Georges Cuvier

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Georges Cuvier : biography

23 August 1769 – 13 May 1832

Age of reptiles

In 1800, Cuvier was the first to correctly identify in print, working only from a drawing, a fossil found in Bavaria as a small flying reptile, which he named the Ptero-Dactyle in 1809 (later Latinized as Pterodactylus antiquus)–the first known member of the diverse order of pterosaurs. In 1808 Cuvier identified a fossil found in Maastricht as a giant marine lizard, which he named Mosasaurus, the first known mosasaur. Cuvier speculated that there had been a time when reptiles rather than mammals had been the dominant fauna. This speculation was confirmed over the next two decades by a series of spectacular finds, mostly by English geologists and fossil collectors such as Mary Anning, William Conybeare, William Buckland, and Gideon Mantell, who found and described the first ichthyosaurs, plesiosaurs, and dinosaurs.

Principle of the correlation of parts

In a 1798 paper on the fossil remains of an animal found in some plaster quarries near Paris Cuvier wrote:

Today comparative anatomy has reached such a point of perfection that, after inspecting a single bone, one can often determine the class, and sometimes even the genus of the animal to which it belonged, above all if that bone belonged to the head or the limbs. … This is because the number, direction, and shape of the bones that compose each part of an animal’s body are always in a necessary relation to all the other parts, in such a way that – up to a point – one can infer the whole from any one of them and vice versa.

This idea is sometimes referred to as ‘Cuvier’s principle of correlation of parts’, and while Cuvier’s description may somewhat exaggerate its power, the basic concept is central to comparative anatomy and paleontology.

Principle of the conditions of existence

For Cuvier, the principle of the correlation of parts was theoretically justified by a further principle, that of the conditions d’existence, usually translated as "conditions of existence." This was his way of understanding function in a non-evolutionary context, without invoking a divine creator.See discussion in In the same 1798 paper he wrote:

if an animal’s teeth are such as they must be, in order for it to nourish itself with flesh, we can be sure without further examination that the whole system of its digestive organs is appropriate for that kind of food, and that its whole skeleton and locomotive organs, and even its sense organs, are arranged in such a way as to make it skillful at pursuing and catching its prey. For these relations are the necessary conditions of existence of the animal; if things were not so, it would not be able to subsist.

This principle later influenced the positivist philosopher Auguste Comte, and the physiologist Claude Bernard.

Chief scientific work

Comparative anatomy and classification

in 1798 Cuvier published his first independent work, the Tableau élémentaire de l’histoire naturelle des animaux, which was an abridgment of his course of lectures at the École du Pantheon, and may be regarded as the foundation and first statement of his natural classification of the animal kingdom.

In 1800 he published the Leçons d’anatomie comparée, assisted by A. M. C. Duméril for the first two volumes and Georges Louis Duvernoy for the three later ones.

Molluscs

Cuvier’s papers on the so-called Mollusca began appearing as early as 1792, but most of his memoirs on this branch were published in the Annales du museum between 1802 and 1815; they were subsequently collected as Mémoires pour servir à l’histoire et à l’anatomie des mollusques, published in one volume at Paris in 1817.

"When the French Academy was preparing its first dictionary, it defined "crab" as, "A small red fish which walks backwards." This definition was sent with a number of others to the naturalist Cuvier for his approval. The scientist wrote back, "Your definition, gentlemen, would be perfect, only for three exceptions. The crab is not a fish, it is not red and it does not walk backwards."