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Olivia Judson

WHY READ ON THE ORIGIN OF SPECIES BY CHARLES DARWIN? After all, it was first published more than 150 years ago, and much of the science is out of date. When Darwin was writing, for example, the rules of genetic inheritance had not been figured out, the causes of genetic variation were unknown, and the discovery of the structure of DNA – the molecule that contains genetic information – was almost 100 years in the future. In Darwin’s time no one knew how old the earth was, nor that the continents move across its surface. Viruses had not been discovered. In short, the landscape of scientific knowledge was far less filled in.

Nevertheless, there are excellent reasons to read it anyway.

Here’s one: It is among the most important books ever written. Publication of the Origin transformed biology and transformed our understanding of ourselves. Before the Origin, biology was essentially descriptive, an accumulation of unconnected facts and details called “natural history.” The patterns in nature were inexplicable. After the Origin, the patterns made sense, and the facts and details became part of a vast and sweeping picture. Before the Origin, we humans considered ourselves the pet creations of a deity. After the Origin, we became part of nature, related to every other being on the planet, with an ancestry that stretches back, back, back, across the eons, to the dawn of life.

It was a huge blow to human vanity. In showing that the earth orbits the sun, not the other way around, Copernicus had removed us from the center of the universe; then Darwin removed our special status as divine creations. Yet seen through the lens of evolution, our myriad imperfections – our capacities for violence and cruelty, our tendencies toward sexual infidelity, our irrationality – become comprehensible. Our finest attributes – our immense capacity for love, kindness, and self-sacrifice; our ability to cooperate; our consciousness; our languages; and our ability to articulate the world and study the universe – become more amazing. With the Origin we became one species among hundreds of millions – and the more astonishing for it.

Here’s a second reason to read the Origin: Darwin was a genius. Thus, as well as being a transformative text, the Origin is a window into the mind of one of the world’s greatest thinkers. To spend time with such a mind is an inspiration. The Origin is a book that, in my experience, becomes more profound on each reading. It is a book you can have a conversation with over a lifetime.

Yet Darwin was not a genius in the traditional mold. He was not obviously brilliant – at university he was an indifferent student – nor was he flamboyant. He did not write beautiful, elegant equations; nor did he wear peculiar costumes, gamble, cut off his ear, or engage in reckless love affairs. Indeed, having concluded that a wife would be “better than a dog,” he married his first cousin Emma Wedgwood shortly before his thirtieth birthday and remained with her until his death in 1882; they had ten children, of whom seven survived to adulthood. After his marriage, his life was outwardly dull, consisting of domestic stability, hard work, frequent illness, extensive correspondence, and regular walks. To be sure, there was drama, but it was mostly internal, as he began to realize that his discoveries would wrench human thought in new directions.

Instead of flamboyance and brilliance, Darwin’s genius lay in a mix of curiosity and courage, persistence and passion; it lay in great powers of observation and an attention to tiny details. This, after all, was a man who spent eight years writing the definitive study of barnacles, who made important discoveries about orchids, carnivorous plants, and earthworms, and who, as a young man, published a theory of the formation of coral reefs that is still considered correct. More than that – and this is where he is so exceptional – he took this vast accumulation of knowledge and put it all together into a grand new vision of the world. A vision that, in outline and grandeur, remains intact to this day. His work, moreover, can be understood by anyone who cares to try.

Charles Robert Darwin was born on 12 February 1809, the fifth child of a well-to-do family. At the age of sixteen he went to the University of Edinburgh to study medicine but did not stay the course, being horrified by the gory, screaming reality of surgery without anesthesia. When he quit, his father (himself a doctor) told him, “You care for nothing but shooting, dogs, and rat catching, and you will be a disgrace to yourself and all your family.” Plan B was to become a clergyman, and so Darwin was dispatched to study at the University of Cambridge. There, by a peculiar coincidence, he lived for a time in rooms that, more than sixty years earlier, had been occupied by William Paley – the natural theologian and moral philosopher who argued that the appearance of design in nature is evidence of a designer (i.e., God), just as a watch is evidence of a watchmaker, and whose writings were part of the curriculum. At Cambridge, Darwin collected beetles, shot birds, read the adventures of the great explorer Alexander von Humboldt, feasted with friends, and otherwise enjoyed himself prodigiously, in an aimless sort of way.

