The Foundations of the Origin of Species. Darwin Charles

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СКАЧАТЬ strangest habits become associated, do. tricks, going in certain spots &c. &c., even against will, is excited by external agencies, and looks not to the end, – a person playing a pianoforte. If such a habit were transmitted it would make a marvellous instinct. Let us consider some of the most difficult cases of instincts, whether they could be possibly acquired. I do not say probably, for that belongs to our 3rd Part96, I beg this may be remembered, nor do I mean to attempt to show exact method. I want only to show that whole theory ought not at once to be rejected on this score.

      Every instinct must, by my theory, have been acquired gradually by slight changes «illegible» of former instinct, each change being useful to its then species. Shamming death struck me at first as remarkable objection. I found none really sham death97, and that there is gradation; now no one doubts that those insects which do it either more or less, do it for some good, if then any species was led to do it more, and then «?» escaped &c. &c.

      Take migratory instincts, faculty distinct from instinct, animals have notion of time, – like savages. Ordinary finding way by memory, but how does savage find way across country, – as incomprehensible to us, as animal to them, – geological changes, – fishes in river, – case of sheep in Spain98. Architectural instincts, – a manufacturer’s employee in making single articles extraordinary skill, – often said seem to make it almost «illegible», child born with such a notion of playing99, – we can fancy tailoring acquired in same perfection, – mixture of reason, – water-ouzel, – taylor-bird, – gradation of simple nest to most complicated.

      Bees again, distinction of faculty, – how they make a hexagon, – Waterhouse’s theory100, – the impulse to use whatever faculty they possess, – the taylor-bird has the faculty of sewing with beak, instinct impels him to do it.

      Last case of parent feeding young with different food (take case of Galapagos birds, gradation from Hawfinch to Sylvia) selection and habit might lead old birds to vary taste «?» and form, leaving their instinct of feeding their young with same food101, – or I see no difficulty in parents being forced or induced to vary the food brought, and selection adapting the young ones to it, and thus by degree any amount of diversity might be arrived at. Although we can never hope to see the course revealed by which different instincts have been acquired, for we have only present animals (not well known) to judge of the course of gradation, yet once grant the principle of habits, whether congenital or acquired by experience, being inherited and I can see no limit to the [amount of variation] extraordinariness «?» of the habits thus acquired.

       Summing up this Division. If variation be admitted to occur occasionally in some wild animals, and how can we doubt it, when we see [all] thousands «of» organisms, for whatever use taken by man, do vary. If we admit such variations tend to be hereditary, and how can we doubt it when we «remember» resemblances of features and character, – disease and monstrosities inherited and endless races produced (1200 cabbages). If we admit selection is steadily at work, and who will doubt it, when he considers amount of food on an average fixed and reproductive powers act in geometrical ratio. If we admit that external conditions vary, as all geology proclaims, they have done and are now doing, – then, if no law of nature be opposed, there must occasionally be formed races, [slightly] differing from the parent races. So then any such law102, none is known, but in all works it is assumed, in «?» flat contradiction to all known facts, that the amount of possible variation is soon acquired. Are not all the most varied species, the oldest domesticated: who «would» think that horses or corn could be produced? Take dahlia and potato, who will pretend in 5000 years103 «that great changes might not be effected»: perfectly adapted to conditions and then again brought into varying conditions. Think what has been done in few last years, look at pigeons, and cattle. With the amount of food man can produce he may have arrived at limit of fatness or size, or thickness of wool «?», but these are the most trivial points, but even in these I conclude it is impossible to say we know the limit of variation. And therefore with the [adapting] selecting power of nature, infinitely wise compared to those of man, «I conclude» that it is impossible to say we know the limit of races, which would be true «to their» kind; if of different constitutions would probably be infertile one with another, and which might be adapted in the most singular and admirable manner, according to their wants, to external nature and to other surrounding organisms, – such races would be species. But is there any evidence «that» species «have» been thus produced, this is a question wholly independent of all previous points, and which on examination of the kingdom of nature «we» ought to answer one way or another.

       PART II 104

      §§ IV. & V. «On the evidence from Geology.»

      I may premise, that according to the view ordinarily received, the myriads of organisms peopling this world have been created by so many distinct acts of creation. As we know nothing of the «illegible» will of a Creator, – we can see no reason why there should exist any relation between the organisms thus created; or again, they might be created according to any scheme. But it would be marvellous if this scheme should be the same as would result from the descent of groups of organisms from [certain] the same parents, according to the circumstances, just attempted to be developed.

      With equal probability did old cosmogonists say fossils were created, as we now see them, with a false resemblance to living beings105; what would the Astronomer say to the doctrine that the planets moved «not» according to the law of gravitation, but from the Creator having willed each separate planet to move in its particular orbit? I believe such a proposition (if we remove all prejudices) would be as legitimate as to admit that certain groups of living and extinct organisms, in their distribution, in their structure and in their relations one to another and to external conditions, agreed with the theory and showed signs of common descent, and yet were created distinct. As long as it was thought impossible that organisms should vary, or should anyhow become adapted to other organisms in a complicated manner, and yet be separated from them by an impassable barrier of sterility106, it was justifiable, even with some appearance in favour of a common descent, to admit distinct creation according to the will of an Omniscient Creator; or, for it is the same thing, to say with Whewell that the beginnings of all things surpass the comprehension of man. In the former sections I have endeavoured to show that such variation or specification is not impossible, nay, in many points of view is absolutely probable. What then is the evidence in favour of it and what the evidence against it. With our imperfect knowledge of past ages [surely there will be some] it would be strange if the imperfection did not create some unfavourable evidence.

      Give sketch of the Past, – beginning with facts appearing hostile under present knowledge, – then proceed to geograph. distribution, – order of appearance, – affinities, – morphology &c., &c.

      Our theory requires a very gradual introduction of new forms107, and extermination of the old (to which we shall revert). The extermination of old may sometimes be rapid, but never the introduction. In the groups descended from common parent, our theory requires a perfect gradation not differing more than breed«s» of cattle, or potatoes, or cabbages in forms. I do not mean that a graduated series of animals must have existed, intermediate between horse, mouse, tapir108, elephant [or fowl and peacock], but that these must have had a common parent, and between horse and this «?» parent &c., &c., but the common parent may possibly have differed СКАЧАТЬ