About the Author

Also by Charles Darwin

Title Page


Note on the Text




Index to The Voyage of the Beagle

Index to The Origin of Species







Causes of Variability – Effects of Habit – Correlation of Growth – Inheritance – Character of Domestic Varieties – Difficulty of distinguishing between Varieties and Species – Origin of Domestic Varieties from one or more Species – Domestic Pigeons, their Differences and Origin – Principle of Selection anciently followed, its Effects – Methodical and Unconscious Selection – Unknown Origin of our Domestic Productions – Circumstances favourable to Man’s power of Selection


Variability – Individual differences – Doubtful species – Wide ranging, much diffused, and common species vary most – Species of the larger genera in any country vary more than the species of the smaller genera – Many of the species of the larger genera resemble varieties in being very closely, but unequally, related to each other, and in having restricted ranges


Bears on natural selection – The term used in a wide sense – Geometrical powers of increase – Rapid increase of naturalized animals and plants – Nature of the checks to increase – Competition universal – Effects of climate – Protection from the number of individuals – Complex relations of all animals and plants throughout nature – Struggle for life most severe between individuals and varieties of the same species; often severe between species of the same genus – The relation of organism to organism the most important of all relations


Natural Selection–its power compared with man’s selection–its power on characters of trifling importance – its power at all ages and on both sexes – Sexual Selection – On the generality of intercrosses between individuals of the same species – Circumstances favourable and unfavourable to Natural Selection, namely, intercrossing, isolation, number of individuals – Slow action – Extinction caused by Natural Selection – Divergence of Character, related to the diversity of inhabitants of any small area, and to naturalization–Action of Natural Selection, through Divergence of Character and Extinction, on the descendants from a common parent – Explains the Grouping of all organic beings


Effects of external conditions – Use and disuse, combined with natural selection; organs of flight and of vision – Acclimatization – Correlation of growth – Compensation and economy of growth – False correlations – Multiple, rudimentary, and lowly organized structures variable – Parts developed in an unusual manner are highly variable: specific characters more variable than generic: secondary sexual characters variable – Species of the same genus vary in an analogous manner – Reversions to long-lost characters – Summary


Difficulties on the theory of descent with modification – Transitions – Absence or rarity of transitional varieties – Transitions in habits of life – Diversified habits in the same species – Species with habits widely different from those of their allies – Organs of extreme perfection – Means of transition – Cases of difficulty – Natura non facit saltum – Organs of small importance – Organs not in all cases absolutely perfect – The law of Unity of Type and of the Conditions of Existence embraced by the theory of Natural Selection


Instincts comparable with habits, but different in their origin – Instincts graduated – Aphides and ants – Instincts variable – Domestic instincts, their origin – Natural instincts of the cuckoo, ostrich, and parasitic bees – Slave-making ants – Hive-bee, its cell-making instinct – Difficulties on the theory of the Natural Selection of instincts – Neuter or sterile insects – Summary


Distinction between sterility of first crosses and of hybrids – Sterility various in degree, not universal, affected by close interbreeding, removed by domestication – Laws governing the sterility of hybrids – Sterility not a special endowment, but incidental on other differences – Causes of the sterility of first crosses and of hybrids – Parallelism between the effects of changed conditions of life and crossing – Fertility of varieties when crossed and of their mongrel offspring not universal – Hybrids and mongrels compared independently of their fertility – Summary


On the absence of intermediate varieties at the present day – On the nature of extinct intermediate varieties; on their number – On the last vast lapse of time, as inferred from the rate of deposition and of denudation – On the poorness of our palaeontological collections – On the intermittence of geological formations – On the absence of intermediate varieties in any one formation – On the sudden appearance of groups of species – On their sudden appearance in the lowest known fossiliferous strata


On the slow and successive appearance of new species – On their different rates of change – Species once lost do not reappear – Groups of species follow the same general rules in their appearance and disappearance as do single species – On Extinction – On simultaneous changes in the forms of life throughout the world – On the affinities of extinct species to each other and to living species – On the state of development of ancient forms – On the succession of the same types within the same areas – Summary of preceding and present chapters


Present distribution cannot be accounted for by differences in physical conditions – Importance of barriers – Affinity of the productions of the same continent – Centres of creation – Means of dispersal, by changes of climate and of the level of the land, and by occasional means – Dispersal during the Glacial period co-extensive with the world


Distribution of fresh-water productions – On the inhabitants of oceanic islands – Absence of Batrachians and of terrestrial Mammals – On the relation of the inhabitants of islands to those of the nearest mainland – On colonization from the nearest source with subsequent modification – Summary of the last and present chapters


CLASSIFICATION, groups subordinate to groups – Natural system – Rules and difficulties in classification, explained on the theory of descent with modification – Classification of varieties – Descent always used in classification – Analogical or adaptive characters – Affinities, general, complex and radiating – Extinction separates and defines groups – MORPHOLOGY, between members of the same class, between parts of the same individual – EMBRYOLOGY, laws of, explained by variations not supervening at an early age, and being inherited at a corresponding age – RUDIMENTARY ORGANS; their origin explained – Summary


