| → OMIT 1869 1872 |
| (generally of the more dominant forms of life), 1859 1860 1861 1866 |
|
| → in not only separating, but in apparently forming the 1869 1872 |
| which separate our 1859 1860 1861 1866 |
|
| → related species within the same areas; 1869 1872 |
| sub-genera, genera, and families; 1859 1860 1861 1866 |
|
| → linked together in 1869 1872 |
| in 1859 1860 1861 1866 |
|
| → OMIT 1869 1872 |
| linked together by affinity, 1859 1860 1861 |
| linked together, 1866 |
|
| → of the regions, or both; according to the nature of the 1866 1869 1872 |
| region; according to the nature of the 1859 1860 1861 |
|
| → the two or more 1869 1872 |
| different 1859 1860 1861 1866 |
|
| → as we do find, 1859 1860 1861 1866 1869 |
| OMIT 1872 |
|
| → in the several 1866 1869 |
| in the different 1859 1860 1861 |
| and this we do find in the several 1872 |
|
|
some one source; then
all the grand leading facts of geographical distribution are explicable on the theory of
→OMIT
together with subsequent modification and the multiplication of new forms. We can thus understand the high importance of barriers, whether of land or water,
→in not only separating, but in apparently forming the
several zoological and botanical provinces. We can thus understand the
of
→related species within the same areas;
and how it is that under different latitudes, for instance in South America, the inhabitants of the plains and mountains, of the forests, marshes, and deserts, are
→linked together in
so mysterious a
→OMIT
and are likewise linked to the extinct beings which formerly inhabited the same continent. Bearing in mind that the mutual
of organism to organism
of the highest importance, we can see why two areas having nearly the same physical conditions should often be inhabited by very different forms of life; for according to the length of time which has elapsed since
entered one
→of the regions, or both; according to the nature of the
communication which allowed certain forms and not others to enter, either in greater or lesser numbers; according or not, as those which entered happened to come
more or less direct competition with each other and with the
and according as the immigrants were capable of varying more or less rapidly, there would ensue in
→the two or more
regions, independently of their physical conditions, infinitely diversified conditions of life,— there would be an almost endless amount of organic action and reaction,— and we should
→as we do find,
some groups of beings greatly, and some only slightly
some
in great force, some existing in scanty numbers—
→in the several
great geographical provinces of the world.
|