Then things changed. In 1831, when Darwin was twenty-two, he was invited to sail around the world on HMS Beagle in the position of companion to the captain – a post for which his family background as a gentleman was one of the chief qualifications. (His father disliked the idea, objecting that it was “a wild scheme” and would make him unfit for being a clergyman. Which it did – though not in the way his father was expecting.) The voyage lasted almost five years and took him to (among other places) Australia, South America, and the Galápagos Islands; it marked the beginning of his intellectual transformation. The Beagle returned to England in October 1836, and early in 1837, with all thoughts of becoming a clergyman having been abandoned, Darwin opened his first notebook on the “transmutation of species.” That is, on evolution.

Before the Origin, most naturalists believed that species were fixed entities created by a deity to fit their particular environments. Darwin himself started out with this belief. Doubt began to seep in while he was on board the Beagle, as he observed the living world firsthand and began to notice puzzling facts. If living beings have been specially created for their environments, why do the animals and plants that live on islands resemble those from the nearest mainland, where the environment is often quite different? Why is it possible for an animal “created” for Europe to thrive when introduced to Australia? Some geese almost never swim, yet they have webbed feet. Why? Many fish that live in the total darkness of caves are blind, yet they have the remnants of eyes. Why? Woodpeckers have many traits that make them good at climbing trees and ferreting insects out from under the bark, yet some woodpeckers with those traits eat only fruit, while others live on treeless plains. Why? Why? Why? Such questions perplexed Darwin and gradually led him to ponder evolution.

He was not the first to do so. Toward the end of the eighteenth century, Darwin’s grandfather, Erasmus Darwin, published speculations about evolution (in the fashion of the times, many of them were in poetical form). A few years later the great French biologist Jean-Baptiste Lamarck wrote the first major treatise arguing that evolution takes place. Like Darwin, Lamarck started out believing species were immutable and then changed his mind as a result of what he saw in nature. Darwin knew of Lamarck’s ideas: during his brief stint as a medical student, he became friends with the comparative anatomist Robert Grant, who spoke of Lamarck enthusiastically.

In 1844 Darwin wrote a long sketch of his own ideas about evolution. But fearing the ruckus it would cause, and feeling that he did not yet have enough evidence to be convincing, he did not make it public. Instead, he told a few friends about it, including the botanist Joseph Hooker, and wrote a letter to Emma, asking her, in the event of his death, to arrange to have it published. He then resumed work he was doing on other subjects.

Someone else was not so timid. Later the same year a Scottish writer, journalist, and publisher named Robert Chambers published – anonymously – a book called Vestiges of the Natural History of Creation, in which he put forward a mass of disconnected ideas about evolution, all completely speculative. The book was a sensation. Yet Chambers failed to persuade most people that evolution takes place. Indeed, none of these earlier writers and thinkers had the impact of the Origin.

One reason for this is obvious: they all lacked plausible mechanisms by which evolution could occur. Such as natural selection.

I will describe natural selection in a moment. But before I do, consider the fact that humans can, over time, produce huge changes in domestic animals. Just think of the different breeds of sheep, horse, and cow. Or think of the difference between a massive dog like a Great Dane and a tiny one like a Chihuahua. A single Great Dane can weigh more than twenty-five Chihuahuas. Such differences are caused by repeatedly selecting which individuals are allowed to breed with one another. To breed a big dog, then, you repeatedly select the biggest animals of each sex to breed with one another; to breed a little one, you do the reverse. This system works because size can be inherited – that is, it has a genetic component – and because different dogs have different genes. If the breeding is sustained for many generations, the resulting animals will be much larger (or smaller) than their ancestors.

Darwin saw that something similar happens in nature. But rather than humans selecting which traits are desirable, the selection happens as a natural consequence of the fact that different individuals have different genes.

To see what I mean, consider blue tits, small songbirds found throughout Europe and parts of Asia and North Africa. A typical pair has ten chicks in a brood, and some pairs have two broods a year – which is a lot of baby blue tits. So you might expect that the number of blue tits will grow rapidly from one year to the next.

