all animals into four main branches (embranchements) according to the construction of their nervous system; he used the nervous system because he considered it the most important system physiologically or functionally. Less important, or subordinate, systems of characteristics were used to create classificatory subdivisions within the four branches. He called this method of classification the principle of the subordination of characters.

Cuvier justified his system of classification philosophically by arguing along Aristotelian lines that animals were distinguished from other orders of creation by their ability to sense and perceive things. Hence, he argued, the most important, or the most "animalistic," physiological system was that responsible for sensation, namely, the nervous system. He then based his system of classification of animals on the differences of their nervous system. "In considering the animal kingdom from this point of view," he said, " … I have found that there exist four principal forms, four general plans, upon which all of the animals seem to have been modeled …." (quoted in William Coleman, 1964). These four models, or branches, of the animal kingdom were the Vertebrata, the Mollusca, the Articulata, and the Radiata.

This new system of classification, together with the encyclopedic works which Cuvier based on it, greatly helped the naturalists of his day to assimilate and understand all the new information about animals. Despite its success, however, his system was immediately challenged by those whose philosophy of biology differed considerably from his own.

Theory of Evolution

Cuvier did not live to see Charles Darwin propound his theory of evolution by natural selection, yet he is frequently portrayed as one of the most important anti-evolutionary figures in the history of biology. This reputation arose largely from the clash with his contemporaries Jean Baptiste de Lamarck and étienne Geoffroy Saint-Hilaire, who supported evolutionary ideas.

Lamarck taught that there was no such thing as a constant species. He held that the more individual animals he examined, the less certain he became about saying that there were definite boundaries between the forms of different species. Moreover, he put forward the view that the form of species changed from generation to generation through the effects of use or disuse on the various parts of animals. The usage of different organs would change because of changes in the environment. Lamarck pointed to the fossil remains of animals as evidence supporting his theory. Among the fossils were animal forms no longer existing on earth. These, he claimed, were ancestor to the present array of animals.

Cuvier agreed with Lamarck that there was much variation among animals. But he held that most of the variation was among the secondary, or subordinate, characters of animals and that these were not important for the functional integrity of the animals. Organs such as the heart and lungs and the nervous and digestive systems—which were important for the functional integrity of an animal—varied slightly and within very definite limits in the one species, according to Cuvier. However, his strongest argument was that Lamarck could produce no evidence of the transformation of species, whereas Cuvier could show, from evidence recently brought back to France by Napoleon's army, that domestic animals had not changed since the time of the ancient Egyptians. Furthermore, he showed that the disappearance of various fossil animals was due to their becoming extinct rather than transforming into new species.

Both Lamarck and Geoffroy Saint-Hilaire supported the idea that all animals could be arranged into a "great chain of being" from the simplest to the most complex and that this was shown by certain similarities in the structures of all the species. Cuvier also strongly opposed this idea, which was used by some evolutionists. For him the four branches of the animal kingdom which he had postulated could in no way be likened to each other.

Cuvier's arguments against evolution fitted very well into his own conservative philosophy of biology and with his Christian faith, which supported the view that all present species must have descended from a common pair of ancestors created by God at the beginning of the world. Because his brilliant biological system fitted so well with the conservative point of view in both science and theology, his arguments against the evolution theory have been used countless times since his death.