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A238
Book:
Wallace, A. R. 1895. Natural selection and tropical nature: Essays on descriptive and theoretical biology. London: Macmillan.
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sensation or consciousness, and the development of man from the lower animals. I shall first consider the latter difficulty as more immediately connected with the subject discussed in the volume. What Natural Selection can Not do In considering the question of the development of man by known natural laws, we must ever bear in mind the first principle of natural selection, no less than of the general theory of evolution, that all changes of form or structure, all increase in the size of an organ or in
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A238
Book:
Wallace, A. R. 1895. Natural selection and tropical nature: Essays on descriptive and theoretical biology. London: Macmillan.
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possesses an organ quite disproportionate to his actual requirements—an organ that seems prepared in advance, only to be fully utilised as he progresses in civilisation. A brain one-half larger than that of the gorilla would, according to the evidence before us, fully have sufficed for the limited mental development of the savage; and we must therefore admit that the large brain he actually possesses could never have been solely developed by any of those laws of evolution, whose essence is, that
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A238
Book:
Wallace, A. R. 1895. Natural selection and tropical nature: Essays on descriptive and theoretical biology. London: Macmillan.
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direction, and for a special purpose, just as man guides the development of many animal and vegetable forms. The laws of evolution alone would, perhaps, never have produced a grain so well adapted to man's use as wheat and maize; such fruits as the seedless banana and breadfruit; or such animals as the Guernsey milch cow, or the London dray-horse. Yet these so closely resemble the unaided productions of nature, that we may well imagine a being who had mastered the laws of development of organic
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A238
Book:
Wallace, A. R. 1895. Natural selection and tropical nature: Essays on descriptive and theoretical biology. London: Macmillan.
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over and over again. In the one, evolution has had a fair change; in the other, it has had countless difficulties thrown in its way. The equatorial regions are then, as regards their past and present life-history, a more ancient world than that represented by the temperate zones, a world in which the laws which have governed the progressive development of life have operated with comparatively [page] 31
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A238
Book:
Wallace, A. R. 1895. Natural selection and tropical nature: Essays on descriptive and theoretical biology. London: Macmillan.
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many short intermissions of rest are taken, the bird may be said to live in the air an element in which it performs every kind of evolution with the utmost ease, frequently rising perpendicularly, flying backward, pirouetting or dancing off, as it were, from place to place, or from one part of a tree to another, sometimes descending, at others ascending. It often mounts up above the towering trees, and then shoots off like a little meteor at a right angle. At other times it gently buzzes away
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A238
Book:
Wallace, A. R. 1895. Natural selection and tropical nature: Essays on descriptive and theoretical biology. London: Macmillan.
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conjunction with the laws of evolution and natural selection. Protective Colours The nature of the two first groups, protective and warning colour, has been so fully detailed and illustrated in my chapter on Mimicry and other Protective Resemblances among Animals, that very little need be added here except a few words of general explanation. Protective colours are exceedingly prevalent in nature, comprising those of all the white arctic animals, the sandy-coloured desert forms, and the green
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A238
Book:
Wallace, A. R. 1895. Natural selection and tropical nature: Essays on descriptive and theoretical biology. London: Macmillan.
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the existing apes to the orang, the chimpanzee, the gorilla, and even to the gibbons, in a variety of ways; and these relations and differences are so numerous and so diverse that, on the theory of evolution, the ancestral form which ultimately developed into man must have diverged from the common stock whence all these various forms and their extinct allies originated. But so far back as the Miocene deposits of Europe we find the remains of apes allied to these various forms, and especially to
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A238
Book:
Wallace, A. R. 1895. Natural selection and tropical nature: Essays on descriptive and theoretical biology. London: Macmillan.
