From the cover
Introduction
REEF, CITY, WEB
. . . as imagination bodies forth
The forms of things unknown, the poet’s pen
Turns them to shapes and gives to airy nothing
A local habitation and a name.—SHAKESPEARE, A Midsummer Night’s Dream, V.i.14-17
Darwin’s Paradox
April 4, 1836. Over the eastern expanse of the Indian Ocean, the reliable northeast winds of monsoon season have begun to give way to the serene days of summer. On the Keeling Islands, two small atolls composed of twenty-seven coral islands six hundred miles west of Sumatra, the emerald waters are invitingly placid and warm, their hue enhanced by the brilliant white sand of disintegrated coral. On one stretch of shore usually guarded by stronger surf, the water is so calm that Charles Darwin wades out, under the vast blue sky of the tropics, to the edge of the live coral reef that rings the island.
For hours he stands and paddles among the crowded pageantry of the reef. Twenty-seven years old, seven thousand miles from London, Darwin is on the precipice, standing on an underwater peak ascending over an unfathomable sea. He is on the edge of an idea about the forces that built that peak, an idea that will prove to be the first great scientific insight of his career. And he has just begun exploring another hunch, still hazy and unformed, that will eventually lead to the intellectual summit of the nineteenth century.
Around him, the crowds of the coral ecosystem dart and shimmer. The sheer variety dazzles: butterflyfish, damselfish, parrotfish, Napoleon fish, angelfish; golden anthias feeding on plankton above the cauliflower blooms of the coral; the spikes and tentacles of sea urchins and anemones. The tableau delights Darwin’s eye, but already his mind is reaching behind the surface display to a more profound mystery. In his account of the Beagle’s voyage, published four years later, Darwin would write: “It is excusable to grow enthusiastic over the infinite numbers of organic beings with which the sea of the tropics, so prodigal of life, teems; yet I must confess I think those naturalists who have described, in well-known words, the submarine grottoes decked with a thousand beauties, have indulged in rather exuberant language.”
What lingers in the back of Darwin’s mind, in the days and weeks to come, is not the beauty of the submarine grotto but rather the “infinite numbers” of organic beings. On land, the flora and fauna of the Keeling Islands are paltry at best. Among the plants, there is little but “cocoa-nut” trees, lichen, and weeds. “The list of land animals,” he writes, “is even poorer than that of the plants”: a handful of lizards, almost no true land birds, and those recent immigrants from European ships, rats. “The island has no domestic quadruped excepting the pig,” Darwin notes with disdain.
Yet just a few feet away from this desolate habitat, in the coral reef waters, an epic diversity, rivaled only by that of the rain forests, thrives. This is a true mystery. Why should the waters at the edge of an atoll support so many different livelihoods? Extract ten thousand cubic feet of water from just about anywhere in the Indian Ocean and do a full inventory on the life you find there: the list would be about as “poor” as Darwin’s account of the land animals of the Keelings. You might find a dozen fish if you were lucky. On the reef, you would be guaranteed a thousand. In Darwin’s own words, stumbling across the ecosystem of a coral reef in the...
