A Brief History of Creation (17 page)

Nearly everywhere he went in the Galápagos, Darwin found one particular bird species thriving.
^*
In his journal, he called them
thenka
, the Spanish name for birds he had encountered on the mainland in South America, which he had assumed to be mockingbirds. By the time he arrived on James, these birds were beginning to arouse a particular fascination in him. Two weeks earlier, the
Beagle
had stopped at the prison colony on Charles Island. The prisoners had claimed that each island was home to a different kind of tortoise that could be identified by its shell. The vice-governor said he could tell which island he was on by the tortoises alone. Darwin put little stock in the claims. James afforded plenty
of opportunity to study the tortoises up close, and they seemed identical to those he had already seen. But when Darwin began to notice little differences in the mockingbirds, he was reminded of his conversations on Charles. Those of each island seemed to have a beak distinctive from those of the others. Some beaks were much larger or smaller than others. Even the beaks' shapes varied, from narrow and pointed to wide and downward curved. By the time he arrived on James, he had begun recording the exact island where each of his birds originated.

Darwin had by then finished reading the next volume of
Principles of Geology
, which Henslow had sent to him in Uruguay. Lyell was a lawyer by trade, and in his second volume he turned his formidable skills at argument and logic to tearing down the transmutational assertions of Jean-Baptiste Lamarck. Lyell saw in the geology of the Earth a great transformational force, yet he saw no such force when it came to the plants and animals that inhabited it. Lamarck looked at the fossil record as proof that species had changed over time. Lyell contended that what Lamarck was really seeing was evidence of extinctions, followed by acts of creation, where God brought new, more able species into being. These new creations explained what seemed to be rather abrupt changes in the fossil record. There were no natural links between species dying out and new species appearing. The appearance of each new species was a miracle.

In the Galápagos, Darwin began to part ways, ever so cautiously, with Lyell's opinions about transmutation. In the mockingbirds of the islands, he began to see evidence of a gradual transformation of species, shaped by the demands of the changing environment that Lyell assumed. But he wasn't yet quite sure. The birds had differences, but in Darwin's view they were still merely variants of the same species. He noted his confusion in his ornithological journal. If these birds indeed turned out to be not simply variants, but distinct species, “such facts would undermine the stability of Species.” Their close proximity on each of the islands and their apparent strong similarity could not be mere chance, but evidence that the birds shared a common ancestor, from which they had evolved. Darwin was beginning to see Lyell's processes of change at work on not just Earth's geology, but life itself. In
the Galápagos, he would write, “We seem to be brought somewhat near to that great fact—that mystery of mysteries—the first appearance of new beings on earth.” Nineteen years would pass before he explained what he meant by that sentence.

F
ROM THE GALÁPAGOS
, the
Beagle
spent the final year of its journey sailing across the Pacific and around the horn of Africa, arriving in England in October of 1836, at the port of Falmouth. A steady stream of accounts of the expedition appeared in newspapers, and Darwin returned to find that his reputation had bloomed while he was away. For five years, he had maintained a correspondence with Henslow, and his geological observations so impressed his former professor that Henslow had gathered them into a pamphlet that he shared with other naturalists. Lyell was one of those who received a copy. He couldn't wait to meet the young man who described himself as Lyell's “disciple.”

Within a month of Darwin's return, the two dined at Lyell's London home. They got on famously from the very beginning, forming a friendship that would last their lifetimes. Lyell listened in rapt fascination as Darwin regaled him with stories of earthquakes in foreign lands. Lyell offered to shepherd the young man in his new career. He also advised Darwin to stay in London, where Darwin would be close to the array of specialists whose help he would need in deciphering all that he had seen and learned. Lyell invited one of the specialists he had in mind to dinner that evening, a young anatomist named Richard Owen, who would four years later coin the term “Dinosauria,” or “terrible reptiles.” Before Darwin left that night, Lyell, the head of the Geological Society of England, offered him one last piece of advice that seemed premature: waste no time heading a scientific organization. He was already certain that Darwin would go far.

