Comparison with 1866 |
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CHAPTER III. |
STRUGGLE FOR EXISTENCE. |
Bears
on natural selection— The term used in a wide sense— Geometrical powers
of increase— Rapid increase of naturalised animals and plants— Nature of the checks to increase— Competition universal—
Effects
of climate— Protection from the number of individuals— Complex relations of all animals and plants throughout nature— Struggle for life most severe between individuals and varieties of the same species;
often severe between species of the same genus— The relation of organism to organism the most important of all relations. |
BEFORE entering on the subject of this chapter, I must make a few preliminary remarks, to show how the struggle for existence bears on Natural Selection. It has been seen in the last chapter that amongst organic beings in a state of nature there is some individual variability;
indeed I am not aware that this has ever been disputed. It is immaterial for us whether a multitude of doubtful forms be called species or sub-species or varieties; what rank, for instance, the two or three hundred doubtful forms of British plants are entitled to hold, if the existence of any well-marked varieties be admitted. But the mere existence of individual variability and of some few well-marked varieties, though necessary as the foundation for the work, helps us but little in understanding how species arise in nature. How have all those exquisite adaptations of one part of the organisation to another part, and to the conditions of life, and of one distinct
organic being to another being, been perfected? We see these beautiful co-adaptations most plainly in the woodpecker and
the mistletoe; the mistletoe; 1861 1866 1869 | missletoe; 1859 1860 | the misletoe; 1872 |
and only a little less plainly in the humblest parasite which clings to the hairs of a quadruped or feathers of a
bird; bird; 1859 1860 1861 1866 1869 | bird: 1872 |
in the structure of the beetle which dives through the
water; water; 1859 1860 1861 1866 1869 | water: 1872 |
in the plumed seed which is wafted by the gentlest breeze; in short, we see beautiful adaptations everywhere and in every part of the organic world. |
|
Again, it may be asked, how is it that varieties, which I have called incipient species, become ultimately converted into good and distinct species, which in most cases obviously differ from each other far more than do the varieties of the same species? How do those groups of species, which constitute what are called distinct
|
CHAPTER III. |
STRUGGLE FOR EXISTENCE. |
Its bearing Its bearing 1861 1866 1869 1872 | Bears 1859 1860 |
on natural selection— The term used in a wide sense— Geometrical
ratio ratio 1861 1866 1869 1872 | powers 1859 1860 |
of increase— Rapid increase of naturalised animals and plants— Nature of the checks to increase— Competition
universal— universal— 1859 1860 1861 1866 1872 | universal—Effects 1869 |
Effects Effects 1859 1860 1861 1866 1872 | Effects 1869 |
of climate— Protection from the number of individuals— Complex relations of all animals and plants throughout nature— Struggle for life most severe between individuals and varieties of the same
species: species: 1866 1869 1872 | species; 1859 1860 1861 |
often severe between species of the same genus— The relation of organism to organism the most important of all relations. |
BEFORE entering on the subject of this chapter, I must make a few preliminary remarks, to show how the struggle for existence bears on Natural Selection. It has been seen in the last chapter that amongst organic beings in a state of nature there is some individual
variability: variability: 1860 1861 1866 1869 1872 | variability; 1859 |
indeed I am not aware that this has ever been disputed. It is immaterial for us whether a multitude of doubtful forms be called species or sub-species or varieties; what rank, for instance, the two or three hundred doubtful forms of British plants are entitled to hold, if the existence of any well-marked varieties be admitted. But the mere existence of individual variability and of some few well-marked varieties, though necessary as the foundation for the work, helps us but little in understanding how species arise in nature. How have all those exquisite adaptations of one part of the organisation to another part, and to the conditions of life, and of one
....... 1861 1866 1869 1872 | distinct 1859 1860 |
organic being to another being, been perfected? We see these beautiful co-adaptations most plainly in the woodpecker and
the misletoe; the misletoe; 1872 | missletoe; 1859 1860 | the mistletoe; 1861 1866 1869 |
and only a little less plainly in the humblest parasite which clings to the hairs of a quadruped or feathers of a
bird: bird: 1872 | bird; 1859 1860 1861 1866 1869 |
in the structure of the beetle which dives through the
water: water: 1872 | water; 1859 1860 1861 1866 1869 |
in the plumed seed which is wafted by the gentlest breeze; in short, we see beautiful adaptations everywhere and in every part of the organic world. |
|
Again, it may be asked, how is it that varieties, which I have called incipient species, become ultimately converted into good and distinct species, which in most cases obviously differ from each other far more than do the varieties of the same species? How do those groups of species, which constitute what are called distinct
|