Notes from a small island: Charles Darwin's voyage to the Galapagos

The image of the old man on the £10 note is misleading. When Charles Darwin boarded 'HMS Beagle' in 1836 and made his now celebrated journey to the Galapagos, he was just 22 years old and poised to produce a diary as gripping as his scientific discoveries. As Darwin's complete works are put online, Richard Dawkins explains why he matters more than ever. And we publish extracts from the journals that transformed the way the world thinks about its origins

Charles Darwin is surely one of the most admirable men that ever lived. The idea that he launched upon the world in 1859 is a prime candidate for the title of the greatest idea ever to occur to a human mind.

If we measure the power of a scientific theory as some sort of ratio of how much it explains divided by how much it needs to assume, the theory of natural selection surely stands alone. This is why it is so important to have his complete works available online, and free of charge.

Think of what it explains: your existence and mine; the existence, form, diversity and apparently designed complexity of all living things, not only on this planet but probably wherever in the universe organised complexity may be found.

The explanatory work that the theory does, then, is immense. This is the very large numerator of the ratio. But the theory itself - the denominator - could hardly be smaller or more simple; you can write it out in a phrase: "Nonrandom survival of randomly varying hereditary elements."

We can probably pare it down even further, to a single notion: heredity. Given that there exists a system of heredity, two things will follow immediately: there will be a population of entities; and, since no copying process is perfect, there will be mutation. Therefore there will be hereditary variation in the population. It then follows that successful hereditary types will tend to increase in number at the expense of unsuccessful hereditary types.

That is probably all that is needed for life to get going and, given enough time, to evolve living machinery whose complexity and diversity progresses without obvious limit. Consider where we would be without Darwin's idea. We'd presumably have some sort of science of biology. Students would take degrees in the subject, books would be written, Nobel prizes would be won.

We'd know in some detail how living organisms work; we'd know that a human body is a teeming army of cells, a thousand times more numerous than the people in the world; we'd know that every one of these cells is a mass-production molecule-factory packed with the membranous equivalent of miles of sophisticated conveyor belt.

We'd know a great deal about how our bodies work, and how the bodies of shrimps, elephants and redwood trees work. But we wouldn't have the foggiest idea why. We would read volumes about living things but would have not a clue about where they came from originally, nor why they work so efficiently and purposefully.

It would undoubtedly be the most baffling problem in biology - probably in the whole of science and the whole of philosophy. This was the problem that Darwin (along with the younger English naturalist Alfred Russel Wallace) solved. We are now as certain as one can ever be in science that their solution is the correct one.

The Darwin solution to the riddle of existence is so powerfully simple, so felicitous to the modern mind, that it is hard for us to understand why it had to wait until the mid-19th century before anyone thought of it. It is further surprising - and probably telling - that this great inspiration, which looks so elegant from the modern armchair, eluded centuries of philosophers, mathematicians and polymaths.

Plato and Aristotle never even got close, fooling about with "essences" and "ideal forms" (and their continental successors, awash with discourse and dialectics, seem scarcely to have grasped the Darwinian principle to this day); Leibnitz and Newton gave us calculus but not an inkling of the reason for our own existence; Hume would surely have recognised the idea as a great one if it had occurred to him, but it never did. Having eluded this galaxy of all-time talent, the answer finally came, almost simultaneously, to two English naturalists. Darwin and Wallace, they alone, thought of it. And it was Darwin who fully documented it in The Origin of Species.

Charles Darwin should be read because, give or take a few minor details, the evolutionary world view that he has given us, that world view which is so utterly different from anything that went before, is, according to all that we have learnt since his time, literally true and unlikely ever to be superseded. Evolution as a fact has the same status as the fact that the earth is round and not flat (though people can be found to call either "mere theories"). It is Darwin who conclusively showed to the world that evolution is true.

It is sometimes suggested that Darwin is one of a trio of 19th-century giants, along with Marx and Freud. But are Marx and Freud really in his league? If we are ever contacted by alien beings from anywhere else in the universe sufficiently advanced technologically to reach us, will we have anything to say to them, when they step from their celestial Beagle?