Lyell and Darwin became nearly inseparable. For a spell, it seemed as if they met every day. Lyell helped guide his new protégé as best he could. Memberships in the most esteemed scientific organizations started piling up, including the Royal Society, the Royal Geographical Society, and, of
course, Lyell's Geological Society. Darwin also received a royal grant to help him write an account of his adventure and his observations that would be published as part of a multivolume memoir that FitzRoy had planned.

Darwin began putting his fieldwork data in order. To catalog the fossils he had found in Patagonia, he enlisted Richard Owen's help. Boxes of Darwin's fossils began arriving at the Royal College of Surgeons, which Owen headed. Darwin could still only guess as to what exactly the odd collection of interesting-looking bones would eventually yield. Owens soon informed Darwin that his collection contained pieces of a giant llama and the head of gigantic rodent that would have been about the size of a hippopotamus. Lyell gloriously paraded his protégé's finds before the Geological Society in an exhibit he called “Darwin's Menagerie.” For Lyell, these fossilized bones were evidence of a fascinating “law of succession,” in which God arranged his creations on the planet Earth in a kind of geographic order. Though similar in shape and structure, each was still unique, and unrelated by ancestry.

Darwin, however, was already beginning to suspect that all of his animal specimens were merely branches of a single family tree, each related by blood and genealogical history. These were still just speculations, but his instincts told him the giant llama had to be a cousin at least of the llamas that still lived on the South American continent. There had to be some connection, and an explanation that could be found in the decipherable laws of nature. It was not enough to simply see these variations as the work of divine creation. Owen, for his part, was a committed vitalist who believed that all living things contained an inherent “organizing energy” that governed bodily processes like growth and decay. Conservative and religious, he was, like Lyell, an ardent opponent of evolutionary concepts. Both would eventually change their minds. Owen would swing so far in the other direction as to one day attack Darwin for not embracing the implications that his evolutionary theory held for the origin of life.

I
N MAY OF 1838,
FitzRoy's four-volume account of the expedition was published under the title
Narrative of the Surveying Voyages of His Majesty's
Ships Adventure and Beagle
. The first two volumes consisted of FitzRoy's memoirs of the
Beagle
's expeditions, including the ship's first voyage under the command of Stokes. The last volume was a lengthy appendix. Darwin's account made up the third volume and quickly began to outstrip the others in popularity. It was soon published on its own as the
Journal of Researches into the Geology and Natural History of the Various Countries Visited by H.M.S. Beagle
. Later, it became, simply,
The Voyage of the Beagle
.

The description of the visit to the Galápagos filled only a small portion of Darwin's account, but it was the most historically significant. Of particular interest was a sentence about some birds he by then believed to be finches. “One might really fancy that from an original paucity of birds in this archipelago,” he wrote, “one species had been taken and modified for different ends.” It was a tantalizing—if cautious—glimpse of his increasing doubts about the notion of fixed species.

The animal specimens Darwin brought back took longer to decipher than his fossilized bones. In all, he brought back 80 stuffed mammals and 450 birds, which he entrusted to the Zoological Society of London. Despite having just added a new museum in the city's posh West End, the Zoological Society took them only reluctantly, and processing was slow. The society was turning into an organizational nightmare. It had put out a call for submissions for exhibitions but was unable to cope with a torrent of animal specimens that seemed to arrive daily from hunters and naturalists around the world, all of which needed to be tagged, described, and stored. Eventually, though, Darwin's specimens found their way into some of the surest hands the organization had, those of the taxidermist John Gould. A self-educated former gardener, Gould had pulled himself up through his skill at taxidermy, becoming the Zoological Society's first curator and preserver. He was also a fine painter who had authored and illustrated several popular books on birds.