Recapitulation of the difficulties on the theory of Natural Selection – Recapitulation of the general and special circumstances in its favour – Causes of the general belief in the immutability of species – How far the theory of natural selection may be extended – Effects of its adoption on the study of Natural history – Concluding remarks





Porto Praya – Ribeira Grande – Atmospheric Dust with Infusoria – Habits of a Sea-slug and Cuttle-fish – St. Paul’s Rocks, non-volcanic – Singular Incrustations – Insects the first Colonists of Islands – Fernando Noronha – Bahia – Burnished Rocks – Habits of a Diodon – Pelagic Confervæ and Infusoria – Causes of discoloured Sea


Rio de Janeiro – Excursion north of Cape Frio – Great Evaporation – Slavery – Botofogo Bay – Terrestrial Planariæ – Clouds on the Corcovado – Heavy Rain – Musical Frogs – Phosphorescent Insects – Elater, springing powers of – Blue Haze – Noise made by a Butterfly – Entomology – Ants – Wasp killing a Spider – Parasitical Spider – Artifices of an Epeira – Gregarious Spider – Spider with an unsymmetrical Web


Monte Video – Maldonado – Excursion to R. Polanco – Lazo and Bolas – Partridges – Absence of Trees – Deer – Capybara, or River Hog – Tucutuco – Molothrus, cuckoo-like habits – Tyrant-flycatcher – Mocking-bird – Carrion Hawks – Tubes formed by Lightning – House struck


Rio Negro – Estancias attacked by the Indians – Salt Lakes – Flamingoes – R. Negro to R. Colorado – Sacred Tree – Patagonian Hare – Indian Families – General Rosas – Proceed to Bahia Blanca – Sand Dunes – Negro Lieutenant – Bahia Blanca – Saline Incrustations – Punta Alta – Zorillo


Bahia Blanca – Geology – Numerous gigantic extinct Quadrupeds – Recent Extinction – Longevity of Species – Large Animals do not require a luxuriant Vegetation – Southern Africa – Siberian Fossils – Two Species of Ostrich – Habits of Oven-bird – Armadilloes – Venomous Snake, Toad, Lizard – Hybernation of Animals – Habits of Sea-Pen – Indian Wars and Massacres – Arrow-head, antiquarian Relic


Set out for Buenos Ayres – Rio Sauce – Sierra Ventana – Third Posta – Driving Horses – Bolas – Partridges and Foxes – Features of the Country – Long-legged Plover – Teru-tero – Hail-storm – Natural Enclosures in the Sierra Tapalguen – Flesh of Puma – Meat Diet – Guardia del Monte – Effects of Cattle on the Vegetation – Cardoon – Buenos Ayres – Corral where Cattle are slaughtered


Excursion to St. Fé – Thistle-Beds – Habits of the Bizcacha – Little Owl – Saline Streams – Level Plains – Mastodon – St. Fé – Change in Landscape – Geology – Tooth of extinct Horse – Relation of the Fossil and recent Quadrupeds of North and South America – Effects of a great Drought – Parana – Habits of the Jaguar – Scissor-beak – Kingfisher, Parrot, and Scissor-tail – Revolution – Buenos Ayres – State of Government


Excursion to Colonia del Sacramiento – Value of an Estancia – Cattle, how counted – Singular Breed of Oxen – Perforated Pebbles – Shepherd-dogs – Horses Broken-in, Gauchos Riding – Character of Inhabitants – Rio Plata – Flocks of Butterflies – Aëronaut Spiders – Phosphorescence of the Sea – Port Desire – Guanaco – Port St. Julian – Geology of Patagonia – Fossil gigantic Animal – Types of Organization constant – Change in the Zoology of America – Causes of Extinction


Santa Cruz – Expedition up the River – Indians – Immense Streams of Basaltic Lava – Fragments not transported by the River – Excavation of the Valley – Condor, habits of – Cordillera – Erratic Boulders of great size – Indian Relics – Return to the Ship – Falkland Islands – Wild Horses, Cattle, Rabbits – Wolf-like Fox – Fire made of Bones – Manner of hunting Wild Cattle – Geology – Streams of Stones – Scenes of Violence – Penguin – Geese – Eggs of Doris – Compound Animals


Tierra del Fuego, first arrival – Good Success Bay – An Account of the Fuegians on board – Interview with the Savages – Scenery of the Forests – Cape Horn – Wigwam Cove – Miserable Condition of the Savages – Famines – Cannibals – Matricide – Religious Feelings – Great Gale – Beagle Channel – Ponsonby Sound – Build Wigwams and settle the Fuegians – Bifurcation of the Beagle Channel – Glaciers – Return to the Ship – Second Visit in the Ship to the Settlement – Equality of Condition amongst the Natives


Strait of Magellan – Port Famine – Ascent of Mount Tarn – Forests – Edible Fungus – Zoology – Great Sea-weed – Leave Tierra del Fuego – Climate – Fruit-trees and Productions of the Southern Coasts – Height of Snow-line on the Cordillera – Descent of Glaciers to the Sea – Icebergs formed – Transportal of Boulders – Climate and Productions of the Antarctic Islands – Preservation of Frozen Carcasses – Recapitulation


