Darwin's reefs, upon which he almost foundered

Despite the rain on my window, it's a fine day indeed, with many wonderful celebrations of Darwin's 200th ringing throughout the blogoshere.

Most of these, naturally, focus on Darwin's theory of evolution and its many implications and reverberations. I much admire that theory. But what I find most fascinating about Darwin is not his theory of evolution but his method of empiricism. For as vital as was Darwin's theory of evolution was, his impact on how we view ourselves is rivaled by his impact on how we view and do science.

This and many other perverse oddities struck me when I was researching Reef Madness, my book about Darwin's coral reef theory. Darwin hatched his theory of coral reef formation very early, before his method was mature, and he published it quicklyi. Then, late in his life, when it seemed the core of what he proposed was finally safely accepted, he had to defend this first, most beloved, and in many ways most brilliant theory of his -- and with it, the principles of his method -- from a sustained and formidable assault.

The story of this challenge reveals thing about Darwin's method, and about the essential questions of philosophy and method that tortured the 19th century, that are often obscured in our consideration of his work on evolution. To look at this story is to meet a Darwin who is less sure, more vulnerable, and more clearly caught in, rather than driving, the era's difficult reassessment of how to describe nature and its mechanisms. It is also to see him wield, very early on, the method and even the generative insights that drove his evolutionary theory. Like his later theory of natural selection, Darwin's theory of coral reefs imaginatively explained an array of forms with a vision of incremental change through time. As I put it in the book,

Thematically, formally, and even psychologically, Darwin's coral reef theory served almost as direct progenitor of his species theory. As perhaps nothing else could have, it prepared him for the conceptually similar but more difficult work on evolution and natural selection. He seems to have needed this dry run -- a theoretical foray into the relatively tame territory of rocks and reefs -- before pursuing a similar argument on the more perilous species question.

This morning, on the radio, someone referred to "the islands that inspired Darwin's theory of evolution." They meant the Galapagos, of course. But even before he went to the Galapagos, when he was still on the west coast of South America, Darwin, pondering charts of the Pacific coral islands well to the Galapagos's west, had hatched his coral reef theory. (As I said, scandalously deductive.) There's a sense in which it was not the Galapagos but the coral isles further west (considered from South America) that inspired

So what was "the coral reef problem" that occupied Darwin and so many other great scientists of his era?

The problem was how the "huge beautiful forms" of the Pacific coral archipelagos -- islands, reefs, atolls --

composed of the skeletons of tiny animals that could survive only in shallow water, came to rise on foundations that emerged from the Pacific's greatest depths.How did so many of these platforms - thousands of them reaching just shy of the surface - come to be? Though this mystery drew the attention of great scientists for decades, a satisfactory answer proved elusive. Today, of course, the main argument about coral reefs is how to save them, and only scientists might recall the debate that once raged about their origin. But in the 1800s, particularly from the 1870s onward, the "coral reef problem," as it was known, was one of the most difficult and contentious in science.

Why?

The coral reef debate reprised in many ways the evolutionary debate, engaging many of the same figures and ideas. The coral reef problem did not concern species origin or humankind's descent. But it posed the evolutionary debate's confounding questions about the importance of evidence, the proper construction of theory, and the reliability of powerful but abstract ideas.

These questions were fundamental to science's self-definition then and now. Darwin handily won the dispute over method in the fight over his evolution theory, for he held the stronger evidentiary hand -- his mountain of evidence demonstrating natural selection simply overwhelmed the creationist narrative: Data trumps pretty story, especially when the data itself tells a compelling story. But his use of the same method on the coral reef question -- just as imaginative but less robustly supported -- left him standing on shakier ground. Suddenly he had the pretty story and his opposites the pile of evidence. His genesis of the coral reef t heory early on and his defense of it later dramatically both the era's perverse demands and difficulties -- and the challenge, which he eventually met, of forging a scientific method that was both creative and rigorous.

In the next few days I'll flesh this story out and hit some other oddities of what I found researching it: My amazement, for instance, at finding that during the Beagle voyage and for well afterward, Darwin was more geologist than zoologist: The man took 400 notes on zoology during the Beagle voyage, but 1400 on geology, and the majority of his publications in his first five years back were about geology. We'll see him hatch the coral reef theory; fall flat on his face when he commits "one long, gigantic blunder" in the Scottish Highlands; and sweat late in his life as one of the century's most formidable oceanographers -- a friend, a Darwinist, but the son of an old and ferocious foe -- challenged the theory that gave him more pleasure, he said, than any other he had ever hatched.