Search Results - The Complete Work of Charles Darwin Online

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

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 Changes of instinct and structure not necessarily simultaneous Difficulties of the theory of the Natural Selection of instincts Neuter or sterile insects Summary .. .. .. .. .. .. . .. .. 255-298 CHAPTER VIII. HYBRIDISM. Distinction between the sterility of first crosses and of

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

CHAPTER VII. INSTINCT. 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 Changes of instinct and structure not necessarily simultaneous Difficulties of the theory of the Natural Selection of instincts Neuter or sterile insects Summary. INSTINCTS might have been worked into the

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A1013.1 Book: Wallace, A. R. 1869. The Malay Archipelago: The land of the orang-utan, and the bird of paradise. A narrative of travel, with studies of man and nature. London: Macmillan and Co. vol. 1. Text

house, being particularly anxious about my insect treasures, I suspended the box from a bamboo on which I could detect no sign of ants, and then began skinning some of my birds. During my work I often glanced at my precious box to see that no intruders had arrived, till after a longer spell of work than usual I looked again, and saw to my horror that a column of small red ants were descending the string and entering the box. They were already busy at work at the bodies of my treasures, and

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

I will not pretend to conjecture. But as ants, which are not slave-makers, will, as I have seen, carry off pup of other species, if scattered near their nests, it is possible that such pup originally stored as food might become developed; and the foreign ants thus unintentionally reared would then follow their proper instincts, and do what work they could. If their presence proved useful T 2 [page] 27

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

a sort of honey, supplying the place of that excreted by the aphides, or the domestic cattle as they may be called, which our European ants guard and imprison. It will indeed be thought that I have an overweening confidence in the principle of natural selection, when I do not admit that such wonderful and well-established facts at once annihilate the theory. In the simpler case of neuter insects all of one caste, which, as I believe, have been rendered different from the fertile males and

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

the working ants of the several sizes differed wonderfully in shape, and in the form and number of the teeth. But the important fact for us is, that, though the workers can be grouped into castes of different sizes, yet they graduate insensibly into each other, as does the widely-different structure of their jaws. I speak confidently on this latter point, as Sir J. Lubbock made drawings for me, with the camera lucida, of the jaws which I dissected from the workers of the several sizes. Mr

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

each other and from their parents, has originated. We can see how useful their production may have been to a social community of ants, on the same principle that the division of labour is useful to civilised man. Ants, however, work by inherited instincts and by inherited organs or tools, whilst man works by acquired knowledge and manufactured instruments. But I must confess, that, with all my faith in natural selection, I should never have anticipated that this principle could have been

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

. , , acclimatisation of, 175. of Australia, 132. with thicker fur in cold climates, 167. , blind, in caves, 171. , extinct, of Australia, 414. Anomma, 294. Antarctic islands, ancient flora of, 479. Ants attending aphides, 259. , slave-making instinct, 271. , neuter, structure of, 290. Aphides, attended by ants, 259. Aphis, development of, 525. Apteryx, 217. Arab horses, 38. Aralo-Caspian Sea, 415. Archeopteryx, 375. Archiac, M. de, on the succession of species, 398. Artichoke, Jerusalem, 177. Ascension

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

, 532. Skulls of young mammals, 242, 519. Slave-making instinct, 271. Smith, Col. Hamilton, on striped horses, 200. , Mr. Fred., on slave-making ants, 272. , on neuter ants, 293. Snake with tooth for cutting through egg-shell, 269. STRATA. Somerville, Lord, on selection of sheep, 33. Sorbus, grafts of, 316. Spaniel, King Charles's breed, 37. Specialisation of organs, 144. Species, polymorphic, 51. , dominant, 64. , common, variable, 63. in large genera variable, 65. , groups of, suddenly

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A1013.1 Book: Wallace, A. R. 1869. The Malay Archipelago: The land of the orang-utan, and the bird of paradise. A narrative of travel, with studies of man and nature. London: Macmillan and Co. vol. 1. Text

the larger portion of them to be described by good entomologists. The Hymenoptera alone amounted to more than nine hundred species, among which were two hundred and eighty different kinds of ants, of which two hundred were new. The six years' delay in publishing my travels thus enables me to give, what I hope may be an interesting and instructive sketch of the main results yet arrived at by the study of my collections; and as the countries I have to describe are not much visited or written