Valparaiso – Excursion to the Foot of the Andes – Structure of the Land – Ascend the Bell of Quillota – Shattered Masses of Greenstone – Immense Valleys – Mines – State of Miners – Santiago – Hot-baths of Cauquenes – Goldmines – Grinding-mills – Perforated Stones – Habits of the Puma – El Turco and Tapacolo – Humming-birds


Chiloe – General Aspect – Boat Excursion – Native Indians – Castro – Tame Fox – Ascend San Pedro – Chonos Archipelago – Peninsula of Tres Montes – Granitic Range – Boat-wrecked Sailors – Low’s Harbour – Wild Potato – Formation of Peat – Myopotamus, Otter and Mice – Cheucau and Barking-bird – Opetiorhynchus – Singular Character of Ornithology – Petrels


San Carlos, Chiloe – Osorno in eruption, contemporaneously with Aconcagua and Coseguina – Ride to Cucao – Impenetrable Forests – Valdivia – Indians – Earthquake – Concepcion – Great Earthquake – Rocks fissured – Appearance of the former Towns – The Sea black and boiling – Direction of the Vibrations – Stones twisted round – Great Wave – Permanent elevation of the Land – Area of Volcanic Phenomena – The connexion between the elevatory and eruptive forces – Cause of Earthquakes – Slow elevation of Mountain-chains


Valparaiso – Portillo Pass – Sagacity of Mules – Mountain-torrents – Mines, how discovered – Proofs of the gradual Elevation of the Cordillera – Effect of Snow on Rocks – Geological Structure of the two Main Ranges, their distinct Origin and Upheaval – Great Subsidence – Red Snow – Winds – Pinnacles of Snow – Dry and clear Atmosphere – Electricity – Pampas – Zoology of the opposite sides of the Andes – Locusts – Great Bugs – Mendoza – Uspallata Pass – Silicified Trees buried as they grew – Incas Bridge – Badness of the Passes exaggerated – Cumbre – Casuchas – Valparaiso


Coast-road to Coquimbo – Great Loads carried by the Miners – Coquimbo – Earthquake – Step-formed Terraces – Absence of recent Deposits – Contemporaneousness of the Tertiary Formations – Excursion up the Valley – Road to Guasco – Deserts – Valley of Copiapó – Rain and Earthquakes – Hydrophobia – The Despoblado – Indian Ruins – Probable Change of Climate – River-bed arched by an Earthquake – Cold Gales of Wind – Noises from a Hill – Iquique – Salt Alluvium – Nitrate of Soda – Lima – Unhealthy Country – Ruins of Callao, overthrown by an Earthquake – Recent Subsidence – Elevated Shells on San Lorenzo, their decomposition – Plain with embedded Shells and fragments of Pottery – Antiquity of the Indian Race


The whole Group Volcanic – Number of Craters – Leafless Bushes – Colony at Charles Island – James Island – Salt-lake in Crater – Natural History of the Group – Ornithology, curious Finches – Reptiles – Great Tortoises, habits of – Marine Lizard, feeds on Sea-weed – Terrestrial Lizard, burrowing habits, herbivorous – Importance of Reptiles in the Archipelago – Fish, Shells, Insects – Botany – American type of organization – Differences in the Species or Races on different Islands – Tameness of the Birds – Fear of Man, an acquired instinct


Pass through the Low Archipelago – Tahiti – Aspect – Vegetation on the Mountains – View of Eimeo – Excursion into the Interior – Profound Ravines – Succession of Waterfalls – Number of wild useful Plants – Temperance of the Inhabitants – Their moral state – Parliament convened – New Zealand – Bay of Islands – Hippahs – Excursion to Waimate – Missionary Establishment – English Weeds now run wild – Waiomio – Funeral of a New Zealand Woman – Sail for Australia


Sydney – Excursion to Bathurst – Aspect of the Woods – Party of Natives – Gradual Extinction of the Aborigines – Infection generated by associated men in health – Blue Mountains – View of the grand gulf-like Valleys – Their Origin and Formation – Bathurst, general civility of the lower orders – State of Society – Van Diemen’s Land – Hobart Town – Aborigines all banished – Mount Wellington – King George’s Sound – Cheerless aspect of the Country – Bald Head, calcareous Casts of Branches of Trees – Party of Natives – Leave Australia


Keeling Island – Singular appearance – Scanty Flora – Transport of Seeds – Birds and Insects – Ebbing and flowing Springs – Fields of dead Coral – Stones transported in the Roots of Trees – Great Crab – Stinging Corals – Coral-eating Fish – Coral Formations – Lagoon Islands, or Atolls – Depth at which reef-building Corals can live – Vast Areas interspersed with low Coral Islands – Subsidence of their Foundations – Barrier Reefs – Fringing Reefs – Conversion of Fringing Reefs into Barrier Reefs, and into Atolls – Evidence of Changes in Level – Breaches in Barrier Reefs – Maldiva Atolls; their peculiar structure – Dead and submerged Reefs – Areas of Subsidence and Elevation – Distribution of Volcanoes – Subsidence slow, and vast in amount