But it does not. Bird census data shows that the number of blue tits does not increase dramatically. What happens to them all? They experience natural selection. That is, they get eaten by cats, or crows, or sparrow hawks – or they escape. They die of hunger, or cold, or disease – or they make it. They fail to find a place to nest, or, having found a nest, fail to attract a mate – or they have a successful mating season. Now, if one bird survives the cold because it is a little fatter or has warmer feathers, or if it escapes from the paw of the cat because it is a little flightier, or if one finds a mate because it is a little sexier, then the fatter, the featherier, the flightier, and the sexier individuals will be more likely to leave offspring. And if the reason for the fatness, featheriness, flightiness, or sexiness has a genetic component, then those traits will start to spread. Conversely, the thin, the unfeathery, the slow, and the unsexy will die – and their genes will be lost. Over time, if the same traits continue to be favored, the characteristics of the whole population will shift.

To put it more brutally, in all populations more individuals are born than can possibly survive and reproduce. Therefore, most individuals die prematurely. But individuals differ from one another in their inherited characteristics – that is, in their genes. If the difference between dying and surviving, between leaving no descendants and leaving some, is in part genetic, then the traits that enhance success – whatever they are – will start to spread, and those that hinder it will start to vanish. This is evolution by natural selection. The ingredients are genetic variation, the death of many coupled with the survival and reproduction of a few, and time.

Moreover, natural selection does not just shape obvious traits, such as how many flowers a plant produces or the number of legs possessed by a starfish. It can shape every aspect of living beings, from complex details of internal physiology to subtle aspects of behavior, as long as there is genetic variation for the traits in question.

Natural selection is the idea most closely associated with Darwin. Yet he was not the first to discover this either. For example, in 1831 – the same year that Darwin embarked on the Beagle – a Scottish journalist named Patrick Matthew published a clear and concise account of how natural selection works. Unfortunately for Matthew, however, he included it as an appendix to his book On Naval Timber and Arboriculture, and it went unnoticed. Darwin, for one, knew nothing about it until after the Origin was published, when Matthew wrote to a magazine to draw it to public attention. (In later years Matthew insisted on putting “Discoverer of the Principle of Natural Selection” on the title pages of his books. This irritated Darwin.)

But there was another discoverer of the principle of natural selection: Alfred Russel Wallace. In the history of biology the story is famous. In February 1858 Wallace wrote to Darwin from the island of Ternate, in what is now Indonesia, where he was collecting birds, beetles, butterflies, and anything else he could catch. The letter contained a manuscript in which Wallace had outlined the idea of evolution by natural selection (though he did not call it that; he referred instead to “a general principle in nature”). He asked Darwin, if he thought the manuscript sufficiently interesting, to forward it to the great geologist Sir Charles Lyell, who also happened to be a close friend and confidante of Darwin. Indeed, Darwin had already revealed his own ideas about evolution by natural selection to Lyell, and Lyell had already urged him to publish them.

On receiving Wallace’s letter, Darwin was devastated: he was about to be scooped. But as Wallace had asked, he sent the manuscript to Lyell, along with an anguished letter of his own. (“My dear Lyell . . . Your words have come true with a vengeance when you said I shd. [sic] be forestalled . . . all my originality, whatever it may amount to, will be smashed . . . I hope you will approve of Wallace’s sketch, that I may tell him what you say.”)

The upshot was that Lyell and Hooker arranged for Wallace’s paper, along with an excerpt from Darwin’s 1844 sketch and a letter that Darwin had previously written to the American botanist Asa Gray, to be read before a meeting of the Linnean Society in London on 1 July 1858. This ensured that both men received credit for the discovery of natural selection. Yet neither man was present at the meeting. Wallace was now in New Guinea, hunting birds of paradise, and Darwin was at home in Kent, mourning the death of his tenth child (from scarlet fever).

The meeting had little obvious impact. In May 1859 the president of the Linnean Society gave a report of the happenings of the previous twelve months. His verdict was that the year “has not, indeed, been marked by any of those striking discoveries which at once revolutionize, so to speak, the department of science on which they bear.” Looking back, this seems like one of the great misstatements of all time – but that’s because we know what happened next. Darwin, at last, had been galvanized to act. During the next weeks and months he wrote and wrote, drawing together materials, observations, and results amassed over more than twenty years; and late in November 1859, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life was published for the first time.