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A1013.1 Book: Wallace, A. R. 1869. The Malay Archipelago: The land of the orang-utan, and the bird of paradise. A narrative of travel, with studies of man and nature. London: Macmillan and Co. vol. 1. Text

about five feet high round the rest of the body, which would soon be devoured by maggots, small lizards, and ants, leaving me the skeleton. There was a great gash in his face, which had cut deep into the bone, but the skull was a very fine one, and the teeth remarkably large and perfect. On June 18th I had another great success, and obtained a fine adult male. A Chinaman told me he had seen him feeding by the side of the path to the river, and I found [page] 7

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

the Malay archipelago. Thus also with ants, the several worker-castes are generally quite distinct; but in some cases, as we shall hereafter see, the castes are connected together by graduated varieties. It certainly at first appears a highly remarkable fact that the same female butterfly should have the power of producing at the same time three distinct female forms and a male; that a male Crustacean should generate two male forms and a female form, all widely different from each other; and

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

three years old with wonderfully little practice, had played a tune with no practice at all, he might truly be said to have done so instinctively. But it would be a serious error to suppose that the greater number of instincts have been acquired by habit in one generation, and then transmitted by inheritance to succeeding generations. It can be clearly shown that the most wonderful instincts with which we are acquainted namely, those of the hive-bee and of many ants, could not possibly have been

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

selection have probably acted together. Special Instincts. We shall, perhaps, best understand how instincts in a state of nature have become modified by selection, by considering a few cases. I will select only three, out of those which I shall have to discuss in my future work, namely, the instinct which leads the cuckoo to lay her eggs in other birds nests; the slave-making instinct of certain ants; and the cell-making power of the hive-bee: these two latter instincts have generally and justly been

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

being carried by them, as in the case of F. rufescens. Another day my attention was struck by about a score of the slave-makers haunting the same spot, and evidently not in search of food; they approached and were vigorously repulsed by an independent community of the slave-species (F. fusca); sometimes as many as three of these ants clinging to the legs of the slave-making F. sanguinea. The latter ruthlessly killed their small opponents, and carried their dead bodies as food to their nest, twenty

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

-communities: for these neuters often differ widely in instinct and in structure from both the males and fertile females, and yet, from being sterile, they cannot propagate their kind. The subject well deserves to be discussed at great length, but I will here take only a single case, that of working or sterile ants. How the workers have been U [page] 29

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

must pass over this preliminary difficulty. The great difficulty lies in the working ants differing widely from both the males and the fertile females in structure, as in the shape of the thorax, and in being destitute of wings and sometimes of eyes, and in instinct. As far as instinct alone is concerned, the wonderful difference in this respect between the workers and the perfect females, would have been better exemplified by the hive-bee. If a working ant or other neuter insect had been an

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

touched on the climax of the difficulty; namely, the fact that the neuters of several ants differ, not only from the fertile females and males, but from each other, sometimes to an almost incredible degree, and are thus divided into two or even three castes. The castes, moreover, do not generally graduate into each other, but are perfectly well defined; being as distinct from each other as are any two species of the same genus, or rather as any two genera of the same family. Thus in Eciton, there are

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

ants of this genus have well-developed ocelli. I may give one other case: so confidently did I expect to find gradations in important points of structure between the different castes of neuters in the same species, that I gladly availed myself of Mr. F. Smith's offer of numerous specimens from the same nest of the driver ant (Anomma) of West Africa. The reader will perhaps best appreciate the amount of difference in these workers, by my giving not the actual measurements, but a strictly accurate

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F387 Book: Darwin, C. R. 1869. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 5th ed. Tenth thousand. Text Image PDF

opposed to the theory of natural selection; and one of the most curious of these is the existence of two or three defined castes of workers or sterile female ants in the same community; but I have attempted to show how these difficulties can be mastered. With respect to the almost universal sterility of species when first crossed, which forms so remarkable a contrast with the almost universal fertility of varieties when crossed, I must refer the reader to the recapitulation of the facts given at