Mauritius, beautiful appearance of – Great crateriform Ring of Mountains – Hindoos – St. Helena – History of the Changes in the Vegetation – Cause of the Extinction of Land-shells – Ascension – Variation in the Imported Rats – Volcanic Bombs – Beds of Infusoria – Bahia – Brazil – Splendour of Tropical Scenery – Pernambuco – Singular Reef – Slavery – Return to England – Retrospect on our Voyage

About the Author

Charles Darwin was born on 12 February 1809 in Shrewsbury. He was educated at Edinburgh University and Christ’s College, Cambridge. Between 1831 and 1836 he travelled in South America aboard the H.M.S. Beagle to explore the geology and natural history of the area, and published his journal of the voyage in 1839. His most famous book, On the Origin of Species by Means of Natural Selection, appeared in 1859 and is arguably one of the most important scientific works ever published. The theories of evolution and natural selection proposed in this book and The Descent of Man (1871) are still the subject of intense debate and scrutiny today. Charles Darwin died on 19 April 1882 and was buried in Westminster Abbey.


The Zoology of the Voyage of H.M.S. Beagle

Geological Observations on South America

The Variation of Animals and Plants Under Domestication

The Descent of Man and Selection in Relation to Sex

The Expression of the Emotions in Man and Animals

Insectivorous Plants

The Effects of Cross and Self Fertilization in the Vegetable Kingdom

The Different Forms of Flowers on Plants of the Same Species

The Formation of Vegetable Mould through the Actions of Worms, with Observations on their Habits

The Autobiography of Charles Darwin (published posthumously)




Both The Voyage of the Beagle and The Origin of Species were written at speed and under pressure because Charles Darwin received a letter. One letter in 1831 when he was twenty-two, one in 1858 when he was forty-nine. One was a lovely surprise, the offer of a journey that would change his life. The other was a horrible shock which threatened his life’s work. Both books were instantly popular. In 1839 the first made him a well-known travel-cum-science writer in Britain. The other, in 1859, swept him to an international fame he found almost unbearable and changed how we think about life.

In summer 1831 Charles Darwin was a young man with an Arts degree, about to enter the Church. He had studied Classics at school, read Divinity at Cambridge, been brought up Unitarian, believed in God and planned to be a parson. Like his grandfather, the poet-doctor Erasmus Darwin, Charles’s father was an affluent doctor. Charles expected to live the life of an English gentleman pursuing natural history as a hobby, to which Bible and Church were the comfortable background. Science was not incompatible with religion. He had studied medicine for two years at Edinburgh University, where he fell in love with marine zoology, read a scientific paper on it, and went to natural history lectures. At Cambridge, he read Divinity but discussed natural history with the Botany Professor John Henslow – who was also the Reverend Henslow, curate of Little St. Mary’s church. After passing his exams, Charles joined Cambridge’s Geography Professor, Adam Sedgwick, on a geological tour of Wales. Now he was looking forward to a summer of flirting with Fanny Owen, who lived near his home in Shrewsbury. Afterwards, he would train for the Church, but he dreamed of mounting a natural history expedition to Tenerife. How long can you wear a shirt in the tropics, he wondered, without washing it?

Then came a letter from Professor Henslow. A gentleman naturalist was required to accompany a Captain Fitzroy on a two-year Admiralty survey of South America: to Tierra del Fuego and back via the West Indies, starting in two months – and Henslow had recommended him for the post!

His dream come true, Charles said he’d go. Then he found his father was against it. The trip would unfit him to be a clergyman and he had no experience of seafaring – but Charles’s uncle persuaded the Doctor to let him go. ‘I’d have to be deuced clever to get into debt on a boat,’ Charles said as they renegotiated. His father, very fond of Charles but so far disappointed in him, was rapidly revising his picture of his son. ‘They all say you are very clever,’ he replied. And he put up the funds for the journey.

The voyage began in December 1831, took five years not two, and Charles often longed to go home. The ceiling of the living quarters he shared with Fitzroy was five foot six inches high: six inches lower than Charles. He was constantly seasick and Fitzroy had a volatile temper. They quarrelled, but made it up – and Darwin anyway spent over half of the five years on land, making surveys and collecting mammal, bird, marine, fossil and geological specimens. When he returned in October 1836 there were no more thoughts of parsoning. (Nor of Fanny Owen: a few days after the Beagle sailed she accepted another man.) He plunged into studying and editing the physical results of the journey, those specimens, turning them into written results. Between 1839 and 1843 he published The Zoology of the Voyage of H.M.S. Beagle, Edited and superintended by Charles Darwin in nineteen numbers.

Meanwhile he discussed the bird, mammal, reptile, marine and fossil findings with experts, especially on taxonomy. He wrote the geology himself for this was how he now saw himself: as a geologist. He joined the Royal Geological Society and became its Secretary. The voyage had turned him into a scientist. ‘Everything I thought or read,’ he said later, ‘was made to bear directly on what I had seen or was likely to see. This habit of mind continued during the five years of my voyage. I feel sure that it was this training which has enabled me to do whatever I have done in science.’

