Comparison with 1869 |
|
CHAPTER IV. |
NATURAL
SELECTION; OR THE SURVIVAL OF THE FITTEST. SELECTION; OR THE SURVIVAL OF THE FITTEST. 1869 1872 |
SELECTION. 1859 1860 1861 1866 |
|
Natural Selection— its power compared with man's
selection— its power on characters of trifling importance— its power at all ages and on both sexes— Sexual Selection— On the generality of intercrosses between individuals of the same species— Circumstances favourable and unfavourable to
the results of Natural the results of Natural 1869 1872 |
Natural 1859 1860 1861 1866 |
Selection, namely, intercrossing, isolation, number of individuals— Slow action— Extinction caused by Natural Selection— Divergence of
Character Character 1866 1869 | Character, 1859 1860 1861 1872 |
related to the diversity of inhabitants of any small area, and to naturalisation— Action of Natural Selection, through Divergence of Character
and Extinction, on the descendants from a common parent— Explains the Grouping
of all organic
beings— Advance in organisation— Low forms preserved— Objections considered— Uniformity of certain characters due to their unimportance and to their not having been acted on by Natural Selection— Indefinite multiplication of species— Summary. beings— Advance in organisation— Low forms preserved— Objections considered— Uniformity of certain characters due to their unimportance and to their not having been acted on by Natural Selection— Indefinite multiplication of species— Summary. 1869 |
beings. 1859 1860 |
beings— Advance in organisation— Low forms preserved— Objections considered— Indefinite multiplication of species— Summary. 1861 |
beings — Advance in organisation— Low forms preserved— Objections considered— Indefinite multiplication of species— Summary. 1866 |
beings— Advance in organisation— Low forms preserved— Convergence of character— Indefinite multiplication of species— Summary. 1872 |
|
How How 1866 1869 | HOW 1859 1860 1861 1872 |
will the struggle for existence,
briefly discussed briefly discussed 1869 1872 |
discussed too briefly 1859 1860 1861 1866 |
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 in
nature? I think we shall see that it can act most effectually. Let
the the 1869 1872 |
it be borne in mind in what an 1859 1860 1861 1866 |
endless number of
peculiar variations in peculiar variations in 1869 |
strange peculiarities 1859 1860 1861 1866 |
slight variations and individual differences occurring in 1872 |
our domestic productions, and, in a lesser degree,
in those in those 1869 1872 | those 1859 1860 1861 1866 |
under nature,
be borne in mind; as well as the strength of be borne in mind; as well as the strength of 1869 1872 |
vary; and how strong 1859 1860 1861 1866 |
the hereditary
tendency. tendency. 1869 1872 | tendency 1859 1860 1861 1866 |
....... 1869 1872 | is. 1859 1860 1861 1866 |
Under domestication, it may be truly said that the whole organisation becomes in some degree plastic. 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 only 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. ↑1 blocks not present in 1859 1860 1861 1866 1869; present in 1872 | 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 also be 1861 1866 1869 1872 | be 1859 1860 |
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; life; 1861 1866 1869 1872 | life. 1859 1860 |
and consequently what infinitely varied diversities of structure may
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 sometimes
occur in the course of thousands of
generations? If such do occur, can we doubt
(remembering (remembering 1861 1866 1869 1872 | (remem- bering 1859 1860 |
|
CHAPTER IV. |
NATURAL
SELECTION. SELECTION. 1859 1860 1861 1866 |
SELECTION; OR THE SURVIVAL OF THE FITTEST. 1869 1872 |
|
Natural Selection— its power compared with
man's man's 1859 1861 1866 1869 1872 | mans 1860 |
selection— its power on characters of trifling importance— its power at all ages and on both sexes— Sexual Selection— On the generality of intercrosses between individuals of the same species— Circumstances favourable and unfavourable to
Natural Natural 1859 1860 1861 1866 |
the results of Natural 1869 1872 |
Selection, namely, intercrossing, isolation, number of individuals— Slow action— Extinction caused by Natural Selection— Divergence of
Character, Character, 1859 1860 1861 1872 | Character 1866 1869 |
related to the diversity of inhabitants of any small area, and to naturalisation— Action of Natural Selection, through Divergence of
Character Character 1859 1860 1861 1866 1869 | Character, 1872 |
and Extinction, on the descendants from a common parent— Explains the
Grouping Grouping 1859 1860 1861 1866 1869 | grouping 1872 |
of all organic
beings. beings. 1859 1860 |
beings— Advance in organisation— Low forms preserved— Objections considered— Indefinite multiplication of species— Summary. 1861 |
beings — Advance in organisation— Low forms preserved— Objections considered— Indefinite multiplication of species— Summary. 1866 |
beings— Advance in organisation— Low forms preserved— Objections considered— Uniformity of certain characters due to their unimportance and to their not having been acted on by Natural Selection— Indefinite multiplication of species— Summary. 1869 |
beings— Advance in organisation— Low forms preserved— Convergence of character— Indefinite multiplication of species— Summary. 1872 |
|
HOW HOW 1859 1860 1861 1872 | How 1866 1869 |
will the struggle for existence,
discussed too briefly discussed too briefly 1859 1860 1861 1866 |
briefly discussed 1869 1872 |
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
in in 1859 1860 1861 1866 1869 | under 1872 |
nature? I think we shall see that it can act most
effectually. effectually. 1859 1860 1861 1866 1869 | efficiently. 1872 |
Let
it be borne in mind in what an it be borne in mind in what an 1859 1860 1861 1866 |
the 1869 1872 |
endless number of
strange peculiarities strange peculiarities 1859 1860 1861 1866 |
peculiar variations in 1869 |
slight variations and individual differences occurring in 1872 |
our domestic productions, and, in a lesser degree,
those those 1859 1860 1861 1866 | in those 1869 1872 |
under nature,
vary; and how strong vary; and how strong 1859 1860 1861 1866 |
be borne in mind; as well as the strength of 1869 1872 |
the hereditary
tendency tendency 1859 1860 1861 1866 | tendency. 1869 1872 |
is. is. 1859 1860 1861 1866 | is. 1869 1872 |
Under domestication, it may be truly said that the whole organisation becomes in some degree plastic. ↑1 blocks not present in 1859 1860; present in 1861 1866 1869 1872 | 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 only 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
be be 1859 1860 | also be 1861 1866 1869 1872 |
borne in mind how infinitely complex and
close-fitting close-fitting 1859 1860 1861 1869 1872 | closefitting 1866 |
are the mutual relations of all organic beings to each other and to their physical conditions of
life. life. 1859 1860 | life; 1861 1866 1869 1872 |
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
sometimes sometimes 1859 1860 1861 1866 1869 | sometimes 1872 |
occur in the course of
thousands of thousands of 1859 1860 1861 1866 1869 | many successive 1872 |
generations? If such do occur, can we doubt
(remem- bering (remem- bering 1859 1860 | (remembering 1861 1866 1869 1872 |
|