We shall surely share with them at least parts of mathematics and physics. They will have computed the same value of pi; they will have the geometrical theorem that we attribute to Pythagoras; they will revere their equivalents of Einstein and of Planck. But there is no reason to suppose that they will have a Marx or a Freud.

Why should these men's discoveries have any applicability outside the narrow confines of one species of animal on one planet in one galaxy? It is only the anthropologists on the alien expedition who will have any time for Marx and Freud (let alone Derrida and Foucault!). But if I am right about the universal significance of Darwinian natural selection, our aliens will revere the immortal memory of their Charles Darwin.

Richard Dawkins' latest book is 'The God Delusion' (Bantam Press, £20)

Extracts from Darwin's Beagle Diaries

Extracted from: Journal of Researches into the Natural History and Geology of the Countries Visited During the Voyage of HMS Beagle Round the World, Under the Command of Capt Fitz Roy, RA

By Charles Darwin, MA, FRS

After having been twice driven back by heavy south-western gales, Her Majesty's Ship Beagle, a ten-gun brig, under the command of Captain Fitz Roy, RN, sailed from Devonport on the 27th of December, 1831. The object of the expedition was to complete the survey of South America, notably Patagonia and Tierra del Fuego, started on an earlier expedition. Charles Darwin was the ship's gentleman naturalist.

Bahia Blanca to Buenos Ayres, September 8th, 1832

I hired a Gaucho to accompany me on my ride to Buenos Ayres, though with some difficulty, as the father of one man was afraid to let him go, and another, who seemed willing, was described to me as so fearful, that I was afraid to take him, for I was told that even if he saw an ostrich at a distance, he would mistake it for an Indian, and would fly like the wind away. The distance to Buenos Ayres is about four hundred miles, and nearly the whole way through an uninhabited country. We started early in the morning; ascending a few hundred feet from the basin of green turf on which Bahia Blanca stands, we entered on a wide desolate plain. It consists of a crumbling argillaceo-calcareous rock, which, from the dry nature of the climate, supports only scattered tufts of withered grass, without a single bush or tree to break the monotonous uniformity. The weather was fine, but the atmosphere remarkably hazy; I thought the appearance foreboded a gale, but the Gauchos said it was owing to the plain, at some great distance in the interior, being on fire. After a long gallop, having changed horses twice, we reached the Rio Sauce: it is a deep, rapid, little stream, not above twenty-five feet wide. The second posta on the road to Buenos Ayres stands on its banks; a little above there is a ford for horses, where the water does not reach to the horses' belly; but from that point, in its course to the sea, it is quite impassable, and hence makes a most useful barrier against the Indians...

As it was early in the afternoon when we arrived, we took fresh horses, and a soldier for a guide, and started for the Sierra de la Ventana. This mountain is visible from the anchorage at Bahia Blanca; and Capt. Fitz Roy calculates its height to be 3340 feet - an altitude very remarkable on this eastern side of the continent. I am not aware that any foreigner, previous to my visit, had ascended this mountain; and indeed very few of the soldiers at Bahia Blanca knew anything about it. Hence we heard of beds of coal, of gold and silver, of caves, and of forests, all of which inflamed my curiosity, only to disappoint it... When we reached the foot of the main ridge, we had much difficulty in finding any water, and we thought we should have been obliged to have passed the night without any. At last we discovered some by looking close to the mountain, for at the distance even of a few hundred yards, the streamlets were buried and entirely lost in the friable calcareous stone and loose detritus. I do not think Nature ever made a more solitary, desolate pile of rock; - it well deserves its name of Hurtado, or separated. The mountain is steep, extremely rugged, and broken, and so entirely destitute of trees, and even bushes, that we actually could not make a skewer to stretch out our meat over the fire of thistle-stalks...

