The Ascent of Man (28 page)

The common black vultures were abundant, but were rather put to it for food, being obliged to eat palm-fruits
in the forest when they could find nothing else.

I am convinced, from repeated observations, that the vultures depend entirely on sight, and not at all on smell, in seeking out their food.

The friends separated at Manaus, and Wallace set off up the Rio Negro. He was looking for places that had not been much explored by earlier naturalists; for if he was going to make a living by collecting,
he needed to find specimens of unknown or at least of rare species. The river was swollen with rain, so that Wallace and his Indians were able to take their canoe right into the forest. The trees hung low over the water. Wallace for once was awed by the gloom, but he was also elated by the variety in the forest, and he speculated how it might look from the air.

What we may fairly allow of tropical
vegetation is, that there is a much greater number of species, and a greater variety of forms, than in the temperate zones.

Perhaps no country in the world contains such an amount of vegetable matter on its surface as the valley of the Amazon. Its entire extent, with the exception of some very small portions, is covered with one dense and lofty primeval forest, the most extensive and unbroken
which exists upon the earth.

The whole glory of these forests could only be seen by sailing gently in a balloon over the undulating flowery surface above: such a treat is perhaps reserved for the traveller of a future age.

He was excited and frightened when for the first time he went into a native Indian village; but it is characteristic of Wallace that his lasting feeling was pleasure.

The
… most unexpected sensation of surprise and delight was my first meeting and living with a man in a state of nature – with absolute uncontaminated savages! … They were all going about their own work or pleasure which had nothing to do with white men or their ways; they walked with the free step of the independent forest-dweller, and … paid no attention whatever to us, mere strangers of an alien race.

In every detail they were original and self-sustaining, as are the wild animals of the forests, absolutely independent of civilisation, and who could and did live their lives in their own way, as they had done for countless generations before America was discovered.

It turned out that the Indians were not fierce but helpful. Wallace drew them into the business of collecting specimens.

During
the time I remained here (forty days), I procured at least forty species of butterflies quite new to me, besides a considerable collection of other orders.

One day I had brought me a curious little alligator of a rare species, with numerous ridges and conical tubercles,
Caiman gibbus
, which I skinned and stuffed, much to the amusement of the Indians, half a dozen of whom gazed intently at the
operation.

Sooner or later, amid the pleasures and the labours of the forest, the burning question began to flicker in Wallace’s acute mind. How had all this variety come about, so alike in design and yet so changeable in detail? Like Darwin, Wallace was struck by the differences between neighbouring species, and like Darwin he began to wonder how they had come to develop so differently.

There
is no part of natural history more interesting or instructive than the study of the geographical distribution of animals.

Places not more than fifty or a hundred miles apart often have species of insects and birds at the one, which are not found at the other. There must be some boundary which determines the range of each species; some external peculiarity to mark the line which each one does
not pass.

He was always attracted by problems in geography. Later, when he worked in the Malay archipelago, he showed that the animals on the western islands resemble species from Asia, and on the eastern islands from Australia: the line that divides them is still called the Wallace line.

Wallace was as acute an observer of men as of nature, and with the same interest in the origin of differences.
In an age in which Victorians called the people of the Amazon ‘savages’, he had a rare sympathy with their culture. He understood what language, what invention, what custom meant to them. He was perhaps the first person to seize the fact that the cultural distance between their civilisation and ours is much shorter than we think. After he conceived the principle of natural selection, that seemed
not only true but biologically obvious.

Natural selection could only have endowed savage man with a brain a few degrees superior to that of an ape, whereas he actually possesses one very little inferior to that of a philosopher. With our advent there had come
into existence a being in whom that subtle force we term ‘mind’ became of far more importance than mere bodily structure.

He was steadfast
in his regard for the Indians, and he wrote an idyllic account of their life when he stayed in the village of Javíta in 1851. At this point, Wallace’s journal breaks into poetry – well, into verse.

There is an Indian village; all around,

The dark, eternal, boundless forest spreads

Its varied foliage.

Here I dwelt awhile, the one white man

Among perhaps two hundred living souls.

Each day
some labour calls them. Now they go

To fell the forest’s pride, or in canoe

With hook, and spear, and arrow, to catch fish;

A palm-tree’s spreading leaves supply a thatch

Impervious to the winter’s storms and rain.

The women dig the mandiocca root,

And with much labour make of it their bread.

And all each morn and eve wash in the stream,

And sport like mermaids in the sparkling wave.

The children of small growth are naked, and

The boys and men wear but a narrow cloth.

How I delight to see those naked boys!

Their well-form’d limbs, their bright, smooth, red-brown skin,

And every motion full of grace and health;

And as they run, and race, and shout, and leap,

Or swim and dive beneath the rapid stream,

I pity English boys; their active limbs

Cramp’d and confined in tightly-fitting
clothes;

But how much more I pity English maids,

Their waist, and chest, and bosom all confined

By that vile torturing instrument called stays!

I’d be an Indian here, and live content

To fish, and hunt, and paddle my canoe,

And see my children grow, like young wild fawns,

In health of body and in peace of mind,

Rich without wealth, and happy without gold!

The sympathy is different from
the feelings that South American Indians aroused in Charles Darwin. When Darwin met the natives of Tierra del Fuego he was horrified: that is clear from his own words and from the drawings in his book on
The Voyage of the Beagle
. No doubt the ferocious climate had an influence on the customs of the Fuegians. But nineteenth-century photographs show that they did not look as beastly as they seemed
to Darwin. On his voyage home, Darwin had published a pamphlet with the captain of the
Beagle
at Cape Town to recommend the work that missionaries were doing to change the life of savages.

Wallace spent four years in the Amazon basin; then he packed his collections and started home.