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link is a reproach to the doctrine of evolution; yet with strange inconsistency they refuse to accept evidence which in the case of any extinct or living animal, other than man, would be at least provisionally held to be sufficient, but follow in the very footsteps of those who blindly refused even to examine into the evidence adduced by the earlier discoverers of the antiquity of man, and thus play into the hands of those who can adduce his recent origin and unchangeability as an argument
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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CHAPTER XV. THE ORIGIN OF SPECIES (1859). IT is very interesting to separate the two arguments which occur interwoven in the Origin the argument for evolution and the argument for natural selection. The paramount importance of Darwin's contributions to the evidences of organic evolution are often forgotten in the brilliant theory which he believed to supply the motive cause of descent with modification. Organic evolution had been held to be true by certain thinkers during many centuries; but
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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with which they deal are not inconsistent with, but rather support, and often strongly support, a belief in Organic Evolution. Hence we see that this, incomparably the greatest work which the biological sciences have seen, begins with an explanation and defence and definition of the sphere of natural selection then passes to consider difficulties which are partly those of natural selection, and partly of organic evolution while it finally treats of the evidences of the latter process and the
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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, if not the whole cause, it is a very important factor in that operation; and that it must play a great part in the sorting out of varieties into those which are transitory and those which are permanent. The seventh essay, The Coming of Age of 'The Origin of Species,' was written in 1880. His complete confidence in evolution, as shown in this essay, may be contrasted with his cautious statements about natural selection. He boldly affirms evolution to be the fundamental doctrine of the Origin of
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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they knew as species were yet descended from a common ancestry. Those were their propositions; those were the fundamental principles of the doctrine of evolution. Darwinism was not evolution, nor Spencerism, nor H ckelism, nor Weismannism, but all these were built on the fundamental doctrine which was evolution, which they maintained so many years, and which was that upon which their President had put the seal of his authority that evening. . . . . Huxley thus hailed the statements of the President
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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CONTENTS CHAPTER PAGE I. THE SECRET OF DARWIN'S GREATNESS 9 II. BOYHOOD EDINBURGH CAMBRIDGE (1817 31) 16 III. VOYAGE OF THE BEAGLE (1831 36) 21 IV. CAMBRIDGE LONDON WORK UPON THE COLLECTIONS MARRIAGE GEOLOGICAL WORK JOURNAL OF THE VOYAGE CORAL REEFS FIRST RECORDED THOUGHTS ON EVOLUTION (1837 42) 25 V. DOWN GEOLOGY OF THE VOYAGE WORK ON CIRRIPEDES (1842 54) 35 VI. THE GROWTH OF THE ORIGIN OF SPECIES (1837 58) 42 VII. GROWTH OF THE ORIGIN (continued) CORRESPONDENCE WITH FRIENDS 50 VIII. DARWIN
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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of evolution, however it may have been brought about. With regard to the second ground, it is quite clear that Huxley had a very high opinion of natural selection: he thought it incomparably the best suggestion upon the subject that had ever been made, and he firmly believed that it accounted for something that it may even have taken a dominant part in bringing about evolution. On the other hand, he never felt quite confident about the entire sufficiency of the evidence in its favour. It is
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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. . . the general doctrine of evolution, to one side of which it gives expression, obtains, in the phenomena of biology, a firm base of operations whence it may conduct its conquest of the whole realm of nature. And again, on page 332: The fundamental doctrine of the 'Origin of Species,' as of all forms of the theory of evolution applied to biology, is 'that the innumerable species, genera, and families of organic beings with which the world is peopled have all descended, each within its own
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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defined in the title. It would seem appropriate to use the term Darwinism, as Wallace uses it, to indicate the causes of evolution which were suggested by Darwin himself, excluding those supposed causes which had been previously brought forward by earlier writers, and especially by Lamarck. The causes of evolution proposed by Lamarck are seriously disputed, and it is possible that they may be ultimately abandoned. If so, the integrity of Darwinism, as interpreted by some controversialists, would
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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sterility of first crosses and of hybrids being considered as an objection to the doctrine of Descent with Modification. Chapter IX. treats of the Imperfection of the Geological Record as the explanation of the apparently insufficient evidence of evolution during past ages. Chapter X., on the Geological succession of Organic Beings, shows that, allowing for this Imperfection of Record, the facts brought to light by Geology support a belief in evolution and in some cases even in natural
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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the natural processes on which Darwin founds his deductions are no more doubted than those of growth and multiplication; and, whether the full potency attributed to them is admitted or not, no one doubts their vast and far-reaching significance. But of evolution he speaks far more strongly: To any one who studies the signs of the times, the emergence of the philosophy of Evolution, [ bound hand and foot and cast into utter darkness during the millennium of theological scholasticism ] in the
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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line of mathematical reasoning on which the limit had been fixed. Huxley was called on to second the vote of thanks, and his speech had evidently been considered with the greatest care. I quote the passages which bear on evolution and natural selection from the Times of August 9th, 1894, in which a verbatim report is furnished: . . . As one of those persons who for many years past had made a pretty free use of the comfortable word 'evolution,' let him remind them that 34 years ago a considerable
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A334
Book:
Poulton, Edward Bagnall. 1896. Charles Darwin and the theory of natural selection. London: Cassell & Co.
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southwards over the continent (of South America). On the theory of separate creation the existence of such representative species received no explanation, although it became perfectly intelligible on the theory that a single species may be modified into distinct, although nearly related, species in the course of its range over a wide geographical area. Here, too, the evidence is in favour of evolution simply, and does not point to any cause of evolution. He also implies that even at this time he
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