I have one of these first editions in front of me. The binding is green leather; the lettering on the spine is in gold. The volume is thick – just over five hundred pages. When I open it, it smells musty. Which makes me think for a moment of a chilly, misty November day in London – a jostling, Victorian, imperial London, a London of women in crinolines, men in top hats, and children sweeping manure from the streets. Turkey still had the Ottomans; Russia, the Tsars; convicts were still being transported to Australia. Slaves were picking cotton in the American South. Back then Germany did not exist as a country; nor did Italy, though it soon would. The composer Richard Wagner was writing Tristan und Isolde, his great opera of doomed love; Charles Dickens had recently published A Tale of Two Cities. Telephones, cars, airplanes – none existed, except in imagination.

And from that earlier world, comes the Origin.

The Origin is simultaneously an argument and a massive compilation of evidence, and it is this evidence that, more than anything else, is so persuasive and gave the book such impact. This is what sets the Origin apart from what was presented to the Linnean Society or from the writings of Patrick Matthew.

Darwin drew from every branch of biology then known – from fossils, animal embryos, human efforts at plant and animal breeding, the way animals and plants are distributed around the world, patterns of extinction, the presence of vestigial organs like the rudimentary eyes of cavefish, and so on – as well as from observations and numerous experiments, including many he conducted himself.

To see how his thinking unfolds, consider his treatment of islands. Darwin points out that the inhabitants of oceanic islands tend to be similar to – yet clearly different from – the inhabitants of the nearest continent. As an example, he gives the Galápagos Islands. These lie on the equator more than five hundred miles from the coast of South America, yet to a great extent the plants and land birds resemble those of the continent. So much so, says Darwin, that a naturalist feels he is “standing on American land.” To explain the resemblances, he proposes that the animals and plants on islands are not specially created for island life; rather, they arrive on the islands from the nearest mainland and begin to evolve in new directions. But if this is right, they need a way to travel across the ocean. Darwin points out that birds can do this easily – they can fly – but most land mammals cannot. Which explains why oceanic islands tend to have many unique species of bird, but (until humans sailed in with rats, pigs, goats, and other members of their entourage) no mammals except bats.

But what about plants? How do they travel? At the time, it was “known” that seeds could not survive being soaked in saltwater. But Darwin tested this. He set up jars of saltwater in his study and put seeds into them for various lengths of time; he then removed them, planted them, and investigated whether or not they sprouted. Sure enough, he discovered that many seeds can survive immersion, some for as long as 137 days. He then opened an atlas and, from the rate of the ocean currents, calculated that more than 10 percent of plants have seeds that could float more than nine hundred miles and still grow, should they happen to land in a favorable spot. And that’s not the only way plants can get around. They can also be carried by birds. Darwin observes that when birds eat fruit, the seeds often pass through the digestive system intact. A bird blown hundreds of miles off course in a gale could thus carry seeds to far-flung places. More astonishing is that birds that have eaten seeds may in turn be eaten by hawks or owls – and these twice-eaten seeds can still germinate. Similarly, if a fish eats a seed and is then eaten by a bird, the bird may become the agent of seed dispersal. This is not mere conjecture. Darwin forced seeds into the bellies of dead fish; fed the dead fish to fishing eagles, storks, and pelicans; and found that some hours later the seeds were either regurgitated or excreted, and that some of these seeds could still grow.

Again and again, Darwin takes an observation – in this case, the patterns of island life – and tests as many implications as he can think of. In doing so, he anticipates and defuses criticism after criticism.

He also makes a number of important and strikingly modern insights. For example, he realized that much of the time the greatest challenges in an organism’s environment come from other life forms – predators, parasites, competitors, potential mates, and so on – rather than aspects of the physical environment such as climate. It is, after all, the living environment that generates much of the intricacy in nature – the elaborate displays that have evolved to attract mates, or (in the case of plants) pollinators, the astonishing camouflage with which some animals blend into their surroundings, the various mechanisms by which organisms of all kinds fight off disease. Through evolving interactions, beings such as birds, moths, and flowers can shape each other in complex and beautiful ways.

Moreover, as Darwin recognized, these intricate relationships have broader implications. One is that nature is a web of relationships, and changes that affect life forms in one part of the web can have strong effects elsewhere. In one of his most famous passages he observes that red clover is pollinated only by bumblebees. But the number of bumblebees depends on the number of field mice, because field mice destroy bumblebee nests. The number of field mice is in turn affected by the number of cats, which means that sometimes cats will have a strong effect on the frequency of particular flowers.