But the voyage had made him a writer too. This is where the first of the classics in this volume comes in.

While waiting to embark in 1831, Darwin began a journal which he sent back in instalments for his family. ‘During some part of the day I wrote my journal,’ he explained long after in his memoir, ‘and took much pains in describing carefully and vividly all that I had seen; and this was good practice.’ While doing close scientific observation he was also teaching himself to write. In 1836 this training bore fruit. Fitzroy asked him to contribute a natural history section to his account of the Beagle’s voyage. Using his journal and field notes, Darwin wrote a text which eventually became The Voyage of the Beagle, Darwin’s first book.

He gave it to Fitzroy in September 1837, eleven months after landing. In May 1839 Fitzroy published it as the third in a four-volume work, Narrative of the Surveying Voyages of His Majesty’s Ships Adventure and Beagle. The first was the Beagle’s previous voyage, the second was Fitzroy’s account; the fourth was an appendix. But Darwin’s volume, a thrilling travel book with a infectiously personal tone that was also a scientific field journal of biology, geology and exciting anthropology, was so popular that the publisher reissued it alone, retitling it Journal of Researches into the Geology and Natural History of the various countries visited by H.M.S. Beagle. In 1844, Darwin revised it in the light of research on his specimens and his developing ideas.

In 1858, twenty-seven years after Henslow’s original letter of invitation, after writing numerous scientific papers and books on geology, fossils, zoology and botany, he received the second crucial letter of his life, which pushed him into writing the book popularly associated with his name now, the second classic in this volume: The Origin of Species.

To understand what happened, we have to think of the inner rather than outer results of that original voyage. What went on in this young man’s head, at the time and also afterwards, when he started to absorb what he had seen?

When Charles first climbed into his hammock in Portsmouth harbour, beside him lay the New Testament in Greek and Milton’s Paradise Lost.

Milton had been at the same Cambridge college as Darwin – Christ’s – two centuries before. Now the book Darwin would take with him everywhere was Milton’s epic on the Creation and the Fall. Of course. He had studied theology and he was about to see the vastness of the world created, so he believed when he went to sleep that first night, by God.

But he was also the Beagle’s geologist. Captain Fitzroy was keen on natural history and gave him the first volume of a book making huge ripples at the time: Charles Lyell’s Principles of Geology.

In the late eighteenth century, geology had been a disturbing science for Christianity because it questioned the timescale of the creation story in the Bible. In 1802 an answer to some of those worries turned up in William Paley’s Natural Theology: Evidence of the Attributes and Existence of the Deity collected from Appearances of Nature. The premise of ‘natural theology’ was that the very complexity of the world proved divine creation. You couldn’t lift your hand to your head without being convinced of God’s existence. Think how many things are needed to perform that simple act! How could this happen without intelligence? In 1819, William Buckland, in an inaugural lecture at Oxford, argued that even geology had a role to play in ‘natural theology’.

Natural theology rested on an idea which was revived by beleaguered US creationists in the 1980s, nearly two hundred years after Paley, as ‘intelligent design’: that design implies a designer. To ‘prove’ this idea, Paley brought back an image which Descartes had used to explain God’s relationship to the structure of the universe. If you see a watch, you infer that someone made it. A watch implies a watch-maker.

In The Blind Watchmaker (1986), Richard Dawkins turned that image upside down by contrasting human making, design by intention, with the workings of natural selection in evolution which is a purely organic process, not driven by forward planning. Any maker, Dawkins argued, must be blind.

But in 1831 most geologists, including Lyell, believed in natural theology. What Lyell’s book made people question was not faith itself but a literal interpretation of Biblical Creation: that the world’s time was set going quite recently. Lyell’s principle was that the present is the key to the past. We explain geological remains by geological processes we still see in operation, which are caused by the steady accumulation of tiny changes over almost unthinkably long spans of time.

Fitzroy was impressed. When they explored sedimented rock formations in South America it was Fitzroy who said this ‘could never have been effected by a forty days’ flood’. After the Beagle voyage, however, Fitzroy married a devout Christian and changed his mind. In his account of the voyage he interpreted Genesis literally, renouncing Lyell, taking back his own remarks abut the Flood.

For Darwin, though, Lyell was a revelation and catalyst to new thought. The Beagle’s first stop was the Cape Verde islands. Seeing rock formation ‘through Lyell’s eyes’ gave him new insight into geologic history. During the voyage he got hold of Lyell’s second volume and started rethinking how the world came to be. ‘I always feel as if my books came half out of Lyell’s brain,’ he said long after.

New contemporary ideas about animals and plants also questioned conventional beliefs about time and change. Aristotle had said species never changed, which fitted the Bible’s account of Creation, but the possibility that species did change over time had been suggested three centuries before Aristotle and many people had supported it since, including Charles’s grandfather Erasmus Darwin whose Zoönomia (1794) offered views of ‘generation’ which anticipated Jean-Baptiste Lamarck.

