| → South 1859 1860 1861 |
| tropical and temperate South 1866 1869 1872 |
|
| → On the other hand, these 1859 1860 1861 1866 |
| This similarity 1869 1872 |
|
| → gives, 1859 1860 |
| gives 1861 |
| does give, strongly 1866 1869 1872 |
|
|
yet
follow nearly the same instincts; why the
of
→South
America, for instance,
with mud like our British species. On the view of instincts having been slowly acquired through natural
we need not marvel at some instincts being
not perfect and liable to mistakes, and at many instincts causing other animals to suffer. |
|
| If species be only well-marked and permanent varieties, we can at once see why their crossed offspring should follow the same complex laws in their degrees and kinds of resemblance to their parents,— in being absorbed into each other by successive crosses, and in other such points,— as do the crossed offspring of acknowledged varieties.
→On the other hand, these
would be
if species
been independently
and varieties
been produced
secondary laws. |
|
| If we admit that the geological record is imperfect
an extreme degree, then
the record
→gives,
support the theory of descent with modification. New species have come on the stage slowly and at successive intervals; and the amount of change, after equal intervals of time, is widely different in different groups. The extinction of species and of whole groups of species, which has played so conspicuous a part in the history of the organic world, almost inevitably follows
the principle of natural selection; for old forms
supplanted by new and improved forms. Neither single species nor groups of species
when the chain of ordinary generation
once
broken. The gradual diffusion of dominant
with the slow modification of their descendants, causes the forms of life, after long intervals of time, to appear as if they had changed simultaneously throughout the world. The fact of the fossil remains of each formation being in some degree intermediate in character between the
|