The fever and ague now attacked me again, and I passed several days very uncomfortably. We had almost constant
rains; and to attend to my numerous birds and animals was a great annoyance, owing to the crowded state of the canoe, and the impossibility of properly cleaning them during the rain. Some died almost every day, and I often wished I had nothing whatever to do with them, though, having once taken them in hand, I determined to persevere.

Out of a hundred live animals which I had purchased or had
had given to me, there now only remained thirty-four.

The voyage home went badly from the start. Wallace was always an unlucky man.

On the 10th June we left [Manaus], commencing our voyage very unfortunately for me; for, on going on board, after bidding adieu to my friends, I missed my toucan, which had, no doubt, flown overboard, and not being noticed by any one, was drowned.

His choice of
a ship was most unlucky, since she was carrying an inflammable cargo of resin. Three weeks out, on 6 August 1852, the ship caught fire.

I went down into the cabin, now suffocatingly hot and full of smoke, to see what was worth saving. I got my watch and a small tin box containing some shirts and a couple of old note-books, with some drawings of
plants and animals, and scrambled up with them on
deck. Many clothes and a large portfolio of drawings and sketches remained in my berth; but I did not care to venture down again, and in fact felt a kind of apathy about saving anything, that I can now hardly account for.

The captain at length ordered all into the boats, and was himself the last to leave the vessel.

With what pleasure had I looked upon every rare and curious insect I had added
to my collection! How many times, when almost overcome by the ague, had I crawled into the forest and been rewarded by some unknown and beautiful species! How many places, which no European foot but my own had trodden, would have been recalled to my memory by the rare birds and insects they had furnished to my collection!

And now everything was gone, and I had not one specimen to illustrate the
unknown lands I had trod or to call back the recollection of the wild scenes I had beheld! But such regrets I knew were vain, and I tried to think as little as possible about what might have been and to occupy myself with the state of things which actually existed.

Alfred Wallace returned from the tropics, as Darwin had done, convinced that related species diverge from a common stock, and nonplussed
as to why they diverged. What Wallace did not know was that Darwin had hit on the explanation two years after he returned to England from his voyage in the
Beagle
. Darwin recounts that in 1838 he was reading the
Essay on Population
by the Reverend Thomas Malthus (‘for amusement’, says Darwin, meaning that it was not part of his serious reading) and he was struck by a thought in Malthus. Malthus
had said that population multiplies faster than food. If that is true of animals, then they must compete to survive: so that nature acts as a selective force, killing off the weak, and forming new species from the survivors who are fitted to their environment.

‘Here then I had at last got a theory by which to work,’ says Darwin. And you would think that a man who said that would set to work,
write papers, go out and lecture. Nothing of the kind. For four years Darwin did not even commit the theory to paper. Only in 1842 he wrote a draft of thirty-five pages, in pencil; and two years later expanded it to two hundred and thirty pages, in ink. And that draft he deposited with a sum of money and instructions to his wife to publish it if he died.

‘I have just finished my sketch of my
species theory,’ he wrote in a formal letter for her dated 5 July 1844 at Downe, and went on:

I therefore write this in case of my sudden death, as my most solemn and last request, which I am sure you will consider the same as if legally entered in my Will, that you will devote £400 to its publication, and further, will yourself, or through Hensleigh (Wedgwood), take trouble in promoting it.
I wish that my sketch be given to some competent person, with this sum to induce him to take trouble in its improvement and enlargement.

With respect to editors, Mr (Charles) Lyell would be the best if he would undertake it; I believe he would find the work pleasant, and he would learn some facts new to him.

Dr (Joseph Dalton) Hooker would be very good.

We feel that Darwin would really have
liked to die before he published the theory, provided after his death the priority should come to him. That is a strange character. It speaks for a man who knew that he was saying something deeply shocking to the public (certainly deeply shocking to his wife) and who was himself, to some extent, shocked by it. The hypochondria (yes, he had some infection from the tropics to excuse it), the bottles
of medicine, the enclosed, somewhat suffocating atmosphere of his house and study, the afternoon naps, the delay in writing, the refusal to argue in public: all those speak for a mind that did not want to face the public.

The younger Wallace, of course, was held back by none of these inhibitions. Brashly he went off in spite of all adversities to the Far East in 1854, and for the next eight years
travelled all over the Malay archipelago to collect specimens of the wild life there that he would sell in England. By now he was convinced that species are not immutable; he published an essay
On the Law which has regulated the Introduction of New Species
in 1855; and from then ‘the question of how changes of species could have been brought about was rarely out of my mind’.

In February of 1858
Wallace was ill on the small volcanic island of Ternate in the Moluccas, the Spice Islands, between New Guinea and Borneo. He had an intermittent fever, was hot and cold by turns, and thought fitfully. And there, on a night of fever, he recalled the same book by Malthus and had the same explanation flash on him that had struck Darwin earlier.

It occurred to me to ask the question, Why do some
die and some live? And the answer was clearly, that on the whole the best fitted lived. From the effects of disease the most healthy escaped; from enemies, the strongest, the swiftest, or the most cunning; from famine, the best hunters or those with the best digestion; and so on.

Then I at once saw, that the ever present variability of all living things would furnish the material from which,
by the mere weeding out of those less adapted to the actual conditions, the fittest alone would continue the race.

There suddenly flashed upon me the
idea
of the survival of the fittest.

The more I thought over it, the more I became convinced that I had at length found the long-sought-for law of nature that solved the problem of the
Origin of Species
… I waited anxiously for the termination
of my fit so that I might at once make notes for a paper on the subject. The same evening I did this pretty fully, and on the two succeeding evenings wrote it out carefully in order to send it to Darwin by the next post, which would leave in a day or two.