Lamarck’s Philosophie zoologique (1809) set the tone for much subsequent thinking in evolutionary biology. No one said ‘evolution’ then: the word became common after the The Origin of Species, in 1859. Lamark’s word was ‘transmutation’, which stressed the core idea that one species mutated into another. Lamarck, arguing for ‘transmutation of species’, suggested that simple forms of life were created continuously by spontaneous generation. An innate ‘life force’ allowed species to become more complex over time, by making their organs adapt to their environment. The characteristics they acquired through change were inherited by the next generation.

The churchman William Paley was against this. Seventy years before Darwin, Paley had also attended Christ’s College. Darwin later even lived in his rooms. Paley’s book was required reading for Divinity. ‘I did not trouble myself then about Paley’s premises,’ Darwin said afterwards. ‘Taking these on trust, I was charmed and convinced by the long line of argumentation. I do not think I hardly ever admired a book more. I could almost formerly have said it by heart.’

Most geologists believed natural theology but rejected Lamarck. Lyell did not credit ‘scriptural geology’, but did reject any idea that species changed. He suggested creation was progressive: each species had its ‘centre of creation’, was designed by God for a particular habitat and became extinct when this habitat changed.

But Darwin’s Beagle notes of 1831–1836 show him following the process that became the hallmark of his mind ever after: noticing physical details closely and freshly, wondering about them and then, while writing them up, speculating anew about what they meant. In doing so he addressed the question of how to relate geological separation to the astonishing diversity of living (and fossil) species.

‘I could not help noticing,’ he wrote in 1832 after leaving Rio, ‘how exactly the animals and plants in each region are adapted to each other. Nature when she formed them, knew they must reside together.’ Early in 1833, on the Falkland Islands, he noticed the difference between the land’s desolation now and the seas which must, given the fossils in the oldest rock, have teemed with life there long ago. All this pointed to that contentious issue: continuous change, not only geological but organic. By June, he was relating the lack of dung-eating beetles in Maldonado to the dearth of dung-producing mammals, which seemed ‘a very beautiful fact, as showing a connection in the creating of animals as widely apart as Mammalia and Insects’. By 1836, he saw that the mockingbirds on the second Galapagos Island he visited were different from those on the first. Everything in his previous thought had led to this observation; everything in his subsequent thought stemmed from it. He wrote five pages on the ornithology of these Islands, ‘tenanted by the same birds slightly differing in structure and filling the same place in Nature’.

He hadn’t got to natural selection and evolution yet, but he was on the way.

‘I must suspect they are only varieties,’ he wrote. ‘If there is the slightest foundation for these remarks the zoology of Archipelagos will be well worth examining; for such facts would undermine the stability of Species.’

But he kept this possibility to himself.

The years after Darwin’s return, 1836–1839, were crucial to his thought. He made friends with Lyell. Publicly, he worked on the specimen results and wrote his book for Fitzroy. Privately, he began a series of notebooks which led to The Origin of Species (1859), The Descent of Man (1871) and On the Expressions of the Emotions in Man and Animals (1872)

In March 1837, his bird taxonomist John Gould told him about three types of Beagle birds. The rhea from the southern pampas was a different species from that in the northern pampas. In Galapagos, the finches were an entirely new group and all different; and the mockingbirds on different islands were different species.

Suddenly Darwin saw a vital parallel about the divergence of species over space and time. Geographical relationships between living species were like temporal relationships between living and extinct species. This led to his own version and explanation of ‘transmutation of species’. Everything, including human beings, was part of one ancestral chain. ‘Arrogantly’, Man believed he was ‘a great work, worthy a Deity’s glance’. Darwin felt it was ‘more humble and true’ to think of man ‘created, not bandbox new but slowly’ – from the animals. ‘Once you have granted one species may change to another,’ he wrote, mind racing, ‘the whole fabric totters and falls.’ He sketched a little diagram, half tree, half star-burst, showing how different species could evolve from a single ancestral species, branching off from each other.

His rough sketch of the ‘tree of life’ seems obvious today but reaching it was not easy. Faced with the huge diversity of species, everyone assumed God had created each separately, down to the smallest muddiest mollusc. Darwin began to shed this idea. Everything could have a single origin. ‘The origin of man is now proved,’ he wrote. ‘Our grandfather is Satan – in the form of a baboon!’

On top of this he read another book as revelatory to him as Lyell. Malthus’s Essay On the Principle of Population gave him ‘a theory by which to work’. Like human populations, lifeforms competed for the means of life – food, sex, territory. The principle of relations between species, as well as between rival populations, must be competition. ‘Nature’s forms’ did not demonstrate, as Christianity suggested, benevolence. There was struggle, and therefore suffering, everywhere. ‘Disease and pain in the world,’ he wrote, ‘and they talk of perfection?’ To meet changing situations in climate, habitat, availability of food, lifeforms adapted competitively. Those that flourished were ‘apter’ for the new environment. Hence variation. Hence divergence.

He had reached his key insight, one of the cornerstones (we now know) of biology: natural selection, the mechanism by which each species evolves.