A second implication is that evolution is local. So animals and plants living in Australia, or New Zealand, or Mauritius, or wherever, develop an evolving web of relationships among themselves. If an interloper that has evolved in a different web of relationships should happen to arrive, it will sometimes be able to flourish at the expense of the residents. For example, since oceanic islands typically lack ground-dwelling mammals, life forms there repeatedly evolve characteristics that they tend not to evolve if ground-dwelling mammals are present, such as birds losing the power of flight and evolving to nest on the ground. If rats, pigs, or humans should then arrive, these animals find themselves highly vulnerable to predation, or even extinction.

Darwin also realized that although behaviors and mental capacities seem somehow different from traits such as the color of a feather or the scent of a flower, they are not. This means that behaviors can evolve in the same way as any other trait. So if individuals vary in a behavior, and if that variation has some genetic basis, then the behavior can evolve through natural selection.

Over time, then, simple behaviors can potentially evolve into far more elaborate forms. To show how this could happen, Darwin takes the hexagonal combs built by honeybees and asks how the impulse to build such complex structures could have evolved through the slow accumulation of small but useful variations. This passage is one of the finest in the book; he sets up the full difficulty of the problem to be solved and then solves it with great elegance. The problem? Honeybees have evolved to build a complex comb that holds the maximum amount of honey while using the least amount of wax. To solve it, Darwin marshals evidence from other bees that build less complex combs, he writes to a mathematician to investigate the geometry of honeycombs, and he performs experiments to elucidate how honeybees actually build their combs. He concludes that the steps to making complex combs can be reduced to a few simple rules of thumb – and that the ability to follow these rules of thumb can readily evolve if the pressure to economize the use of wax is strong. If, that is, colonies that build more efficient combs tend to perpetuate themselves better than colonies whose combs are less efficient.

But the full magnificence of the Origin is this: it presents a worldview of extraordinary power, one that can explain the entire diversity of life on earth. The spiders, wombats, and algae; the earthworms, stag beetles, and luminous fungi; the tigers, oak trees, and all the rest; all the millions of different beings that are here on earth today as well as the countless billions that have lived here before are all bound together into a single tree of life, sculpted by forces of nature that we can identify and understand.

This worldview has several elements: through the tree of life, it gives kinship to all life forms; it predicts that every bacterium, beetle, or breadfruit tree can trace its ancestry back to the origin of life. In principle, then, it’s possible to draw a giant family tree, one that includes every being on the planet. But why are there so many different kinds of beings? This is due to what Darwin called “descent with modification,” meaning that over time, different populations evolve in different directions. This is, in part, because different populations experience natural selection in different ways: climates can be subtly different, local predators may be different, ditto the food, and so on. It is also, in part, because of what Darwin called “sexual selection,” which is the idea that by choosing who to mate with, males and females exert selection upon one another’s appearances, songs, scents, and other characteristics. Like natural selection, sexual selection can cause different populations to evolve in different directions. What’s more, sexual selection can interact with natural selection. A particularly good example of this interaction comes from recent research on guppies, small fish that live in streams. Female guppies prefer to mate with colorful males. Unfortunately, however, predators often find those males easier to see, so brighter males tend to get killed at a higher rate. Thus, in streams with large numbers of predators, males tend to evolve to be less flamboyant, whereas fewer predators leads to the evolution of more colorful males. Over time – especially immensely long periods of time, such as tens of millions of years – these various processes can produce spectacularly different outcomes in different places.

But there is something else to bear in mind. The substrate for all evolutionary change is genetic variation, which is ultimately caused by mutations to the information contained in DNA. If there is no variation for a trait, then that trait cannot evolve, even if evolution would be advantageous. For example, in one recent experiment, E. coli bacteria were grown in an environment that had a limited supply of glucose – the sugar they usually consume – but an abundance of citrate, which they usually cannot consume. It took more than thirty-one thousand generations for a citrate-consuming variant to appear. The reason is that evolving to consume citrate was not a matter of a single mutation, but of several. Still, even for bacteria that go through several generations every day, thirty-one thousand generations is a long time to wait. It also shows that evolution includes a sizeable dollop of chance – in this case, the chance that the necessary genetic variation will appear.