The dew, which in the early part of the night wetted the saddle-cloths under which we slept, was in the morning frozen. The plain, though appearing horizontal, had insensibly sloped up to a height of between 800 and 900 feet above the sea. In the morning (9th of September) the guide told me to ascend the nearest ridge, which he thought would lead me to the four peaks that crown the summit. The climbing up such rough rocks was very fatiguing; the sides were so indented, that what was gained in one five minutes was often lost in the next. At last, when I reached the ridge, my disappointment was extreme in finding a precipitous valley as deep as the plain, which cut the chain transversely in two, and separated me from the four points. This valley is very narrow, but flat-bottomed, and it forms a fine horse-pass for the Indians, as it connects the plains on the northern and southern sides of the range. Having descended, and while crossing it, I saw two horses grazing: I immediately hid myself in the long grass, and began to reconnoitre; but as I could see no signs of Indians I proceeded cautiously on my second ascent. It was late in the day, and this part of the mountain, like the other, was steep and rugged. I was on the top of the second peak by two o'clock, but got there with extreme difficulty; every twenty yards I had the cramp in the upper part of both thighs, so that I was afraid I should not have been able to have got down again. It was also necessary to return by another road, as it was out of the question to pass over the saddle-back. I was therefore obliged to give up the two higher peaks. Their altitude was but little greater, and every purpose of geology had been answered...

I was, on the whole, disappointed with this ascent. Even the view was insignificant; - a plain like the sea, but without its beautiful colour and defined outline. The scene, however, was novel, and a little danger, like salt to meat, gave it a relish. That the danger was very little was certain, for my two companions made a good fire - a thing which is never done when it is suspected that Indians are near. I reached the place of our bivouac by sunset, and drinking much maté, and smoking several cigaritos, soon made up my bed. The wind was strong and cold, but I never slept more comfortably.

September 11th

Proceeded to the third posta in company with the lieutenant who commanded it... we met a large herd of cattle and horses, guarded by fifteen soldiers; but we were told many had been lost. It is very difficult to drive animals across the plains; for if in the night a puma, or even a fox, approaches, nothing can prevent the horses dispersing in every direction; and a storm will have the same effect. A short time since, an officer left Buenos Ayres with five hundred horses, and when he arrived at the army he had under twenty.

Soon afterwards we perceived by the cloud of dust, that a party of horsemen were coming towards us; when far distant my companions knew them to be Indians, by their long hair streaming behind their backs. The Indians generally have a fillet round their heads, but never any covering; and their black hair blowing across their swarthy faces, heightens to an uncommon degree the wildness of their appearance. They turned out to be a party of Bernantio's friendly tribe, going to a salina for salt. The Indians eat much salt, their children sucking it like sugar. This habit is very different from that of the Spanish Gauchos, who, leading the same kind of life, eat scarcely any: according to Mungo Park, it is people who live on vegetable food who have an unconquerable desire for salt. The Indians gave us good-humoured nods as they passed at full gallop, driving before them a troop of horses, and followed by a train of lanky dogs.

September 12th and 13th

I staid at this posta two days, waiting for a troop of soldiers, which General Rosas had the kindness to send to inform me, would shortly travel to Buenos Ayres; and he advised me to take the opportunity of the escort. In the morning we rode to some neighbouring hills to view the country, and to examine the geology. After dinner the soldiers divided themselves into two parties for a trial of skill with the bolas. Two spears were stuck in the ground thirty-five yards apart, but they were struck and entangled only once in four or five times. The balls can be thrown fifty or sixty yards, but with little certainty. This, however, does not apply to a man on horseback; when the speed of the horse is added to the force of the arm, they can be whirled with effect to the distance of eighty yards...

One day I went out hunting at Bahia Blanca, but the men there merely rode in a crescent, each being about a quarter of a mile apart from the other. A fine male ostrich being turned by the headmost riders, tried to escape on one side. The Gauchos pursued at a reckless pace, twisting their horses about with the most admirable command, and each man whirling the balls round his head. At length the foremost threw them, revolving through the air: in an instant the ostrich rolled over and over, its legs fairly lashed together by the thong. The plains abound with three kinds of partridge, two of which are as large as hen pheasants. Their destroyer, a small and pretty fox, was also singularly numerous; in the course of the day we could not have seen less than forty or fifty. They were generally near their earths, but the dogs killed one. When we returned to the posta, we found two of the party returned who had been hunting by themselves. They had killed a puma, and had found an ostrich's nest with twenty-seven eggs in it. Each of these is said to equal in weight eleven hens' eggs; so that we obtained from this one nest as much food as 297 hens' eggs would have given...

