A reason for loving Cuvier (2008.10.1[Wed])

 

I recently obtained a pictorial atlas of zoology by George Cuvier. To tell the truth, my wife bought it, so it belongs to her, but thanks to it I now have an extra dimension to my bibliomania. Which is almost too scary to think about. I also finally made a serious reading of Tony Appel's "The Cuvier-Geoffroy Debate," *1(until now I'd only browsed through it), which I did in order to gain a better understanding of Robert Richards' biography of Haeckel, "The Tragic Sense of Life," and Haeckel's own writings. When you get into this kind of research, it's like beginning a journey in which each new discovery leads to a new quest; my reading list never seems to get any shorter. In fact, I just picked up some novels by Balzac and books on the French Revolution. Who knows where those will lead me...

 Appel's book is a masterpiece both in the original and in translation, a must-read for anyone interested in the pre-Darwinian history of evolutionary biology. This type of work typically tends to be heavy on personalities and historical background, and light on the scientific nitty-gritty, but "The Cuvier-Geoffroy Debate" is a welcome exception to that rule. The translator is also a real pro, and gives his full attention to the minutiae of anatomical discussions throughout. In fact, on reading this, I discovered a number of errors in understanding, which, I'm ashamed to say after reading this magisterial work, I had allowed to creep into my own writing. That will teach me to rely on secondary sources. For the same reason, one also has to be careful about reading only works published in America or the UK, which come packed with their own historical and ideological baggage. That said, trying to work out the historical stage on which a particular scientific debate played out can be tricky for those of us who are not historians, which involve be a thesis' worth of research. Keep that in mind when reading the interpretation of Cuvier's thought outlined below, as it is based on my own guesswork more than it is on the primary literature, meaning there's some risk of error or skewed exegesis attributable to the secondary sources.

 Whatever the case, understanding Cuvier is no cakewalk. He may be known as the father of biology, but there is no book, either original or in translation, on him in Japanese. There are mountains of works on Darwin, and you can even find them on such figures as Buffon, Linnaeus and Gesner. Haeckel, though, has the same problem as Cuvier - no one in Japan has been able to give the proper due to these giants whose names nonetheless still appear in our high school textbooks. Cuvier and Haeckel. Have scientists ever been more misunderstood and remembered for the wrong reasons than these two?

 Cuvier is typically portrayed solely as the anti-evolutionary advocate of episodic catastrophism (he branded these "revolutions"), as the forerunner to Darwin, and as Lamarck's mortal foe. All true, of course, but he is also the man who laid the firm taxonomical and physiological foundations of comparative biology that were later to serve as the cornerstone of evolutionary theory. During his tenure as a professor at the Natural History Museum in Paris, he showed a spectacularly wide range of interest and activity, classifying countless animal species in a system of natural history that has fared remarkably well over time. Lamarck may have given us the far-ranging system for organizing animal diversity into vertebrates and invertebrates that we still use today, but it was Cuvier who first saw that there were four morphological plans within the invertebrate phyla, which he classed as the four primary embranchements.

 Geoffroy, rival to Cuvier in Appel's "Debate," was certainly an able scholar but no match for him as a student of natural history. You might say he was closer in spirit to the evo-devo scientists of modern times. People tend to think of him as a pure morphologist, but his theories were little different than the Urbilaterian theory current today. As for formalism, it would be fairer to say that it truly blossomed on Germany.

 Geoffroy's theory sought to organize all of Cuvier's four embranchements within a single all-encompassing "form (unity of type)." Which at least is easy to understand. If it had allowed for biological evolution, it would seem to be a natural way of thinking. Cuvier's response to this monolithic system was firmly grounded in logic and intellect, but yet his point remains unclear. Despite his taxonomy of animals into four discrete body plans, Cuvier saw an underlying "unity" within the vertebrates, as constrained by their morphological limits, and seemed to accept the effectiveness of the pure morphological approach. He argued that "a specific body plan is organized to perform a specific physiological function, no more and no less," but it is also the fact that species from different groups sometimes converge for reasons of functional necessity. For Cuvier, the dynamism implicit in a system of changing universals giving rise to the protean diversity of animal form was intolerable. Seen in that light, the source of the difficulties in his reasoning becomes easy to see.

 At the end of the 18th century, the young Cuvier had already resolved to dedicate himself to natural history, devouring every text available, and building a formidable body of knowledge. Then, revolution came to France. Several scientists were guillotined merely for having served as bureaucrats, and the professoriate was herded out alongside the nobility, and he could only watch as the once-proud French culture and the academie were reduced to ruins. It is no exaggeration to say that the French Revolution beggared France's intellectual regime. Cuvier never bought into the democracy for and by the masses that had been stirred by that great Ressentiment, believing that sound conservatism and authority were needed to undergird any great intellectual tradition. In a similar vein, he saw species as immutable - "all individuals within a species are the descendants of a single ancestor, among which change never occurs." In his scientific vision, transitions and change were anathema, while natural history of the sort involving exhaustive taxonomies of never-changing species held pride of place. It was this belief that led him to propose his rigidly universal scheme. In this light, the "revolutions" of his catastrophism reflect the trauma of Revolution that wracked the Ancien Regime. His was to be a system in which no trace of evolution or change would be found. And rife with contradictions as it inevitably was, one that would lead to his confrontation with Geoffroy...

I am willing to forgive Cuvier his elitism and authoritarian ways, and to remember him rather for his love of zoological diversity and natural history, and as the epitome of those who so deeply admired France's grand old tradition, in all its assiduousness, its love of study and isolation, its fine-toothed precision and accuracy of seeing, even its diffidence and anxiousness as well. Young scientists today must share in being buffeted by societal forces beyond their control. For Cuvier, species were ordained to be immutable as his science. And thus I choose to understand him as a man who, despite his disappointments, played out so ably his role as a scientist, and a man of the world as he wished it could be.