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See page in:
1859
1860
1861
1866
1869
1872

Compare with:
1859
1860
1861
1866
1869

→ the Action of 1872
the Action of 1869
OMIT 1866
→ Extinction , 1872
Extinction, 1866
Extinction, 1869
→ has 1869 1872
ought to have 1859 1860 1861 1866
→ as we saw 1872
we have seen 1859 1860 1861 1866 1869
→ species vary in 1872
of the species of 1859 1860 1861 1866 1869
→ do the rare and restricted species. 1866 1869 1872
rare species with restricted ranges. 1859 1860 1861
→ branching and 1866 1869 1872
little fan of 1859 1860 1861
a greater number of individuals be capable of there supporting themselves. A set of animals, with their organisation but little diversified, could hardly compete with a set more perfectly diversified in structure. It may be doubted, for instance, whether the Australian marsupials, which are divided into groups differing but little from each other, and feebly representing, as Mr. Waterhouse and others have remarked, our carnivorous, ruminant, and rodent mammals, could successfully compete with these
well-pronounced
well-developed
orders. In the Australian mammals, we see the process of diversification in an early and incomplete stage of development.
The
The
Probable
Probable
Action
Results
Effects
of
of
→ the Action of
Natural
Natural
Selection,
Selection
Selection
through
through
Divergence
Divergence
of
of
Character
Character
and
and
→ Extinction ,
in
on
the
the
Descendants
Descendants
of
of
a
a
Common
Common
Ancestor.
Ancestor.
Ancestor.
After the foregoing discussion, which →has been much
amplified,
compressed,
we
may,
may
I think,
....
assume that the modified descendants of any one species will succeed
by
....
so much the better as they become more diversified in structure, and are thus enabled to encroach on places occupied by other beings. Now let us see how this principle of
great
....
benefit being derived from divergence of character, combined with the principles of natural selection and of extinction,
will
....
tend
tends
to act.
The accompanying diagram will aid us in understanding this rather perplexing subject. Let A to L represent the species of a genus large in its own country; these species are supposed to resemble each other in unequal
degress,
degrees,
as is so generally the case in nature, and as is represented in the diagram by the letters standing at unequal distances. I have said a large genus, because →as we saw in the second chapter,
that
....
on an average more →species vary in large genera
vary
....
than
of
in
small genera; and the varying species of the large genera present a greater number of varieties. We have, also, seen that the species, which are the commonest and the most
widely-diffused,
widely diffused,
vary more than →do the rare and restricted species. Let (A) be a common, widely-diffused, and varying species, belonging to a genus large in its own country. The →branching and diverging dotted lines of unequal lengths proceeding from (A), may represent its varying offspring. The variations are supposed to be extremely slight, but of the most diversified nature; they are
nor
not
supposed all to appear simultaneously, but often after long intervals of time; nor are they all supposed to endure for equal periods. Only those variations which are in some way profitable will be preserved or naturally selected. And here the importance of the principle of benefit
being
....
derived from divergence of character comes in; for this will generally lead to the most different or divergent variations