Georges Cuvier

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Georges Cuvier : biography

23 August 1769 – 13 May 1832

Cuvier also collaborated on the Dictionnaire des sciences naturelles (61 volumes, 1816–1845) and on the Biographie universelle (45 volumes, 1843-18??)

Scientific ideas and their impact

Opposition to evolution

He repeatedly emphasized that his extensive experience with fossil material indicated that one fossil form does not, as a rule, gradually change into a succeeding, distinct fossil form (see below). It is because of this fact and his understanding of animal anatomy and physiology, that Cuvier strongly objected to any notion of evolution. According to the University of California Museum of Paleontology (UCMP), "Cuvier did not believe in organic evolution, for any change in an organism’s anatomy would have rendered it unable to survive. He studied the mummified cats and ibises that Geoffroy had brought back from Napoleon’s invasion of Egypt, and showed that they were no different from their living counterparts; Cuvier used this to support his claim that life forms did not evolve over time."

He also observed that Napoleon’s expedition to Egypt had retrieved animals mummified thousands of years previously that seemed no different from their modern counterparts. "Certainly", Cuvier wrote, "one cannot detect any greater difference between these creatures and those we see, than between the human mummies and the skeletons of present-day men." Lamarck dismissed this conclusion, arguing that evolution happened much too slowly to be observed over just a few thousand years. Cuvier, however, in turn criticized how Lamarck and other naturalists conveniently introduced hundreds of thousands of years "with a stroke of a pen" to uphold their theory. Instead, he argued that one can judge what a long time would produce only by multiplying what a lesser time produces. Since a lesser time produced no organic changes, neither, probably, would a much longer time.

Cuvier was critical of the evolutionary theories proposed by his contemporaries Lamarck and Geoffroy Saint-Hilaire, which involved the gradual transmutation of one form into another. He repeatedly emphasized that his extensive experience with fossil material indicated that one fossil form does not, as a rule, gradually change into a succeeding, distinct fossil form. Instead, he said, the typical form makes an abrupt appearance in the fossil record, and persists unchanged to the time of its extinction. Cuvier attempted to explain this paleontological phenomenon (which would be readdressed more than a century later by "punctuated equilibrium") and harmonize it with the Bible, attributing the different time periods as intervals between major catastrophes, the last of which is found in Genesis. He was skeptical of the gradual mechanisms of change that Lamarck and Geoffroy Saint-Hilaire proposed. Moreover, his commitment to the Principle of the correlation of parts caused him to doubt that any mechanism could ever gradually modify any part of an animal in isolation from all the other parts (in the way Lamarck proposed), without rendering the animal unable to survive. In his Éloge de M. de Lamarck (Praise for M. de Lamarck), Cuvier noted that Lamarck’s theory of evolution

"rested on two arbitrary suppositions; the one, that it is the seminal vapor which organizes the embryo; the other, that efforts and desires may engender organs. A system established on such foundations may amuse the imagination of a poet; a metaphysician may derive from it an entirely new series of systems; but it cannot for a moment bear the examination of anyone who has dissected a hand, a viscus, or even a feather."

Cuvier’s claim that new fossil forms appear abruptly in the geological record and then continue without alteration in overlying strata was used by later thinkers to support creationism. The abruptness seemed consistent with special creation by God (although Cuvier’s finding that different types made their paleontological debuts in different geological strata clearly did not). The lack of change was consistent with the supposed sacred immutability of "species", but, again, the idea of extinction, of which Cuvier was the great proponent, obviously was not.