He marvelled at its ‘grandeur’. A world filling with increasing myriads of different forms was much better than supposing (‘from a cramped imagination, surely’) that God created each species with tiny variations over and over again. Was it polite to God, to say he had kept making a series of ‘vile molluscous animals in infinite variation’? ‘How beneath the dignity of Him who said, Let there be light!

He knew these ideas would upset conventional aspects of religious faith. No one can be sure today that Darwin gave up all aspects of faith completely. He later said he lost belief gradually, and called the doctrine that people who do not believe will not be saved ‘damnable’. Doubting the Bible’s literal account of Creation and Flood was inevitable: the proof against them was written in stone. Doubting the historical truth of the Gospels he found harder. He had ‘dreamed’ of manuscripts being found that would prove the Gospels true. He was an empirical scientist; what he respected was evidence. Eventually he realised this particular proof would never come. When he married his cousin Emma Wedgwood, a loyal Christian, he explained to her his doubts about Christian revelation. He believed Christian morality but he was not convinced by the rest.

He knew this upset her, but she asked him not to change his ideas because of her. In 1851, when their ten-year-old daughter died (they had ten children of whom seven survived), he no longer went to church. But he never called himself atheist, only agnostic. In his sympathy for all life forms, what he found hardest to believe was that any force behind ‘nature’ was benevolent. He saw very clearly that new lifeforms evolved from the suffering and extinction of previous ones. What hurt him was the pain and waste of individuals involved in that process.

But in late 1838 he had not been touched personally by all this. Natural selection and its role in evolution was now the undisclosed hub of his thought. Undisclosed because he would have to prove it. If published simply as an idea, it would be set aside. He had to demonstrate it at work over many species. For the next twenty years he kept natural selection a secret and set out to prove it by experiment and also domestic breeding: artificial as a parallel to natural selection. He would write a ‘Big Book’, Natural Selection, but for now he wrote papers and books on geology, zoology and botany, bred fancy pigeons, orchids and bees, and dissected barnacles. Variety was the key. Varieties diverged to become new species. In 1841 he wrote a sketch of his argument called ‘Descent with Modification’; in 1844 another more detailed account. In spring 1856 he confessed his views to Lyell, who urged him to publish an essay to establish his priority to the idea, or he ‘would be forestalled’. In 1856 Darwin began writing – and was halfway through his book when, in June 1858, the bombshell fell.

Three months before, in the North Molucca Islands (now in Indonesia) a young man called Alfred Russel Wallace, an animal collector inspired by The Voyage of the Beagle, contracted malaria. Between shivery fits he pondered bird varieties on these islands, like Darwin in Galapagos. Suddenly he saw a mechanism by which evolution could work: natural selection, almost exactly as Darwin had seen it in 1838. He returned to his base on Ternate Island, wrote twenty pages, On the Tendency of Varieties to Depart Indefinitely from the Original Type, and sent them to the one man who would know if they were any good.

Darwin adored his children. He played with them as babies, involved them in madcap experiments, let them rampage over his study. Now he was watching his youngest child, an eighteen-month boy who probably had Down’s syndrome, die in pain of scarlet fever. Another child had diphtheria. Then he got Wallace’s letter. ‘Your words have come true with a vengeance,’ he wrote to Lyell. ‘I shd. now be glad to publish my ideas but cannot persuade myself I can do so honourably. I would far rather burn my whole book than that Wallace, or any man, shd. think I behaved in a paltry spirit. It seems hard to lose my priority of many years but I am not sure that affects the justice of the case.’

But, he said, he could hardly think. On 1 July, he followed his baby’s coffin to the village church. On the same day, with Wallace still in the Moluccas, Darwin’s colleagues read to the Linnaean Society a sketch of natural selection which Darwin had written earlier, along with Wallace’s Ternate letter, proving that both men had reached natural selection on their own and giving the world the first worked-out vision of evolution – with Wallace and Darwin as evolution’s joint discoverers.

Then Darwin began to write – not the Big Book but an ‘abstract’ of his ideas. That is the second book in this volume. When it was published in November 1859 it sold out in one go.

Public debate fastened instantly on human origins but you will not find a word about those here. (Darwin tackled them later, in The Descent of Man, 1871, when public opinion was ready to accept the idea that we evolved from apes). What the Origin does is show how natural selection is the mechanism by which species adapt and change. It does not lay divinity explicitly aside: it was Darwin’s younger follower T. H. Huxley who took that battle on. If anyone feels – as Darwin knew his wife did, their intimacy was intellectual as well as emotional and physical and he was deeply versed in theology himself – that divinity lies behind how the world worked, that is fine. Sophisticated theologians are not disturbed by the evolutionary principle of biology, neither by Darwin’s argument or evidence nor those of modern biology. (Darwin lived before the discovery of bacteria and genes but both provide further and more detailed proof of evolution.) What Darwin showed was the principle – and the processes – of organic change.

At the time, after the initial shock, most intelligent Christians accepted Darwin, knowing that there are other ways than literal ones of reading the Bible, or any other religious text. There was no incompatibility between evolution and faith until the 1920s and the rise of American fundamentalism: creationism and its 1980s mutation (in a nice demonstration of evolutionary adaptation) into intelligent design.

