→ OMIT 1866 |
the Action of
1869 |
the Action of
1872 |
|
→
Extinction,
1866 |
Extinction,
1869 |
Extinction
,
1872 |
|
→ ought to have 1859 1860 1861 1866 |
has 1869 1872 |
|
→ we have seen 1859 1860 1861 1866 1869 |
as we saw 1872 |
|
→ of the species of 1859 1860 1861 1866 1869 |
species vary in 1872 |
|
→ 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 |
|
and feebly representing, as Mr. Waterhouse and others have remarked, our carnivorous, ruminant, and rodent mammals, could successfully compete with these
orders. In the Australian mammals, we see the process of diversification in an early and incomplete stage of development. |
→OMIT
→
Extinction,
|
After the foregoing discussion, which
→ought to have
been much
we
assume that the modified descendants of any one species will succeed
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
benefit being derived from divergence of character, combined with the principles of natural selection and of extinction,
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
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
→we have seen
in the second chapter,
on an average more
→of the species of
large genera
than
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
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
|