September 17th

We followed the course of the Rio Tapalguen, through a very fertile country, to the ninth posta. Tapalguen itself, or the town of Tapalguen, if it may be so called, consists of a perfectly level plain, studded over, as far as the eye can reach, with the toldos, or oven-shaped huts of the Indians. The families of the friendly Indians, who were fighting on the side of Rosas, resided here. We met and passed many young Indian women, riding by two or three together on the same horse: they, as well as many of the young men, were strikingly handsome - their fine ruddy complexions being the picture of health. Besides the toldos, there were three ranchos; one inhabited by the Commandant, and the two others by Spaniards with small shops.

We were here able to buy some biscuit. I had now been several days without tasting any thing besides meat: I did not at all dislike this new regimen; but I felt as if it would only have agreed with me with hard exercise. I have heard that patients in England, when desired to confine themselves exclusively to an animal diet, even with the hope of life before their eyes, have hardly been able to endure it. Yet the Gaucho, for months together, touches nothing but beef...

We saw in the shops many articles, such as horsecloths, belts, and garters, woven by the Indian women. The patterns were very pretty, and the colours brilliant; the workmanship of the garters was so good that an English merchant at Buenos Ayres maintained they must have been manufactured in England, till he found the tassels had been fastened by split sinew...

September 20th

We arrived by the middle of the day at Buenos Ayres. The outskirts of the city looked quite pretty, with the agave hedges, and groves of olive, peach, and willow trees, all just throwing out their fresh green leaves. I rode to the house of Mr. Lumb, an English merchant, to whose kindness and hospitality, during my stay in the country, I was greatly indebted.

The city of Buenos Ayres is large; and I should think one of the most regular in the world. Every street is at right angles to the one it crosses, and the parallel ones being equidistant, the houses are collected into solid squares of equal dimensions, which are called quadras... In the centre of the town is the Plaza, where the public offices, fortress, cathedral, &c., stand. Here also, the old viceroys, before the revolution, had their palaces. The general assemblage of buildings possesses considerable architectural beauty, although none individually can boast of any.

The great corral, where the animals are kept for slaughter to supply food to this beef-eating population, is one of the spectacles best worth seeing. The strength of the horse as compared to that of the bullock is quite astonishing: a man on horseback having thrown his lazo round the horns of a beast, can drag it any where he chooses. The animal ploughing up the ground with outstretched legs, in vain efforts to resist the force, generally dashes at full speed to one side; but the horse immediately turning to receive the shock, stands so firmly that the bullock is almost thrown down, and it is surprising that their necks are not broken. The struggle is not, however, one of fair strength; the horse's girth being matched against the bullock's extended neck... When the bullock has been dragged to the spot where it is to be slaughtered, the matador with great caution cuts the hamstrings. Then is given the death bellow; a noise more expressive of fierce agony than any I know: I have often distinguished it from a long distance, and have always known that the struggle was then drawing to a close. The whole sight is horrible and revolting: the ground is almost made of bones; and horses and riders are drenched with gore.

Del Fuego, December 17th, 1832

A little after noon we doubled Cape St. Diego, and entered the famous strait of Le Maire. We kept close to the Fuegian shore, but the outline of the rugged, inhospitable Staten-land was visible amidst the clouds. In the afternoon we anchored in the Bay of Good Success. While * * entering we were saluted in a manner becoming the inhabitants of this savage land. A group of Fuegians partly concealed by the entangled forest, were perched on a wild point overhanging the sea; and as we passed by, they sprang up and waving their tattered cloaks sent forth a loud, sonorous shout. The savages followed the ship, and just before dark we saw their fire, and again heard their wild cry. The harbour consists of a fine piece of water half surrounded by low rounded mountains of clay-slate, which are covered to the water's edge by one dense gloomy forest...