The tree of life, genetic variation, natural selection, sexual selection, chance, and time; these elements are all present in the Origin, and the view of evolution it presents is complete in outline. Yet the Origin is just that: the beginning of a new way of looking at life on earth, the first word on the subject, not the last. In the decades since 1859, Darwin’s ideas have been greatly developed and refined. Darwin himself led the charge; he published five further editions of the Origin in his lifetime, often revising heavily from one to the next. Some of the changes are corrections; others, responses to critics; still others incorporate new discoveries. By the sixth edition, which appeared in 1872, the text had grown to include a sketch of evolutionary thinking before the Origin, a glossary of terms, and an extra chapter.

But the big breakthroughs came a few decades later, starting with discoveries in genetics. Over the past century, an improved understanding of genetics has generated a far more robust framework for understanding how evolution works. Recent fossil discoveries, as well as better technologies for dating rocks, have vastly improved our understanding of the history of life. This is not surprising; on the contrary, it would be odd if someone writing more than 150 years ago had understood everything and entirely anticipated modern biology.

When Daniel Duzdevich first mentioned to me that he was putting On the Origin of Species into modern English, my first reaction was Really? Do you think it needs it? Chaucer, sure. But Darwin? Is he really that incomprehensible? On rereading and reflection, I concluded that the answer is often, yes.

To be sure, parts of the Origin are brilliant – lucid, clear, fascinating. Darwin is excellent at description; his best writing is when he is reporting the results of his experiments, or writing about subjects he understands well, such as the fossil record. He is sometimes eloquent, even passionate; the final chapter, where he brings all of his powers of persuasion to bear, is a triumph of rousing advocacy. But in other places he is plodding and opaque; the chapter on hybridism, for example, can defeat the most eager biologist.

He is, unsurprisingly, at his worst when writing about technical subjects he does not understand well or lacks the vocabulary to discuss. The obvious example is genetics; here, his writing is especially tortured and hard to follow. But it is easy to see why. He was writing about a subject that had not been developed yet – the word “gene” was not coined until early in the twentieth century – and his grasp of how traits are inherited was foggy. This fog shrouds his prose on the subject. It’s a pity he starts the book with genetics; many readers have surely been discouraged because the opening pages are so turgid.

But perhaps the chief reason that Darwin’s prose is difficult is that it is a kind of high Victorian writing. His sentences are often long, astonishingly convoluted, and sometimes digressive. From a modern standpoint, they also have peculiar punctuation. Add to that some archaic turns of phrase, and it’s easy to struggle.

Duzdevich is not the first to try to address these problems. In his book Almost Like a Whale (that was the original British title; in the United States the book was published as Darwin’s Ghost), geneticist Steve Jones imagined the text Darwin might have produced if he were writing now, with a modern knowledge of biology. Jones kept the same chapter structure and included some of Darwin’s original text in facsimile, but the book is nonetheless a radical reinvention of the original. James Costa, an evolutionary biologist, took a more orthodox approach and produced an annotated Origin, but while the annotations greatly help the reader to understand the background to Darwin’s thinking, they do not make the text any easier. Still another approach has been taken by Mark Ridley, also an evolutionary biologist, with an excellent short book called How to Read Darwin. Here, Ridley aims to inspire the reader to persevere. One of his suggestions: don’t start at the turgid beginning, but start at chapter 3. And be prepared to make an effort; when Darwin appears to be going on at great length about a subject that seems boring or irrelevant, stop and try to work out why he might be doing so. After all, he was writing for a different audience – an audience with different preconceptions from those we have now. In other words, says Ridley, this is not a book for reading passively, but for tackling and interrogating with gusto.

Such gusto is made much easier by Duzdevich’s rendition. For there is no doubt about it: Duzdevich’s Darwin is much easier to read than Darwin’s Darwin. Indeed, it was this realization that made me enthusiastic about the project and led me to conclude that it’s an important contribution, making this fundamental text far more accessible.

So what has Duzdevich done? He has not abridged the text, nor been so crude as to go through it striking out apparently extraneous words. Instead, he has taken the first edition of the Origin – which, as the first presentation of a world revolution in human thought, is of the greatest historical interest – and unfolded the sentences and made the syntax and punctuation more modern. He has also replaced some of the more archaic turns of phrase with modern terms. The insights and meaning are all there; the convolution is gone. In other words, he has made a careful translation of the text from Victorian English into twenty-first-century English. The upshot is that the text is much easier to grasp, appreciate, and think about.

