| → selection. 1859 1861 1866 1869 1872 |
| selection. If we admire the several ingenious contrivances, by which the flowers of the orchis and of many other plants are fertilised through insect agency, can we consider as equally perfect the elaboration by our fir-trees of dense clouds of pollen, in order that a few granules may be wafted by a chance breeze on to the ovules? 1860 |
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| → the flowers of the 1859 1861 |
| OMIT 1866 1869 1872 |
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| → by our fir-trees 1859 1861 |
| OMIT 1866 1869 1872 |
|
| → in order 1859 1861 |
| by our fir-trees, so 1866 1869 1872 |
|
| →
of Chapter
.—
1859 1861 |
|
the Law of Unity of Type and of the Conditions of Existence embraced by the Theory of Natural Selection.
1866 |
|
the Law of Unity of Type and of the Conditions of Existence embraced by the Theory of Natural Selection. 1869 |
|
the Law of Unity of Type and of the Conditions of Existence embraced by the Theory of Natural Selection
. 1872 |
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| → We 1859 1861 1866 1869 1872 |
|
Summary of Chapter.
— We
1860 |
|
|
is for the good of the community; and maternal love or maternal hatred, though the latter fortunately is most rare, is all the same to the inexorable principle of natural
→selection. If we admire the several ingenious contrivances, by which
→the flowers of the
and
many other plants are fertilised through insect agency, can we consider as equally perfect the elaboration
→by our fir-trees
of dense clouds of
→in order
that a few granules may be wafted by
chance
on to the ovules? |
|
→
of Chapter
.—
|
|
→We
have in this chapter discussed some of the difficulties and objections which may be urged against
theory. Many of them are
but I think that in the discussion light has been thrown on several facts, which on the
of independent acts of creation are utterly obscure. We have seen that species at any one period are not indefinitely variable, and are not linked together by a multitude of intermediate
partly because the process of natural selection
always
very slow, and
at any one
on a
few forms; and partly because the very process of natural selection
implies the continual supplanting and extinction of
and intermediate
Closely allied species, now living on a continuous area, must often have been formed when the area was not continuous, and when the conditions of life did not insensibly graduate away from one part to another. When two varieties are formed in two districts of a continuous area, an intermediate variety will often be formed, fitted for an intermediate zone; but from reasons assigned, the intermediate variety will usually exist in lesser numbers than the two forms which it connects; consequently the two latter, during the course of further modification, from
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