In the morning the Captain sent a party to communicate with the Fuegians. When we came within hail, one of the four natives who were present advanced to receive us, and began to shout most vehemently, wishing to direct us where to land. When we were on shore the party looked rather alarmed, but continued talking and making gestures with great rapidity. It was without exception the most curious and interesting spectacle I ever beheld: I could not have believed how wide was the difference between savage and civilized man: it is greater than between a wild and domesticated animal, inasmuch as in man there is a greater power of improvement. The chief spokesman was old, and appeared to be the head of the family; the three others were powerful young men, about six feet high. The women and children had been sent away. These Fuegians are a very different race from the stunted, miserable wretches farther westward; and they seem closely allied to the famous Patagonians of the Strait of Magellan. Their only garment consists of a mantle made of guanaco skin, with the wool outside; this they wear just thrown over their shoulders, leaving their persons as often exposed as covered. Their skin is of a dirty coppery red colour.

The old man had a fillet of white feathers tied round his head, which partly confined his black, coarse, and entangled hair. His face was crossed by two broad transverse bars; one, painted bright red, reached from ear to ear and included the upper lip; the other, white like chalk, extended above and parallel to the first, so that even his eyelids were thus coloured. The other two men were ornamented by streaks of black powder, made of charcoal. The party altogether closely resembled the devils which come on the stage in plays like Der Freischutz.

Their very attitudes were abject, and the expression of their countenances distrustful, surprised, and startled. After we had presented them with some scarlet cloth, which they immediately tied round their necks, they became good friends. This was shown by the old man patting our breasts, and making a chuckling kind of noise, as people do when feeding chickens. I walked with the old man, and this demonstration of friendship was repeated several times; it was concluded by three hard slaps, which were given me on the breast and back at the same time. He bared his bosom for me to return the compliment, which being done, he seemed highly pleased. The language of these people, according to our notions, scarcely deserves to be called articulate...

They are excellent mimics: as often as we coughed or yawned, or made any odd motion, they immediately imitated us. Some of our party began to squint and look awry; but one of the young Fuegians (whose whole face was painted black, excepting a white band across his eyes) succeeded in making far more hideous grimaces. They could repeat with perfect correctness each word in any sentence we addressed them, and they remembered such words for some time. Yet we Europeans all know how difficult it is to distinguish apart the sounds in a foreign language. Which of us, for instance, could follow an American Indian through a sentence of more than three words? All savages appear to possess, to an uncommon degree, this power of mimicry. I was told, almost in the same words, of the same ludicrous habit among the Caffres: the Australians, likewise, have long been notorious for being able to imitate and describe the gait of any man, so that he may be recognised. How can this faculty be explained? Is it a consequence of the more practised habits of perception and keener senses, common to all men in a savage state, as compared with those long civilized?

Galapagos Archipelago, September 15th, 1833

The remaining land-birds form a most singular group of finches, related to each other in the structure of their beaks, short tails, form of body, and plumage: there are thirteen species, which Mr. Gould has divided into four sub-groups. All these species are peculiar to this archipelago; and so is the whole group, with the exception of one species of the subgroup Cactornis, lately brought from Bow island, in the Low Archipelago. Of Cactornis, the two species may be often seen climbing about the flowers of the great cactus-trees; but all the other species of this group of finches, mingled together in flocks, feed on the dry and sterile ground of the lower districts. The males of all, or certainly of the greater number, are jet black; and the females (with perhaps one or two exceptions) are brown. The most curious fact is the perfect gradation in the size of the beaks in the different species of Geospiza, from one as large as that of a hawfinch to that of a chaffinch, and even to that of a warbler. The largest beak in the genus Geospiza is shown in Fig. 1, (left) and the smallest in Fig. 3; but instead of there being only one intermediate species, with a beak of the size shown in Fig. 2, there are no less than six species with insensibly graduated beaks. The beak of the sub-group Certhidea, is shown in Fig. 4. The beak of Cactornis is somewhat like that of a starling; and that of the fourth sub-group, Camarhynchus, is slightly parrot-shaped. Seeing this gradation and diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends.

Reprinted courtesy of English Heritage. You can read the entire works of Darwin online at www.darwin-online.org.uk