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Portrait of Charles Darwin (J. Cameron)

The Evolution of Charles Darwin

A creationist when he visited the Galápagos Islands, Darwin grasped the significance of the unique wildlife he found there only after he returned to London

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From the nine times I have made the 5,000-mile journey to the Galápagos Islands, to follow in Charles Darwin’s footsteps, the most enduring impression I have gained is of life’s fragility. The minute a person steps off any of the tourist trails created by the Galápagos National Park Service and heads into the untamed interior of one of these islands, there is the risk of death under the intense, equatorial sun. On Santa Cruz Island, where the Charles Darwin Research Station is located, 17 people have disappeared since 1990. Most were subsequently found alive after having become hopelessly lost in dense underbrush and rugged volcanic terrain. But some perished. One was a young Israeli tourist who lost his way in Santa Cruz’s Tortoise Reserve in 1991. Amassive, two-month search failed to find him. In fact, some of the searchers themselves became lost and had to be rescued. In the end, fishermen discovered the young man’s body. A former Israeli tank commander, he had been in top physical condition, yet had managed to go only six miles before succumbing to the searing heat and lack of fresh water. A sign in the Tortoise Reserve says bluntly: “Stop. Do not go beyond this point. You could die.”

This is the deceptively treacherous world of sun-baked lava, spiny cactus and tangled brushwood into which Charles Darwin stepped in September 1835, when he reached the Galápagos Islands with fellow crew members of the HMS Beagle. The Beagle’s captain, Robert FitzRoy, described the barren volcanic landscape as “a shore fit for Pandemonium.” At 26, Darwin had come to the archipelago, which straddles the Equator some 600 miles west of Ecuador, as part of the Beagle’s five-year mission to survey the coast of South America and to conduct a series of longitudinal measurements around the globe. Darwin’s five-week visit to these remarkable islands catalyzed the scientific revolution that now bears his name.

Darwin’s revolutionary theory was that new species arise naturally, by a process of evolution, rather than having been created—forever immutable—by God. According to the well-established creationist theory of Darwin’s day, the exquisite adaptations of many species—such as the hinges of the bivalve shell and the wings and plumes on seeds dispersed by air—were compelling evidence that a “designer” had created each species for its intended place in the economy of nature. Darwin had wholeheartedly accepted this theory, which was bolstered by the biblical account in Genesis, until his experiences in the Galápagos Islands began to undermine this way of thinking about the biological world.

The Galápagos Islands were formed by volcanic eruptions in the recent geological past (the oldest of the islands emerged from the ocean just three million years ago), and Darwin realized that the remote setting must have presented life with a new beginning. “Seeing every height crowned with its crater, and the boundaries of most of the lava-streams still distinct, we are led to believe that within a period, geologically recent, the unbroken ocean was here spread out,” he wrote in his Journal of Researches. “Hence, both in space and time, we seem to be brought somewhat near to that great fact—that mystery of mysteries—the first appearance of new beings on this earth.”

How, Darwin asked himself, had life first come to these islands? “The natural history of these islands,” he later pointed out, “is eminently curious, and well deserves attention. Most of the organic productions are aboriginal creations, found nowhere else.” Yet all of the creatures showed a marked relationship with those from the American continent. The novel Galápagos species, Darwin reasoned, must have started out as accidental colonists from Central and South America and then diverged from their ancestral stocks after arriving in the Galápagos. As he traveled from island to island, Darwin also encountered tantalizing evidence suggesting that evolution was proceeding independently on each island, producing what appeared to be new species.

Other evidence, from the South American continent, showed that species did not seem to be stable across either geographic space or the deep reaches of paleontological time. But the particularly compelling evidence from the Galápagos Islands catapulted Darwin and life science into the modern age. He subsequently added to his daring endorsement of evolution the crucial insight that species evolve by means of natural selection: variants that are better adapted to their environments are more likely to survive and reproduce. When he finally published On the Origin of Species by Means of Natural Selection in 1859, Darwin’s revolutionary theories not only recast the study of life but also turned the Galápagos Islands into hallowed scientific ground.

More than three decades ago, I became fascinated by Darwin’s life, and especially by his historic voyage around the world. When evolutionary biologist Edward O. Wilson, whose undergraduate course I was taking at Harvard, learned of my interest, he suggested that I go to the Galápagos Islands, and he helped fund a documentary about Darwin’s voyage. My first trip, in 1968, was two years before the beginning of organized tourism in the Galápagos. Just getting to the islands
was a challenge. Our expedition flew from Guayaquil, Ecuador, in a PBY, an amphibious, twin-engine patrol plane dating back to the World War II era. We sat in seats made of mesh nets. There were numerous holes in the plane’s undercarriage, through which I could see all the way to the ocean below. The impression these starkly beautiful islands made upon me was indelible (the volcano that forms the island of Fernandina put on a spectacular eruption during our visit).

Eight expeditions later, I continue to be drawn to these islands in an effort to document their extraordinary impact on Darwin, as well as to study ecological changes since Darwin’s day. With the advent of organized tourism, much has changed. Now, two to four passenger planes fly each day to the Galápagos, bringing a total of about 100,000 tourists a year. Puerto Ayora, home to the Charles Darwin Research Station, is a booming tourist stop with a population of about 15,000 people, almost ten times the number that resided there during my first visit. As tourists enjoy their organized cruises around the islands, they are confined to 60 localities, carefully selected by the National Park Service, and are required to stay on clearly marked paths that keep them out of harm’s way.

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