Before we finally made it to the coast, where a support vessel was frantically looking for us, one member of the expedition was delirious and close to death. He was subsequently hospitalized for five days, back in the United States, and it took him more than a month to recover.
The day was unusually hot, and Tye, after a few hours of hiking, felt the onset of heat exhaustion and asked me to take over the lead. Using a machete to help clear our way through the brush, I too became heat exhausted, and began to vomit. Heat exhaustion turned out to be the least of my problems.
I had inadvertently cut the branch of an overhanging manzanillo tree, whose apples are poison to humans but beloved by tortoises. The sting from the sap was almost unbearable, and dousing my eyes with water did nothing to help.
For the next seven hours I was nearly blinded and could open my eyes for only a few seconds at a time. As I walked back to our campsite, five hours away, I often had to balance, with my eyes shut, on huge boulders in a dry riverbed, and on the edge of lava ravines. Those were the most painful seven hours I have ever spent. Legend has it that Darwin was converted to the theory of evolution, eureka-like, during his visit to the islands.
How could he not have been? In retrospect, the evidence for evolution seems so compelling. I owe this historical insight to a curious fact—Darwin was a lousy speller. We know, moreover, from the complete record of his unpublished scientific notes that he was personally dubious about evolution. According to creationist theory, species were a bit like elastic bands. He and his servant did take back to England, as pets, two baby tortoises.
Those juvenile tortoises further misled Darwin, because differences among subspecies are evident only in adults. Not realizing the importance of tortoises for the theory he would eventually develop about the origins and diversity of living things, Darwin and his fellow shipmates ate their way through 48 adult tortoise specimens and threw their shells overboard. They have become one of the most famous cases of species adapting to different ecological niches. For example, Darwin thought the cactus finch, whose long, probing beak is specialized for obtaining nectar from cactus flowers and dodging cactus spines , might be related to birds with long, pointed bills, such as meadowlarks and orioles.
He also mistook the warbler finch for a wren. Not realizing that all of the finches were closely related, Darwin had no reason to suppose that they had evolved from a common ancestor, or that they differed from one island to another. One of my most unexpected discoveries in the Darwin archives was the piece of paper on which Darwin recorded his crucial meeting with Gould.
Stunned by the realization that evolving varieties could break the supposedly fixed barrier that, according to creationism, prevents new species from forming, he quickly sought to rectify his previous collecting oversights by requesting island locality information from the carefully labeled collections of three Beagle shipmates.
The birth of the Darwinian revolution was a highly collaborative enterprise. The case for evolution presented by this shared ornithological evidence nevertheless remained debatable for nearly a decade. Darwin was not entirely convinced Gould was right that all the finches were separate species, or even that they were all finches. At Cambridge he met a prime mover in the developing science of Geology, Adam Sedgwick, whom he accompanied on field trips to North Wales and other places. He also met and learned a great deal from Professor Henslow, a wonderful teacher and friend, with whom he chased moths and butterflies across the fens with a big net, and learned to classify plants.
In , when Darwin was only 22, Henslow learned of the imminent departure of a Royal Navy survey ship, HMS Beagle, which was in need of a naturalist. Would Charles like to go? Charles jumped at the opportunity. His father reluctantly gave permission, and the ship sailed from Plymouth on 27 December The main object was to make good naval charts of parts of South America, which was the speciality of Captain Fitzroy, who was also rather fundamentalist in his religious views.
It was while they were surveying the Galapagos Islands that Darwin made many observations which eventually led to his theory of evolution by natural selection, although he barely grasped the significance at the time.
And so it was: the ten rocky islands were home to many plants and animals that were like those of neighbouring South America , but with distinct differences. Half the species of birds living on these islands occurred nowhere else on the planet.
Each island had its own species. How had this come about? Could this extraordinary variety really be explained by the idea that God had created all the species on Earth in six days? And while the public disagreement between ecclesiastical and scientific authorities did not end in the s, religious thinkers became more wary of directly challenging evolution on scientific grounds.
In the late 19th and early 20th centuries, churches instead focused much of their energy on resisting the idea that man had evolved from lower animal orders and hence had no special place in creation or, for that matter, a soul. Indeed, while some churches, including the Catholic Church, eventually accepted evolution as a God-directed mechanism of biological development, none questioned the role of God as the sole creator of man.
By the time of his death, in , Darwin was considered the greatest scientist of his age. Moreover, the very church his theory had challenged accorded him a full state funeral and burial in Westminster Abbey, near the grave of Sir Isaac Newton. Indeed, his interment in the abbey was seen by some contemporaries as symbolic of an uneasy truce between science and religion in Britain. About Pew Research Center Pew Research Center is a nonpartisan fact tank that informs the public about the issues, attitudes and trends shaping the world.
It conducts public opinion polling, demographic research, media content analysis and other empirical social science research. Pew Research Center does not take policy positions. It is a subsidiary of The Pew Charitable Trusts. Newsletters Donate My Account. Research Topics.
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