Immediately after the Origin, Samuel Butler complained that Darwin’s argument ‘banished mind from the universe’. But by 1860, only two years after the announcement of natural selection to the Linnaean Society, the future Archbishop of Canterbury preached a sermon accepting evolution. Evolution, he said, showed God working through ‘the slow working of natural causes’.

Yes, said the novelist Charles Kingsley, another devout Christian. God did not just make the world. ‘He did something more wonderful still; he made the world make itself’.

These two insights sum up the way a believer today, of any faith, can assimilate the empirical need to respect scientific proofs of evolution with the spiritual need, felt by millions of people including many scientists, for reverence and for belief in the divine.

Darwin took The Origin of Species through five more editions but what you have in your hands is his original version. It is the product of twenty years’ thought, honest questioning and experiment. It is also very deeply felt. Its author had just seen in the death of a third child the truth of his own argument that in the ‘slowly-changing language’ (p. 777) of the world’s physical history, only the individuals most apt for their environment survive. ‘Poor Baby died last night,’ he wrote to a friend. ‘I hope to God he did not suffer so much as he appeared.’

And if you read it for the writing, you realise that one of its most powerful features is its voice – that of a gentle, wide-ranging, honest and affectionate man driven by passionate sympathy for, and attentiveness to, all forms of life.

Ruth Padel, 2009


This edition reprints the text of the second edition of The Voyage of the Beagle and the first edition of The Origin of Species. The Historical Sketch and the Glossary, however, did not appear with the first edition but were added by Darwin later.



I HAVE STATED in the preface to the first Edition of this work, and in the Zoology of the Voyage of the Beagle, that it was in consequence of a wish expressed by Captain Fitz Roy, of having some scientific person on board, accompanied by an offer from him of giving up part of his own accommodations, that I volunteered my services, which received, through the kindness of the hydrographer, Captain Beaufort, the sanction of the Lords of the Admiralty. As I feel that the opportunities which I enjoyed of studying the Natural History of the different countries we visited, have been wholly due to Captain Fitz Roy, I hope I may here be permitted to repeat my expression of gratitude to him; and to add that, during the five years we were together, I received from him the most cordial friendship and steady assistance. Both to Captain Fitz Roy and to all the Officers of the Beagle1 I shall ever feel most thankful for the undeviating kindness with which I was treated during our long voyage.

This volume contains, in the form of a Journal, a history of our voyage, and a sketch of those observations in Natural History and Geology, which I think will possess some interest for the general reader. I have in this edition largely condensed and corrected some parts, and have added a little to others, in order to render the volume more fitted for popular reading; but I trust that naturalists will remember, that they must refer for details to the larger publications, which comprise the scientific results of the Expedition. The Zoology of the Voyage of the Beagle includes an account of the Fossil Mammalia, by Professor Owen; of the Living Mammalia, by Mr. Water-house; of the Birds, by Mr. Gould; of the Fish, by the Rev. L. Jenyns; and of the Reptiles, by Mr. Bell. I have appended to the descriptions of each species an account of its habits and range. These works, which I owe to the high talents and disinterested zeal of the above distinguished authors, could not have been undertaken, had it not been for the liberality of the Lords Commissioners of Her Majesty’s Treasury, who, through the representation of the Right Honourable the Chancellor of the Exchequer, have been pleased to grant a sum of one thousand pounds towards defraying part of the expenses of publication.

I have myself published separate volumes on the ‘Structure and Distribution of Coral Reefs;’ on the ‘Volcanic Islands visited during the Voyage of the Beagle;’ and on the ‘Geology of South America.’ The sixth volume of the ‘Geological Transactions’ contains two papers of mine on the Erratic Boulders and Volcanic Phenomena of South America. Messrs. Waterhouse, Walker, Newman, and White, have published several able papers on the Insects which were collected, and I trust that many others will hereafter follow. The plants from the southern parts of America will be given by Dr. J. Hooker, in his great work on the Botany of the Southern Hemisphere. The Flora of the Galapagos Archipelago is the subject of a separate memoir by him, in the ‘Linnean Transactions.’ The Reverend Professor Henslow has published a list of the plants collected by me at the Keeling Islands; and the Reverend J. M. Berkeley has described my cryptogamic plants.

I shall have the pleasure of acknowledging the great assistance which I have received from several other naturalists, in the course of this and my other works; but I must be here allowed to return my most sincere thanks to the Reverend Professor Henslow, who, when I was an under-graduate at Cambridge, was one chief means of giving me a taste for Natural History, – who, during my absence, took charge of the collections I sent home, and by his correspondence directed my endeavours, – and who, since my return, has constantly rendered me every assistance which the kindest friend could offer.

Down, Bromley, Kent.

June, 1845.

1 I must take this opportunity of returning my sincere thanks to Mr. Bynoe, the surgeon of the Beagle, for his very kind attention to me when I was ill at Valparaiso.


I TAKE THE opportunity of a new edition of my Journal to correct a few errors. At here