Every time I open the Origin, I learn something new, and discover further reasons to be impressed by Darwin’s breadth of knowledge and depth of understanding. But more than that, the Origin and the worldview it contains have transformed the way I think about the planet, the beings on it, and what it means to be human. I find it a source of awe and optimism, reverence and consolation. I hope that, abetted by this new rendition, it will inspire the same feelings in you.

NOTES

I have drawn the details of Darwin’s life from Janet Browne’s excellent two-volume biography. Volume 1 is called Charles Darwin: Voyaging, published by Knopf in 1995. Volume 2 is called Charles Darwin: The Power of Place, published by Knopf in 2002. Any reference to the Origin is to the first edition.

For Darwin deciding that a wife would be “better than a dog,” as well as some other points in favor of marriage, see Voyaging, page 379. For his marrying Emma Wedgwood, see Voyaging, pages 391–401. For his fleeing the sight of surgery, see Voyaging, pages 62–63. For his father’s gloomy prediction about Darwin’s future, see Voyaging, page 89. For Darwin occupying Paley’s rooms at Cambridge and for Paley being on the syllabus, see Voyaging, page 93. For his lifestyle at Cambridge and his indifference toward his studies, see Voyaging, chapters 4 and 5. For details of the offer to travel on the Beagle (including a full list of his father’s objections to it), see Voyaging, chapter 6.

I have drawn Darwin’s “puzzling facts” from the pages of the Origin.

For Darwin being friends with Robert Grant, and for their discussing Lamarck together, see Voyaging, pages 80–83. For Darwin’s species sketch of 1844 and some of the reasons he did not want to publish it, see Voyaging, pages 445–47. For the impact of Vestiges, see Voyaging, pages 457–65.

Comparison of the relative weights of Great Danes and Chihuahuas assumes that a Great Dane weighs 174 lbs (78.9 kg) and a Chihuahua, 3 lbs (1.4 kg). For the lives of blue tits, see pages 225–48 of S. Cramp and C. M. Perrins, eds., 1993, Handbook of the Birds of Europe and the Middle East: The Birds of the Western Palearctic, Volume 7: Flycatchers to Shrikes (Oxford: Oxford University Press). For the parts of the world where you can find them, see page 227; for the number of chicks in a brood, see page 243, column 1. For annual mortality, see page 228.

Patrick Matthew’s sketch of natural selection, which appears as the appendix to On Naval Timber and Arboriculture, is well worth reading; the text is available free online from Google Books. For Darwin’s irritation with Matthew, see The Power of Place, page 109. For Wallace’s letter and Darwin’s reaction to it, see The Power of Place, pages 14–17; for Wallace formulating natural selection, see The Power of Place, pages 31–33. For details of how the presentation to the Linnean Society came about (and Darwin’s absence from it), see The Power of Place, pages 33–39; for the meeting itself, see The Power of Place, pages 40–41; for the great misstatement by the president of the society, see The Power of Place, page 42. All the material presented to the Linnean Society on 1 July 1858 is available at http://wallace-online.org/content/record?itemID=S043.

For Darwin’s account of life on oceanic islands, see the Origin, chapter 12. For his experiments on seeds, and for his feeding fish stuffed with seeds to birds, see the Origin, chapter 11. His description of bumblebees, clover, and cats comes from the Origin, chapter 3. His description of honeybees and their combs comes from the Origin, chapter 7. For sexual selection and natural selection in guppies, see J. A. Endler, 1980, “Natural Selection on Color Patterns in Poecilia reticulata,” Evolution 34: 76–91. For the experiment on E. coli, see Z. D. Blount, C. Z. Borland, and R. E. Lenski, 2008, “Historical Contingency and the Evolution of a Key Innovation in an Experimental Population of Escherichia coli,” Proceedings of the National Academy of Sciences USA 105: 7899–7906.

For a full account of the scale of changes between the editions of the Origin published in Darwin’s lifetime, see the introduction to M. Peckham, The Origin of Species by Charles Darwin: A Variorum Text (Philadelphia: University of Pennsylvania Press, 1959).

Many thanks to Jerry Coyne, Daniel Duzdevich, Dan Haydon, Gideon Lichfield, Richard Nash, Jean-Olivier Richard, Jonathan Swire, and especially, Ben Mason for insights, comments, and suggestions.