Search Results - The Complete Work of Charles Darwin Online

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F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

selection, 31. ——, two sub-breeds unintentionally produced, 36. ——, mountain, varieties of, 76. Shells, colours of, 132. ——, littoral, seldom embedded, 288. ——, fresh-water, dispersal of, 385. —— of Madeira, 391. ——, land, distribution of, 397. STRIPES. Silene, fertility of crosses, 257. Silliman, Prof., on blind rat, 137. Skulls of young mammals, 197, 437. Slave-making instinct, 219. Smith, Col. Hamilton, on striped horses, 164. ——, Mr. Fred., on slave-making ants, 219. ——, on neuter ants, 239

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

plant, and prevented their attendance during several hours. After this interval, I felt sure that the aphides would want to excrete. I watched them for some time through a lens, but not one excreted; I then tickled and stroked them with a hair in the same manner, as well as I could, as the ants do with their antennæ; but not one excreted. Afterwards I allowed an ant to visit them, and it immediately seemed, by its eager way of running about, to be well aware what a rich flock it had discovered

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

materials for the nest: both, but chiefly the slaves, tend, and milk as it may be called, their aphides; and thus both collect food for the community. In England the masters alone usually leave the nest to collect building materials and food for themselves, their slaves and larvæ. So that the masters in this country receive much less service from their slaves than they do in Switzerland. By what steps the instinct of F. sanguinea originated I will not pretend to conjecture. But as ants, which are

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

selection, 31. ——, two sub-breeds unintentionally produced, 36. ——, mountain, varieties of, 76. Shells, colours of, 132. ——, littoral, seldom embedded, 288. ——, fresh-water, dispersal of, 385. —— of Madeira, 391. ——, land, distribution of, 397. STRIPES. Silene, fertility of crosses, 257. Silliman, Prof., on blind rat, 137. Skulls of young mammals, 197, 437. Slave-making instinct, 219. Smith, Col. Hamilton, on striped horses, 164. ——, Mr. Fred., on slave-making ants, 219. ——, on neuter ants, 239

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CUL-DAR185.109.22 Draft: [1859] Draft of Origin, fair copy folio 23, Chap VII Instinct. / Drawing: Birds and Butterfly: Childrens' drawings on verso Text Image

The Complete Work of Charles Darwin Online [23] 23 Chap. VII Instinct. Slave-making instinct.— We will now turn to the extraordinary slave-making instinct of certain Ants. The Formica (Polyerges) rufescens, as was first discovered by Pierre Huber, a better observer even than his celebrated father, is absolutely dependent on its slaves. Without their aid the species in a single year would certainly become extinct. The males and females do no work: and the workers or sterile females, though most

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F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

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 thus acquired. It will be universally admitted that instincts are as important as corporeal structure for the welfare of each species, under its present conditions of life. Under changed conditions of life, it

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F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

instinct of certain ants; and the comb-making power of the hive-bee: these two latter instincts have generally, and most justly, been ranked by naturalists as the most wonderful of all known instincts. It is now commonly admitted that the more immediate and final cause of the cuckoo's instinct is, that [page] 217 CHAP. VII. OF THE CUCKOO

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F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

jaws. 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-nine yards distant; but they were prevented from

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F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

of difference between the fertile and sterile females of the same species has been produced, which we see in many social insects. But we have not as yet 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

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F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

the smaller workers, until all the workers had come to be in this condition; we should then have had a species of ant with neuters very nearly in the same condition with those of Myrmica. For the workers of Myrmica have not even rudiments of ocelli, though the male and female 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

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F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

a house of whom many were five feet four inches high, and many sixteen feet high; but we must suppose that the larger workmen had heads four instead of three times as big as those of the smaller men, and jaws nearly five times as big. The jaws, moreover, of 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

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F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

special difficulty on 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 females in the same community of ants; but I have attempted to show how this difficulty 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

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

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 thus acquired. It will be universally admitted that instincts are as important as corporeal structure for the welfare of each species, under its present conditions of life. Under changed conditions of life, it

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

instinct of certain ants; and the comb-making power of the hive-bee: these two latter instincts have generally, and most justly, been ranked by naturalists as the most wonderful of all known instincts. It is now commonly admitted that the more immediate and final cause of the cuckoo's instinct is, that [page] 217 CHAP. VII. OF THE CUCKOO

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

jaws. 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-nine yards distant; but they were prevented from

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

of difference between the fertile and sterile females of the same species has been produced, which we see in many social insects. But we have not as yet 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

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

the smaller workers, until all the workers had come to be in this condition; we should then have had a species of ant with neuters very nearly in the same condition with those of Myrmica. For the workers of Myrmica have not even rudiments of ocelli, though the male and female 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

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

a house of whom many were five feet four inches high, and many sixteen feet high; but we must suppose that the larger workmen had heads four instead of three times as big as those of the smaller men, and jaws nearly five times as big. The jaws, moreover, of 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

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PC-Virginia-Francis-F373 Printed: 1859 On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. [Francis Darwin's copy] London Text Image PDF

special difficulty on 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 females in the same community of ants; but I have attempted to show how this difficulty 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

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F373 Book: Darwin, C. R. 1859. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 1st ed., 1st issue. Text Image PDF

. Horner, Mr., on the antiquity of Egyptians, 18. Horns, rudimentary, 454. Horse, fossil, in La Plata, 318. Horses destroyed by flies in La Plata, 72. ——, striped, 163. ——, proportions of, when young, 445. Horticulturists, selection applied by, 32. Huber on cells of bees, 230. ——, P., on reason blended with instinct, 208. ——, on habitual nature of instincts, 208. ——, on slave making ants, 219. ——, on Melipona domestica, 225. Humble-bees, cells of, 225. Hunter, J., on secondary sexual characters, 150