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OriginOfSpecies - 475 Rows
Column Type #Values Column Stats
id int(11) 475 Column Stats
subject varchar(80) 14 Column Stats
title varchar(250) 139 Column Stats
ordinal int(11) 30 Column Stats
description text 474 Column Stats

475 rows, page 27 of 119 (4/p)
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Export to Excel select * from OriginOfSpecies order by subject, title, ordinal limit 104, 4 (Page 27: Row)
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03 - Struggle for Existence 03-11 - The Relation of Organism to Organism the Most Important of All Relations 40 Hence we can see that when a plant or animal is placed in a new country amongst new competitors, the conditions of its life will generally be changed in an essential manner, although the climate may be exactly the same as in its former home.

If its average numbers are to increase in its new home, we should have to modify it in a different way to what we should have had to do in its native country; for we should have to give it some advantage over a different set of competitors or enemies.
03 - Struggle for Existence 03-12 - Summary 10 It is good thus to try in imagination to give to any one species an advantage over another.

Probably in no single instance should we know what to do.

This ought to convince us of our ignorance on the mutual relations of all organic beings; a conviction as necessary as it is difficult to acquire.
03 - Struggle for Existence 03-12 - Summary 20 All that we can do, is to keep steadily in mind that each organic being is striving to increase in a geometrical ratio; that each at some period of its life, during some season of the year, during each generation or at intervals, has to struggle for life and to suffer great destruction.

When we reflect on this struggle, we may console ourselves with the full belief, that the war of nature is not incessant, that no fear is felt, that death is generally prompt, and that the vigorous, the healthy, and the happy survive and multiply.
04 - Natural Selection 04-01 - Natural Selection 10 How will the struggle for existence, briefly discussed in the last chapter, act in regard to variation?

Can the principle of selection, which we have seen is so potent in the hands of man, apply under nature?

I think we shall see that it can act most efficiently.

Let the endless number of slight variations and individual differences occurring in our domestic productions, and, in a lesser degree, in those under nature, be borne in mind; as well as the strength of the hereditary tendency.

Under domestication, it may be truly said that the whole organisation becomes in some degree plastic.

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But the variability, which we almost universally meet with in our domestic productions, is not directly produced, as Hooker and Asa Gray have well remarked, by man; he can neither originate varieties, nor prevent their occurrence; he can preserve and accumulate such as do occur.

Unintentionally he exposes organic beings to new and changing conditions of life, and variability ensues; but similar changes of conditions might and do occur under nature.

Let it also be borne in mind how infinitely complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life; and consequently what infinitely varied diversities of structure might be of use to each being under changing conditions of life.

Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should occur in the course of many successive generations?

If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind?

On the other hand, we may feel sure that any variation in the least degree injurious would be rigidly destroyed.

This preservation of favourable individual differences and variations, and the destruction of those which are injurious, I have called Natural Selection.