The little birds Darwin had retrieved from the Galápagos were of particular interest to Gould, just as they were to Darwin. Gould concluded that these birds were actually thirteen distinct species of finches and three of mockingbirds, none of which existed outside their respective islands in the Galápagos. The differences in their beaks reflected the food sources
unique to each island: some were perfect for consuming various types of cactus seeds; others, for eating insects. Darwin finally had the answer he'd been waiting for, and he was confronted by evidence of evolution even more striking than that given by his fossils. Darwin was sure that each bird was related, that they all shared a common ancestor. At some point, a species of finch had made its way to the Galápagos and transformed itself into thirteen separate species. Only their beaks had adapted to the environment. But how? He stumbled upon a clue in the most unlikely place, an essay on political economy that had been suggested by a friend of his older brother Erasmus.

F
REETHINKING ABOLITIONIST
, portly poet, outgoing and generous, Erasmus Darwin was in many ways the mirror image of the grandfather for whom he had been named. Though he and his brother Charles differed little when it came to subjects like politics and religion, Erasmus was always the more daring. Like their grandfather, he was willing to strain the boundaries of respectability. Also like their grandfather—and their father—he was a physician, though he suffered from the same chronic bouts of illness that would one day haunt his brother. Their father, fearing that his son's medical career was too severe a strain on Erasmus's “body and mind,” advised his son to take early retirement. By the time Charles returned from the
Beagle
expedition, Erasmus had followed their father's suggestion and given up practicing medicine. He had not yet turned thirty.

But Erasmus remained active in society and in Whig political circles. Money was no impediment. Both he and Charles had at their disposal the large family fortune that stemmed from the industrial successes of their maternal grandfather, Josiah Wedgwood. Though Erasmus would eventually die a bachelor—and with an opium addiction—he was linked romantically to a number of freethinking women, including the radical political economist Harriet Martineau, who was mistakenly implicated as the mysterious author of
Vestiges of the Natural History of Creation
. The two began a long affair, and a lifelong friendship. The prospect of marriage to the outspoken, modern Martineau worried Erasmus's father, who asked Charles
to keep an eye on his brother. Over the coming years, Charles became, if not her friend, a close acquaintance.

Harriet Martineau was one of the most prominent intellectual disciples of the Reverend Thomas Malthus. A former economist for the British East India Company, Malthus had argued that increasing population growth would inevitably lead to increasing poverty, as the labor surplus would lead to a massive reduction in wages. The weak and the poor would be weeded out in the struggle for survival that was the natural state of human society. Starvation, disease, war, and even infanticide were, in Malthus's vision, natural checks on this delicate economic balance. His ideas earned him a place as the most influential economist of his time and spawned a reform movement that eventually led to a strengthening of the English “Poor Laws,” which established a system of workhouses for the most indigent.

Malthus's seminal book was
An Essay on the Principle of Population
. After a number of conversations with Martineau about Malthus, Darwin got around to reading the book in late 1838. Almost immediately, he had an epiphany. The struggle that Malthus identified in human society was the same as the struggle for survival that Darwin observed in nature. Darwin would later write in his autobiography, it “at once struck me that under these circumstances favourable variations would tend to be preserved and unfavourable ones to be destroyed. The result of this would be a new species. Here then I had at last got hold of a theory by which to work.” In his private notebooks, Darwin began reexamining the earlier theories of transmutation that had enraptured his grandfather. By applying Malthusian principles to the natural world, he finally grasped the basic mechanism of transmutation that had eluded his predecessors in the world of evolutionary theory. The variations in living creatures were the product of natural selection.

I
N CHARLES DARWIN'S TIME,
most people—including most scientists—saw life as something that had changed little since the era of biblical creation. Joseph Priestley, himself no orthodox follower of scripture, summed up the conventional view when, in a book about spontaneous generation, he
wrote that the “plants and animals described in the book of Job are the same as they are now, and so are the dogs, asses and the lions of Homer. The world is, no doubt, in a state of improvement, but notwithstanding this, we see no change in the vegetables and animals of other species.”