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F376
Book:
Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue.
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cold climates, 133. ——, blind, in caves, 137. ——, extinct, of Australia, 339. Anomma, 240. Antarctic islands, ancient flora of, 399. Antirrhinum, 161. Ants attending aphides, 210. ——, slave-making instinct, 219. ——, neuter, structure of, 236. Aphides, attended by ants, 210. Aphis, development of, 442. Apteryx, 182. Arab horses, 35. Aralo-Caspian Sea, 339. Archiac, M. de, on the succession of species, 325. Artichoke, Jerusalem, 142. Ascension, plants of, 389. Asclepias, pollen of, 193. Asparagus
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F376
Book:
Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue.
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, their 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. Silene, fertility of crosses, 257. Silliman, Prof., on blind rat, 137. Skulls of young mammals, 197, 436. 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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F380
Book:
Darwin, C. R. 1860. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. New York: D. Appleton. New edition, revised and augmented.
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perfect The law of Unity of Type and of the Conditions of Existence embraced by the theory of Natural Selection, 154 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 Difficulties on the theory of the Natural Selection of instincts Neuter or sterile insects Summary
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F380
Book:
Darwin, C. R. 1860. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. New York: D. Appleton. New edition, revised and augmented.
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away; but in about a quarter of an hour, shortly after all the little yellow ants had crawled away, they took heart and carried off the pup . One evening I visited another community of F. sanguinea, and found a number of these ants entering their nest, carrying the dead bodies of F. fusca (showing that it was not a migration) and numerous pup . I traced the returning file burthened with booty, for about forty yards, to a very thick clump of heath, whence I saw the last individual of F. sanguinea
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F380
Book:
Darwin, C. R. 1860. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. New York: D. Appleton. New edition, revised and augmented.
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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 pup originally stored as food might become developed; and the ants thus unintentionally reared would then follow their proper instincts, and do what work they could. If their presence proved useful to the species which had seized them if it were more advantageous to this species to capture workers than to procreate them the
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F380
Book:
Darwin, C. R. 1860. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. New York: D. Appleton. New edition, revised and augmented.
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they have an enormously developed abdomen which secretes 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 or 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 my theory. In the simpler case of neuter insects all of one caste or of the same kind, which
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F380
Book:
Darwin, C. R. 1860. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. New York: D. Appleton. New edition, revised and augmented.
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had been continually selected, which produced more and more of 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
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F380
Book:
Darwin, C. R. 1860. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. New York: D. Appleton. New edition, revised and augmented.
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insects, on the same principle that the division of labour is useful to civilised man. As ants work by inherited instincts and by inherited tools or weapons, and not by acquired knowledge and manufactured instruments, a perfect division of labour could be effected with them only by the workers being sterile; for had they been fertile, they would have intercrossed, and their instincts and structure would have become blended. And nature has, as I believe, effected this admirable division of labour in
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p 247 (a) heat on more than absolute heat, so that same day, so more sensitive in midday than during morning or evening — Less sensitive during Autumn.— Too great warmth makes them leaves torpid — The Activity seems to depend on the processes of life gong on vigorously rather than on the power of direct temperature.— p 247 (b) Drosera does not sleep.— p. 248 (a) living ants caused move the nascent tentacles to bend in 5' — the marginal ones began bending in 10' it was 1° before, they reached
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F380
Book:
Darwin, C. R. 1860. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. New York: D. Appleton. New edition, revised and augmented.
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ants. From the first growth of the tree, many a limb and branch has decayed and dropped off; and these lost branches of various sizes may represent those whole orders, families, and genera which have now no living representatives, and which are known to us only from having been found in a fossil state. As we here and there see a thin straggling branch springing from a fork low down in a tree, and which by some chance has been favoured and is still alive on its summit, so we occasionally see an
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F380
Book:
Darwin, C. R. 1860. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. New York: D. Appleton. New edition, revised and augmented.
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distinct Kitty-wrens, a habit wholly unlike that of any other known bird. Finally, it may not be a logical deduction, but to my imagination it is far more satisfactory to look at such instincts as the young cuckoo ejecting its foster brothers, ants making slaves, the larv of ichneumonid feeding within the live bodies of caterpillars, not as especially endowed or created instincts, but as small consequences of one general law, leading to the advancement of all organic beings, namely, multiply, vary
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F380
Book:
Darwin, C. R. 1860. The origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. New York: D. Appleton. New edition, revised and augmented.
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produced, 39. mountain, varieties of, 73. Shells, colours of, 121. littoral, seldom embedded, 253. fresh-water, dispersal of, 335. of Madeira, 341. land, distribution of, 346. Silene, fertility of crosses, 227. Silliman, Prof., on blind rat, 125. Skulls of young mammals, 176, 330. Slave-making instinct, 195. Smith, Col. Hamilton, on striped horses, 148. Mr. Fred., on slave-making ants, 195. Smith, Mr. Fred., on neuter ants, 212. Mr., of Jordan Hill, on the degradation of coast-rocks, 248. Snap
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F376
Book:
Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue.
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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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F376
Book:
Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue.
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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 cuckoos instinct is, that [page] 21
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F376
Book:
Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue.
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case of F. rufescens) their slaves in their 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
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F376
Book:
Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue.
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their fertile offspring a tendency to produce sterile members having the same modification. And I believe that this process has been repeated, until that prodigious amount 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
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F376
Book:
Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue.
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smaller workers had been the most useful to the community, and those males and females had been continually selected, which produced more and more of 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
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F376
Book:
Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue.
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workers, by my giving not the actual measurements, but a strictly accurate illustration: the difference was the same as if we were to see a set of workmen building 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
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F376
Book:
Darwin, C. R. 1860. On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. 2d ed., second issue.
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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 given at the end of the eighth chapter, which seem to me
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A14
Review:
Murray, Andrew. 1860. On Mr Darwin's theory of the origin of species. (Read 20 February) Proceedings of the Royal Society of Edinburgh 4: 274-291.
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to give as showing the alteration of structure in a type consequent upon different physical conditions of life. The Colaptes, although allied to the woodpeckers, differ from them in mode of life, inasmuch as they feed upon ants; and, in structure, inasmuch as not requiring that most essential part of the organisation of a woodpecker (its peculiar hammering bill and strong tail) they do not possess them, while they retain the peculiar tongue and accessory muscles still necessary for securing
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